From news Thu Mar 15 18:23:43 2001 Path: ditka!news.mv.net!news.shore.net!not-for-mail Followup-To: poster Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry,rec.travel.air Approved: hrose-saa@ckdhr.com Subject: Administrivia: sci.aeronautics.airliners Backlog Coming Content-Type: text/plain; charset=US-ASCII From: Helen Rose Message-ID: Organization: Support DNS LOC! X-Newsreader: Gnus v5.6.44/XEmacs 20.4 - "Emerald" Date: 15 Mar 2001 20:33:50 -0500 NNTP-Posting-Host: 209.58.172.141 X-Trace: news.shore.net 984706437 209.58.172.141 (Thu, 15 Mar 2001 20:33:57 EST) I got in touch with Karl Swartz, and until his life gets a little less hectic, I'll be the interim moderator of sci.aeronautics.airliners A large backlog will be appearing in sci.aeronautics.airliners within the next couple of days. Some of it will be out of date. Please take that into consideration when responding to the posts. Thanks for your patience. --Helen lead moderator, misc.transport.air-industry interim moderator, sci.aeronautics.airliners From hrose-saa@ckdhr.com Fri Mar 16 05:56:17 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:17 From: Ali Hegazi Subject: Gurney Flaps Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: BT Internet Reply-To: ali@poboxes.com NNTP-Posting-Host: host62-7-62-147.btinternet.com I am currently conducting studies into the effectiveness of gurney flaps as high lift devices on swept wings in particular... I would greatly appreciate any information about this topic or on gurney flaps in general, that anyone might have... Ali Hegazi _________________ Imperial College London From hrose-saa@ckdhr.com Fri Mar 16 05:56:18 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:18 From: "Stephens Lyle E" Subject: Aircraft identity Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM I'm trying to identify two aircraft in a photo taken at Moline, IL in the 1930's. The registrations numbers are NC726K and NC727K. Both aircraft have 2 of almost everything: wings, engines, fins and rudders, stabs and elevators. Is there a historic registration database I can consult? From hrose-saa@ckdhr.com Fri Mar 16 05:56:19 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:19 From: Dafydd ab Hugh Subject: Aircraft design question Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: The Loop Internet -- www.loop.com Dear aerospace engineers; My wife is an aerospace engineering student at Cal Poly Pomona, and for her senior thesis, she is supposed to design a passenger window for a future single-stage-to-orbit (SSTO) vehicle. This vehicle would take some number of passengers from a vertical takeoff into orbit or a suborbital arc and back down to a horizontal landing on a commercial airport runway. Think of Reagan's 1980s proposal of an "Orient Express." But she's been unable to find any publications that discuss designing passenger windows on commercial jets, hypersonic aircraft, spacecraft, or anything else. There must be something out there; engineers build airplanes with passenger windows, so somebody knows how to design them! Specifically, she needs to learn how to size the window and how to analyze stress across the window and the surrounding structure, including the interfaces between the window and the window frame; material analysis for the window; and heat-transfer analysis on the window. Does anybody on this newsgroup know of a textbook that can teach this sort of analysis, or commercially available aviation-analysis software -- preferably not in the thousands of dollars -- that can perform it? Are they similar to cockpit canopies, or completely different beasts? If similar, is there any publication giving the formulas for analyzing canopies? Please help -- we're getting desperate! If you want to e-mail, please remove the NO and the SPAM from the e-mail address before sending. Thank you for any help you can give us. Dafydd ab Hugh From hrose-saa@ckdhr.com Fri Mar 16 05:56:20 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:20 From: "Jeff" Subject: Landing lights question Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news3.rdc1.on.home.com 978873806 24.43.106.205 (Sun, 07 Jan 2001 05:23:26 PST) X-Newsreader: Microsoft Outlook Express 5.00.2615.200 Organization: Excite@Home - The Leader in Broadband http://home.com/faster NNTP-Posting-Host: 24.43.106.205 I'm not sure if this newsgroup is active or open to public posting but I have a question. At what point to landing lights get turned on and why at that point? I saw airliners approaching Pearson airport the other evening here in Toronto and they had lights on quite some time prior to landing and I wondered why so early since they can't serve much purpose until they are right over the runway. Thanks in advance for any information on this. Jeff From hrose-saa@ckdhr.com Fri Mar 16 05:56:21 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:21 From: rfspecialist@home.com (Joe) Subject: Lightning Strike out of Dorval ? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news3.rdc1.on.home.com 977874767 24.43.208.37 (Tue, 26 Dec 2000 15:52:47 PST) X-Newsreader: Forte Agent 1.5/32.452 Organization: Excite@Home - The Leader in Broadband http://home.com/faster NNTP-Posting-Host: 24.43.208.37 Hi A week ago Sunday I was on an Air Canada Flight from Montrea to Paris Charles De Gaulle sitting in the upper deck of a 747 400. At about 5000ft we encountered a horrific blast and flash of light. It was like a concussion gernade had went off. It was followed by heavy turbulance. The Captain came on and just said "Fasten Your Seatbelts Please". At first I thought it was a bomb but then attributed it to a direct Lightning strike. About 5 minutes followed when the captain came back on and said what we encountered was not a Lightning Strike but a Static Discharge and all systems were OK. Should he not have turned back to be safe? What is the procedure for this? You cannot tell from the cockpit if structural damage occured. Can anyone elaborate on this?It scared the dickens out of me.I heard one of the stewardesses say. " I heve never experienced anything like this in 32 years of flying" Spooked Frequent Flyer From hrose-saa@ckdhr.com Fri Mar 16 05:56:22 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:22 From: David Pinella Subject: Deice Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Structural Dynamics Research Corp. NNTP-Posting-Host: pcp1035.sdrc.com I was on a Canadair RJ yesterday. I think this is the first time that I have been on a plane that was deiced. I have a question. How much does deicing cost for a plane like this? A 747? How many gallons? Is it recycled? It looked like they used a pink spray and then a green spray. I assume the red is a deice and the green is an anti ice, like ethelyne glycol. It stuck really nice to the wing, very pretty. What was the red? Thanks! Dave P From hrose-saa@ckdhr.com Fri Mar 16 05:56:23 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:23 From: Merlin Dorfman Subject: 727 with winglets?? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: TIN [version 1.2 PL2] Organization: a2i network NNTP-Posting-Host: waltz.rahul.net While stuck in traffic this week, I'm sure I saw a 727 with winglets on approach to San Jose airport. I was right under the plane and so could not see any markings. Is there such an aircraft? If so, who operates it? (Cargo only?) Thanks, Merlin Dorfman DORFMAN@COMPUTER.ORG From hrose-saa@ckdhr.com Fri Mar 16 05:56:24 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:24 From: "Ben-Yosef" Subject: help! for seaplane in the "sea of Galilee" in the1930's. Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news.netvision.net.il 968327712 602 212.116.178.213 (7 Sep 2000 11:55:12 GMT) X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: NetVision Israel NNTP-Posting-Host: 212.116.178.213.knet.co.il I'm looking for information about the " Imperial Airways" seaplane landing in the "sea of Galilee" ,(as a stop in a regular route between England and India in the 1930's ?) who knows??? From hrose-saa@ckdhr.com Fri Mar 16 05:56:25 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:25 From: Pete Mellor Subject: Concorde tyres Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Dear all, There have been a number of different reports about how (and/or "if") tyre failure contributed to the recent crash of Concorde. A few queries to the list:- 1. How come *any* aircaft tyre fails catastrophically? Surely fuse plugs should ensure that a tyre fails in a controlled and predictable fashion if overstressed? 2. One newspaper reported that experts from the Goodyear Co. had flown in from the US to assist the investigation. Presumably this is because Goodyear supplied the tyres for Concorde? 3. A friend of mine claims to have heard a report on a news bulletin (which I did not hear myself, and have been unable to confirm from press reports) that the French and British fleets use different tyres, hence the willingness of BA to continue flights while Air france keeps its fleet grounded. Does anyone know anything about this? 4. As a variant on 3 above, a more recent report had it that the French fleet had retained some sort of "cover" on the bogies that had been removed from the British fleet in a modification following an early incident in which it contributed to the rupture of a fuel tank or line after a tyre blow-out. Again, does anyone know anything? Cheers! Pete Mellor ---------------------------------------------------------------------- From hrose-saa@ckdhr.com Fri Mar 16 05:56:26 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 16 Mar 2001 05:56:26 From: "news free brut" Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: nnrp4.proxad.net 964907695 213.228.11.58 (Sat, 29 Jul 2000 23:54:55 CEST) Organization: Guest of ProXad - France X-Newsreader: Microsoft Outlook Express 4.72.3110.5 NNTP-Posting-Host: 213.228.11.58 Latest news are that the second engine failure and the fire would have been brung about by the tyres. Blowing out, it damaged the wing and the engine. The fire extended to the other engine on the same wing, reducing too much the thrust to gain altitude. There doesn't seem to have any link with the repairs of the thrust reverser . They don't know yet the reasons why some tyres bursted. Excuse my english writing, Brut. Helen Rose a écrit dans le message ... >An Air France Concorde (unknown registration number) crashed after >departing Paris CDG en route to New York Kennedy. AF4590 was on a >charter flight, and it was full with 100 passengers (who were on a with >a tour group from Germany), 9 crew (3 cockpit, 6 cabin). All aboard >perished, as did four on the ground. A dozen more on the ground were >injured. > >The usual eyewitness reports have surfaced about the plane being alight >before crashing (which appear to be correct, at least from the photos >that I have viewed). Other reports said the plane had trouble gaining >altitude. > >More information is available on http://www.cnn.com/ (including some >horrifying photographs) and http://www.itn.co.uk/ > >If anybody has more information to contribute, including good sources of >news, please do so. > >--Helen From hrose-saa@ckdhr.com Fri Mar 16 05:56:27 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:27 From: "Marco" Subject: Fokker 70/100 Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news.infostrada.it 964809641 151.25.241.54 (Fri, 28 Jul 2000 20:40:41 MET DST) Organization: [Infostrada] X-Newsreader: Microsoft Outlook Express 5.00.2919.6600 NNTP-Posting-Host: 151.25.241.54 Hello I am a FANATIC of the Fokker 70 / 100 , but I couldn't find any datas about the airfoil section (Shorts) and the jet nacelles (Grumman). Is there anyone who knows where I can find those informations (or is it industrial secret) ? Thanks a lot. Marco "bluerider" Sap (from Turin, Italy) From hrose-saa@ckdhr.com Fri Mar 16 05:56:28 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 16 Mar 2001 05:56:28 From: ebarber Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news.fsu.edu 964797963 3410 146.201.26.201 (28 Jul 2000 15:26:03 GMT) Organization: Florida State University NNTP-Posting-Host: dingo.eng.fsu.edu On 25 Jul 2000, Helen Rose wrote: > Helen Rose writes: > > > An Air France Concorde (unknown registration number) crashed after > > departing Paris CDG en route to New York Kennedy. > > F-BTSC, serial number 3 (unclear whether that's LN or MSN), which was > delivered in 1979. It had 3978 cycles and 11989 hours. > > The last C check was performed April 28, 2000. > > This plane was not found to have the microscopic cracks found on other > AF Concordes and BA Concordes. > > --Helen Some of the reports I saw said that the cracks being found in the Concorde wings were 2.0 inches in length. And that one day prior to the crash another Concorde was ground because the crack had grew to 2.6 inches. I personally believe the Concorde's days are soon to be numbered. Authorities are still deeming the planes to be safe (even with cracks) and operation, even into the year 2007. But please tell me how safe can a vehicle be if you are constantly using 25 year old parts off of planes which are NOT operational, to keep the rest of your fleet in the air. And though not as technical as many sites, USATODAY.com usually provides a good quick reference of facts on events such as this. --Ebarber P.S. Where is the HSCT when you need it? From hrose-saa@ckdhr.com Fri Mar 16 05:56:29 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 16 Mar 2001 05:56:29 From: Wolfgang Keller Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: [Posted via] Interactive Networx NNTP-Posting-Host: ip83.frankfurt61.pub-ip.de.psi.net BTW: Great to see this newsgroup working again. Congratulations to the moderator. :-) On Tue, 25 Jul 2000 21:57:48 +0200, Helen Rose wrote (in message ): > The usual eyewitness reports have surfaced about the plane being alight > before crashing (which appear to be correct, at least from the photos > that I have viewed). According to some recent eyewhitness reports, the engines were already on fire while the aircraft was still on the runway, but it was already beyond the 'point of no return'. It seems that in this case, however, the 'default' option to take off with was the less good choice. But obviously the pilot had no chance to know that. :-( Question to the more competent people here: How 'flyable' would a Concorde with two failed engines (on one side) be. I thought I've read somewhere that during the original trials, the manufacturers had to make the experience that the loss of one engine already made the aircraft yaw quite lot. So with both engines on one side lost, I guess there might have been problems with the other two no longer getting enough air in the intakes? And another question: Is there any case in which the 'pilot manuals' (or whatever they are called) recommend to abort the takeoff even beyond the 'point of no return'? -- Wolfgang Keller Zu Risiken und Nebenwirkungen von Junkmail lesen Sie de.admin.net-abuse.mail und fragen sie Ihren Postmaster oder Provider From hrose-saa@ckdhr.com Fri Mar 16 05:56:30 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:30 From: Andrew Sapuntzakis Subject: Antonov at ORD? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: schbbs.mot.com 964627660 25777 145.1.152.179 (26 Jul 2000 16:07:40 GMT) Organization: Motorola Control Centers NNTP-Posting-Host: cc781.comm.mot.com Driving by the "military" portion of O'Hare ~5pm on Jul 25, I saw a large 4-engine, top-wing transport. The body was all-white and the tail had blue-and-white "Antonov Design Bureau" livery. Any ideas which model this was (225?) and why it's there? -- CU Andrew S. andrewsa@comm.mot.com From hrose-saa@ckdhr.com Fri Mar 16 05:56:31 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:31 From: pro-entropy!darsys@cbbs.cts.com (Eric A. Seiden) Subject: Concorde Goes Down, Takes my spirits with it Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Pro-Entropy +1-305-994-3578 (DAR Systems Int'l -- Miami, FL) Hello : And now a brief interlude for a serious post. Today a Concorde crashed. Some of you are thinking "That's sad, but it was just another airplane." You can stop reading now. This isn't for you. Concorde, first came out in the late 1960s and entered commercial service in 1969. In March of this year it celebrated 30 years of accident-free service. That safety mark will likely remain untouched by any aircraft. I've seen the news reports on many plane crashes over the years, I've even survived one (Eastern Air Lines little fiasco at Washington National Airport 8/20/88). I'm always saddened when a plane goes down -- loss of life, loss of friends, family. But this one touched me a bit more than usual. I'm lucky, I've actually flown on Concorde, and it remains perhaps one of the most memorable experiences in my life. To fly on Concorde is to literally leave earth and fly so high you are in the deep, dark purple of the outer reaches of the atmosphere. There are no clouds, no bumps, an impossibly smooth ride. Out the window you see the curvature of the earth whilst sitting in the lap of luxury 60,000 feet above the planet. Concorde is unique is many ways: it actually lengthens as it flies from the friction of its speed, it has fuel that is moved to different compartments in its hull to change the balance of the aircraft. On Concorde I was with a slew of celebrities (whom I politely ignored), which made it seem even more elegant than it was, if possible. But Concorde is not only a means of absurdly fast transportation, it's a majestic, beautiful creature. Concorde used to visit Miami every day and it passed over my head every evening whilst sitting in traffic near the airport. Every time I saw it, I was in awe and always hoped to one day fly the magical metal bird. One day that wish came true. I have many souvenirs from that trip. One of the ones is a picture of my inside the terminal at CDG with Concorde in the background. It very well could be the same one that went down today. Concorde will still fly, perhaps three to five more years as they hope. But the amazing stress on the metal will ground Concorde much sooner, I'd imagine. It's too bad. With no company actively developing a modern SST, it's likely supersonic travel will cease to exist for the rest of our lives. If you are of a mind to, I might encourage you to save up for a trip on Concorde. The fleet will be grounded for some time, but it will take again to the air. There are great deals to be had -- probably even better to come as they encourage people to return -- including buy one, get one free. Yeah, it's a lot of money, but it's worth it. The sheer joy of being cruising at Mach2 is not to be believed. The view of earth from a perspective only an astronaut or a Concorde passenger can see is not to be believed. If I win the lotto, I'd take Concorde again. This piece has no point whatsoever. Maybe it's a eulogy to a way of travel that's no longer here. Maybe one of you will decide to try Concorde. It's a work of modern man that is beyond belief. As I type this, I stopped several times to look at the momentos of my Concorde trip. It makes me sad. But save your condolences for those who died. I'll end with this..... "... with silent lifting mind I've trod the high untrespassed sanctity of space, put out my hand and touched the face of God." John Gillespie McGee Jr -- E ============================================================================== "I'm going to do what every San Franciscan does who goes to Heaven. I'll look around and say, 'It's not bad, but it ain't San Francisco.'" -- Herb Caen Administrator NHL Panthers and Panthers Affiliates/Prospects mailing lists. "Imagine there's no heaven; it's easy if you try." -- John Lennon Pro-Entropy BBS 305-994-3578 (56K/v90) http://www.darsys.com From hrose-saa@ckdhr.com Fri Mar 16 05:56:32 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 16 Mar 2001 05:56:32 From: johnmcgrew@aol.com (JohnMcGrew) Subject: The Beginning of the End for the Concorde? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: AOL http://www.aol.com X-Newsreader: Session Scheduler First the fleet-wide discovery of wing cracks, and then today's Paris crash. A few months ago, 2-inch cracks were found in the rear-most wings of the entire BA seven-plane fleet. At that point, untrasonic testing was conducted, the cracks determined not to be structural, and the fleet was allowed to remain in service. The French were advised. But perhaps it was worse than identified. Last week, the crack on one plane had grown to 2.6 inches, forcing the grounding of the plane. As for the rest of the BA fleet, it was determined that passengers were never at risk, and that the six aircraft still in use remain completely safe, despite the cracks. In today's crash, at this point it appears as though there was some sort of failure resulting in both loss of power and control. Could it be long before the entire fleet is grounded, perhaps for good? John From hrose-saa@ckdhr.com Sat Mar 17 08:33:29 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:29 From: James Robinson Subject: Re: Fokker 70/100 References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Disorganized Marco wrote: > > I am a FANATIC of the Fokker 70 / 100 , but I couldn't find any datas about > the airfoil section (Shorts) and the jet nacelles (Grumman). Some basic aerodynamic comparison data is on this site: http://aerodyn.org/ Here is a list of airfoil sections used on various aircraft: http://amber.aae.uiuc.edu/~m-selig/ads/aircraft.html Detailed airfoil data is available for many sections at: http://amber.aae.uiuc.edu/~m-selig/ads.html From hrose-saa@ckdhr.com Sat Mar 17 08:33:30 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:30 From: James Robinson Subject: Re: Landing lights question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Disorganized Jeff wrote: > > At what point to landing lights get turned on and why at that point? > > I saw airliners approaching Pearson airport the other evening here in > Toronto and they had lights on quite some time prior to landing and I > wondered why so early since they can't serve much purpose until they are > right over the runway. It's not so much that the lights are used by the pilot to see where he is going, as it increases the aircraft's visibility to other traffic. It's the same reason why daytime running lights on your car are used: not so you can see where you are driving, but so other drivers can see your car better and not run into you. Some airlines have a policy that require pilots to turn on their landing lights whenever they are below a certain altitude. Sometimes the airport control tower will request the lights so the controller can see the aircraft as they closely approach the runway when VFR is being used. An sometimes the pilots will illuminate the lights themselves to help other aircraft see them. From hrose-saa@ckdhr.com Sat Mar 17 08:33:31 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:31 From: mitch21@northkent.freeserve.co.uk (Michael Mitchell) Subject: Re: Antonov at ORD? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newsg4.svr.pol.co.uk 984827618 10383 62.136.178.55 (17 Mar 2001 11:13:38 GMT) NNTP-Posting-Host: modem-55.elbereth.dialup.pol.co.uk Reply-To: mitch21@northkent.freeserve.co.uk In article , andrewsa@comm.mot.com (Andrew Sapuntzakis) wrote: > Driving by the "military" portion of O'Hare ~5pm on Jul 25, > I saw a large 4-engine, top-wing transport. The body was all-white > and the tail had blue-and-white "Antonov Design Bureau" livery. > Any ideas which model this was (225?) and why it's there? It is the AN 124. When they land at Manston in the UK they back 38 tonne trucks right inside to load up. The AN225 has 6 engines and there is only one airworthy at the moment. See:-http://www.aircraft-agency.de/an-124.htm http://www.airfoyle.co.uk/ http://www.west.net/~brianl/ruslan.htm Regards, Mike Mitchell. From hrose-saa@ckdhr.com Sat Mar 17 08:33:32 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:32 From: Matt Weber Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="us-ascii"; format=flowed At 20:03 15/03/01 +0000, you wrote: >BTW: Great to see this newsgroup working again. > >Congratulations to the moderator. :-) >On Tue, 25 Jul 2000 21:57:48 +0200, Helen Rose wrote >(in message ): > > The usual eyewitness reports have surfaced about the plane being alight > > before crashing (which appear to be correct, at least from the photos > > that I have viewed). >According to some recent eyewhitness reports, the engines were already on >fire while the aircraft was still on the runway, but it was already beyond >the 'point of no return'. It seems that in this case, however, the >'default' option to take off with was the less good choice. But obviously >the pilot had no chance to know that. :-( >Question to the more competent people here: How 'flyable' would a Concorde >with two failed engines (on one side) be. I thought I've read somewhere >that during the original trials, the manufacturers had to make the >experience that the loss of one engine already made the aircraft yaw quite >lot. So with both engines on one side lost, I guess there might have been >problems with the other two no longer getting enough air in the intakes? The speed/drag characteristics of Concorde are quite unusual. If you ever end up below about 275kt on 2 engines, you are in a black hole in the flight envelope. Drag exceeds available thrust, so unless you can convert altitude to airspeed, it is a death trap. The aircraft slows, forcing more noise up attitude, which further increases drag.... On most aircraft, minimum drag is usually quite close to V2, on Concorde at MGTOW it is about 415kt! The result is a low speed loss of two engines at low altitude is a guaranteed catastophe... From hrose-saa@ckdhr.com Sat Mar 17 08:33:33 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:33 From: "Antoin Daltun" Subject: Re: help! for seaplane in the "sea of Galilee" in the1930's. References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit > I'm looking for information about the " Imperial Airways" seaplane > landing in the sea of Galilee ,(as a stop in the regular route > between England and India in the 1930's ?) According to August 1939 OAG, from April 1939 Imperial Airways operated Southampton-Marseilles-Rome-Brindisi-Athens-Alexandria-Tiberias-Habbaniyeh (Baghdad)-Basra-Bahrein-Dabai (Sharjah)- Karachi-Raj Samand-Gwalior-Allahabad-Calcutta-Akyab-Rangoon-Bangkok-Penang-Singapore-Sou rabaya-Darwin-Townsville-Gladstone-Brisbane-Sydney with a call "at the following places if inducement offers and circumstances permit: St Nazaire, Mirabella, Jiwani, Batavia, Bima and Karumba" The aircraft were Short C Class flying-boats. Beyond Singapore flights were operated by Qantas aircraft. Ex Southampton, flights operated Wed, Sat, Sun. Mon, Thu flights operated as far as Calcutta only. Some flights used landplanes Alexandria-Karachi. Flights departed Southampton at 0500 would overnight Athens and depart Tiberias 1230 next day (arrival time not given, but dp Alexandria was 0930). Source is: Birth of an Industry: a nostalgic collection of airline schedules 1929-39 in facsimile, intro by Robert J Serling, published by Reuben H Donnelley Corp, publishers of OAG, in 1969. 1939 is the first year when detailed international schedules appear. Antoin Daltun From hrose-saa@ckdhr.com Sat Mar 17 08:33:34 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:34 From: RWM Subject: Re: Gurney Flaps References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: R.W. Mann & Company, Inc. URL http://www.RWMann.com/ Ali Hegazi wrote: > I am currently conducting studies into the effectiveness of gurney flaps > as high lift devices on swept wings in particular... I would greatly > appreciate any information about this topic or on gurney flaps in > general, that anyone might have... Most use of these sorts of "tuning" devices (Gurney, Liebeck, etc.) are in low Reynolds Number applications, sailplanes, wind turbines and high performance automotive, i.e. F1 and prototype sports cars. A predecessor and close relative is Douglas' trailing edge wedge, which was used on the MD11 among others. - Bob Mann -- R.W. Mann & Company, Inc. > Airline Industry Analysis and Consulting Port Washington, NY 11050 > tel 516-944-0900, fax 516-944-7280 mailto:info@RWMann.com > URL http://www.RWMann.com/ From hrose-saa@ckdhr.com Sat Mar 17 08:33:35 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:35 From: djb0x1312fc9@scream.org (Dan) Subject: Re: Strange 707 at Burbank References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: mochi.lava.net 963612102 26271 198.151.213.3 (14 Jul 2000 22:01:42 GMT) NNTP-Posting-Host: v2000.scream.org Reply-To: djb0x1312fc9@scream.org Stuart Feigin wrote: > I saw a very strange looking 707 yesterday at the > Burbank airport. I glanced out the window and saw > a 707 with enormous winglets taxi by. Not the > little fences like on an A320, but 6 or 7 foot > tall winglets like on a 747-400. The fuselage > lettering said something like "Stage III 707" and > the was an emblem with the letters "SI" on the > tail. The engines were the old pure turbojet > type, not the later turbo fans. > > Anyone know what I saw, and why it was built? I > can't imagine there is much economic value left in > ancient 707s. I poked around a little at www.airliners.net (in the search form pick Boeing 707/720 from the aircraft pulldown, and enter "stage" in the keyword box) and found some photos of Stage III 707's, a.k.a. 707-3J6B, quite possibly including the very one you saw. That one appears to be owned by Quiet Skies Inc. The "Stage 3" apparently has something to do with the engines complying with something or other... ah, there we go, compliance with Federal Aviation Regulation Part 36, aircraft noise levels. Stage III is the new-technology, quiet jet stuff that the FAA requires starting this year. So apparently these folks retrofitted the engines on an ol' 707 to make them comply with the latest regulations. Why the winglets? No idea. Maybe the engine changes impacted the aircraft's behavior enough that they were warranted? -Dan -- Dan Birchall - Palolo Valley, Honolulu HI - http://dan.scream.org Get paid for your opinions - http://epinions.scream.org/join.html My address expires - take out the hex stamp if your reply bounces From hrose-saa@ckdhr.com Sat Mar 17 08:33:36 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:36 From: emtgx@aol.com (J. G. Pastorkyna) Subject: Folding wings 777? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: AOL http://www.aol.com Has any carrier taken advantage of Boeing's offer to manufacture the 777 with wings that can be shortened by folding up before reaching the gate? It was mentioned in a TV documentary, but I certainly haven't seen such a sight anywhere. Are there that many airports gates where such a practise would be helpful? ------------------- J. G. Pastorkyna From hrose-saa@ckdhr.com Sat Mar 17 08:33:37 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:37 From: The Worrier King Subject: SAAB-2000 Powered Evevator Control System Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: MTkgTm9BdXRoVXNlciBURUxPQ0lUWS1SRUFERVJTIDY0LjE5Mi44OS4zMyAgVHVlLCAyMCBKdW4g!MjAwMCAxNDo0Njo1NiBQRFQ= X-Newsreader: Forte Agent 1.8/32.548 When I was a software engineer at Martin Marietta I worked on the Powered Elevator Control Unit for the SAAB-2000 turboprop. SAAB planned to produce a small number of planes without this system, then add it to planes on the production line. However, I left the company before the system made it into production aircraft. Does anyone know which production aircraft have the PECS and which ones have the old manual elevator system? I think only Crossair got the manual system on a few planes. I've found a number of photos online, nut I cant see any difference in the elevator configuration on any of them. "I believe in the fundamental interconnectedness of things" -- Dirk Gently (by Douglas Adams) From hrose-saa@ckdhr.com Sat Mar 17 08:33:38 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:38 From: "Titch" Subject: E.G.P.W.S. Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news2-win.server.ntlworld.com 960942219 62.252.136.20 (Wed, 14 Jun 2000 01:23:39 BST) X-Newsreader: Microsoft Outlook Express 5.00.2314.1300 Organization: ntlworld News Service NNTP-Posting-Host: 62.252.136.20 I am currently working installing Aillied Signal EGPWS mod on Boeing 737 aircraft and was wondering if any one else is doing the same mod to their aircraft. Titch From hrose-saa@ckdhr.com Sat Mar 17 08:33:39 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 17 Mar 2001 08:33:39 From: "Jeff" Subject: airplane watching questions Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news2.rdc1.on.home.com 960765572 24.114.185.85 (Sun, 11 Jun 2000 16:19:32 PDT) X-Newsreader: Microsoft Outlook Express 5.00.2615.200 Organization: @Home Network Canada NNTP-Posting-Host: 24.114.185.85 Hello folks. I indulged myself today in driving out to Pearson airport here in Toronto Canada to watch planes land. I had a fun time but came up with a few questions I hope someone (or someone_s_) can answer. 1. Most of the airliners seemed to follow an identical path down to the runway but every so often one would tip its wings back and forth a little bit on the approach. Were the planes that were making these adjustments making manual landings and the others making computerized landings? What proportion of airliner landings at an airport like Pearson International are flown automatically by a computer locked onto a beam? 2. It was a cool afternoon (temp had dropped to about 12 C) and very humid (raining on and off and very low cloud cover). Most of the planes landing had a streamer of water vapor trailing from the wingtips like smoke streamers and some had a cloud of vapor on the upper surface of the wings. Someone once explained this to me and I forget what it is. Something to do with low pressure around the wing? 3. I've always noted that the larger the airliner, the slower it appears to be moving in the air. Today, the big planes seemd to be slowly settling out of the sky and the occasional executive-type jet appeared to be 'whistling' down out of the sky. Is this an optical illusion? I am assuming it is and may have to do with the fact that a long plane takes longer to travel its own length than a shorter one? Thanks in advance to anyone who can take a crack at any or all of these questions! Jeff From hrose-saa@ckdhr.com Sun Mar 18 12:06:09 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:09 From: John Liebson Subject: Re: Folding wings 777? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: reader.nmix.net 984939562 35776 198.59.168.170 (18 Mar 2001 18:19:21 GMT) Organization: NMIX X-Newsreader: Forte Agent 1.8/32.548 NNTP-Posting-Host: dialup70.nets.com emtgx@aol.com (J. G. Pastorkyna) wrote: >Has any carrier taken advantage of Boeing's offer to manufacture the 777 with >wings that can be shortened by folding up before reaching the gate? It was >mentioned in a TV documentary, but I certainly haven't seen such a sight >anywhere. Are there that many airports gates where such a practise would be >helpful? No 777s have been built with that feature. It was studied as a request mainly from American Airlines, which then declined to buy its 777s with the folding wingtips. From hrose-saa@ckdhr.com Sun Mar 18 12:06:10 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:10 From: don@news.daedalus.co.nz (Don Stokes) Subject: Re: airplane watching questions References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: raewyn.paradise.net.nz 984916432 75838 203.96.144.16 (18 Mar 2001 11:53:52 GMT) Organization: Daedalus Consulting X-Newsreader: trn 4.0-test72 (19 April 1999) NNTP-Posting-Host: 203-96-144-16.cable.paradise.net.nz In article , Jeff wrote: >1. Most of the airliners seemed to follow an identical path down to the >runway but every so often one would tip its wings back and forth a little >bit on the approach. Were the planes that were making these adjustments >making manual landings and the others making computerized landings? What >proportion of airliner landings at an airport like Pearson International are >flown automatically by a computer locked onto a beam? I'm not sure how gross autoland corrections can be, but note that most autoland systems don't autopilot down to the deck -- the flare and rollout are controlled by the crew. The next level up has the autopilot working until touchdown, and only the most advanced (expensive) include control of rollout. I've heard lots of anecdotes to the effect that pilots very much prefer to hand-fly the landings, leaving the autoland only for really marginal conditions. Given that, it seems likely that most of the approaches you see are manual, and if the crew got the approach vector right (and the wind didn't upset things), you don't see gross corrections, and if they didn't, you do. >2. It was a cool afternoon (temp had dropped to about 12 C) and very humid >(raining on and off and very low cloud cover). Most of the planes landing >had a streamer of water vapor trailing from the wingtips like smoke >streamers and some had a cloud of vapor on the upper surface of the wings. >Someone once explained this to me and I forget what it is. Something to do >with low pressure around the wing? High pressure air can hold more water vapour (ie water in its colourless gaseous state) than low pressure air. If the air is close to saturation (ie the maximum amount of water vapour it can hold for the given pressure), lowering the pressure causes water to condense into tiny water droplets, which form the vapour trails. Wings have lower pressure on top (higher underneath), especially over the flaps -- you often see vapour trails coming off the outboard corners of the flaps on approach in humid weather, as this is a point on the wing which is at particularly low pressure. >3. I've always noted that the larger the airliner, the slower it appears to >be moving in the air. Today, the big planes seemd to be slowly settling out >of the sky and the occasional executive-type jet appeared to be 'whistling' >down out of the sky. Is this an optical illusion? I am assuming it is and >may have to do with the fact that a long plane takes longer to travel its >own length than a shorter one? You got it exactly. Jets from bizjets to widebody airliners tend to fly at speeds pretty much in the same ballpark, so smaller planes seem to fly faster because they cover their own length more quickly. -- don From hrose-saa@ckdhr.com Sun Mar 18 12:06:11 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:11 From: "Robert H. Nielsen" Subject: Re: Folding wings 777? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: bgtnsc04-news.ops.worldnet.att.net 984894473 12.82.152.178 (Sun, 18 Mar 2001 05:47:53 GMT) Organization: AT&T Worldnet NNTP-Posting-Host: 12.82.152.178 "J. G. Pastorkyna" wrote: > Has any carrier taken advantage of Boeing's offer to manufacture the > 777 with wings that can be shortened by folding up before reaching > the gate? It was mentioned in a TV documentary, but I certainly > haven't seen such a sight anywhere. Are there that many airports > gates where such a practise would be helpful? This idea was fielded when the 777 was being designed, apparently at the specific request of American which thought the wingspan would be a problem at certain airports. It was never put into the manufacturing process and is not now offered on 777s (though actual wings were constructed and tested.) A Boeing engineer I worked with told me, "That was the best thing we ever did. We went far enough with the design so that the customer really could see what it would cost in fuel burn, weight increase, and mechanical complexity, and they realized it wasn't really a good idea." Apparently airline planners like to dream up technologies, and don't like to be told by manufacturers that some concepts are impractical. But enough solid engineering can convince even the skeptics. A side benefit of this idea is that the folding wingtips were designed to be dry, and now the space is used for fuel in the longer range versions of the airplane. Regards, Retired Robert From hrose-saa@ckdhr.com Sun Mar 18 12:06:12 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:12 From: "BrianM" Subject: Re: Aircraft identity References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: tor-nn1.netcom.ca 984891792 216.129.77.108 (Sun, 18 Mar 2001 00:03:12 EDT) Organization: AT&T Canada IES X-Newsreader: Microsoft Outlook Express 4.72.2106.4 NNTP-Posting-Host: 216.129.77.108 Stephens Lyle E wrote in message ... >I'm trying to identify two aircraft in a photo taken at Moline, IL in the >1930's. The registrations numbers are NC726K and NC727K. Both aircraft have >2 of almost everything: wings, engines, fins and rudders, stabs and >elevators. Is there a historic registration database I can consult? Yes there is: http://aerofiles.com/regs-home.html They were Curtiss Condors. Brian From hrose-saa@ckdhr.com Sun Mar 18 12:06:13 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:13 From: David Brunner Subject: Re: Folding wings 777? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: wormhole.dimensional.com 984872061 206.124.29.6 (Sat, 17 Mar 2001 16:34:21 MST) Organization: Nyx NNTP-Posting-Host: 206.124.29.6 J. G. Pastorkyna wrote: > Has any carrier taken advantage of Boeing's offer to manufacture the > 777 with wings that can be shortened by folding up before reaching > the gate? The way I heard it, the mechanism for folding the wingtips weighs quite a bit and the airlines preferred to have that weight allocated to paying passengers, rather than the wingtip-folding machinery. I saw the only example of the folding wingtip at Boeing's little museum at Paine Field in Everett. From hrose-saa@ckdhr.com Sun Mar 18 12:06:14 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:14 From: "James Weber" Subject: Re: airplane watching questions Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit >2. It was a cool afternoon (temp had dropped to about 12 C) and very humid >(raining on and off and very low cloud cover). Most of the planes landing >had a streamer of water vapor trailing from the wingtips like smoke >streamers and some had a cloud of vapor on the upper surface of the wings. >Someone once explained this to me and I forget what it is. Something to do >with low pressure around the wing? The vortex behind the wings tips are in fact low pressure areas. The sudden reduction in pressue without doing 'work' is called adiabic expansion, which cools the air. If the relative humidity is very high, the lower temperature can cause the relative humidity to exceed 100%, at which point the water condeses out, and you get instant cloud formation..... It the humidity is high enough, you can also get it toward the back of the upper wing surface. Shock wave from a supersonic aircraft does the same thing. Low pressure behind the wave causes cloud formation, so you can see an aircraft that seems to be draped in cloud....... From hrose-saa@ckdhr.com Sun Mar 18 12:06:15 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:15 From: "James Weber" Subject: Re: Folding wings 777? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit -----Original Message----- From: J. G. Pastorkyna To: airliners@chicago.com Date: 18 March 2001 03:49 Subject: Folding wings 777? >Has any carrier taken advantage of Boeing's offer to manufacture the >777 with wings that can be shortened by folding up before reaching >the gate? There have been no 'takers', and as far as I know, Boeing withdrew the feature about 18 months ago..... From hrose-saa@ckdhr.com Sun Mar 18 12:06:16 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:16 From: Matt Weber Subject: Re: Strange 707 at Burbank References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="us-ascii"; format=flowed >So apparently these folks retrofitted the engines on an ol' >707 to make them comply with the latest regulations. Why the >winglets? No idea. Maybe the engine changes impacted the >aircraft's behavior enough that they were warranted? The winglets reduce the parasitic drag a few per cent. As long as you have to tweak the engines and flaps and slat scheduling, for a few dollars more, you can squeeze few per cent better fuel economy as well. Many of the stage III upgrades either reduce engine thrust, or reduce MGTOW, so reducing fuel burn in flight is one way of recovering the last payload. From hrose-saa@ckdhr.com Sun Mar 18 12:06:17 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:17 From: megazone@sidehack.sat.gweep.net (MegaZone) Subject: Re: Folding wings 777? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: UmFuZG9tSVanoLdWSDtuZ/kcEoIKYEe1tpt2ng380YgT4TIk4kiXnuNOwQk4Jw5U Organization: WPI Discordian Society, Undocumented Cabal of the Accursed Saint Shiranto Joe X-Newsreader: trn 4.0-test74 (May 26, 2000) emtgx@aol.com (J. G. Pastorkyna) shaped the electrons to say: >Has any carrier taken advantage of Boeing's offer to manufacture the 777 with >wings that can be shortened by folding up before reaching the gate? It was Nope. And Boeing has dropped that option. It was included basically because American Airlines said they wouldn't buy any 777s if they couldn't fit them into gates they had. And that required the folding wing... Then American didn't order the folding wing 777 anyway. No one else expressed interest, and as they grew the line they would have had to keep investing engineering in the option, so they just dropped it. -MZ, CISSP #3762, RHCE #806199299900541 -- Gweep, Discordian, Author, Engineer, me.. "A little nonsense now and then, is relished by the wisest men" 781-788-0130 Hail Discordia! From hrose-saa@ckdhr.com Sun Mar 18 12:06:18 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:18 From: James Robinson Subject: Re: airplane watching questions References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Disorganized Jeff wrote: > > 1. Most of the airliners seemed to follow an identical path down to the > runway but every so often one would tip its wings back and forth a little > bit on the approach. Were the planes that were making these adjustments > making manual landings and the others making computerized landings? The adjustments are in reaction to various cross winds encountered on the approach. It wouldn't matter if the landing was automatic or manual, the aircraft would still react the same way. > What proportion of airliner landings at an airport like Pearson > International are flown automatically by a computer locked onto a beam? Virtually no landings are automatic. The pilot will usually take manual control from the autopilot on the final approach to landing. > 2. It was a cool afternoon (temp had dropped to about 12 C) and very humid > (raining on and off and very low cloud cover). Most of the planes landing > had a streamer of water vapor trailing from the wingtips like smoke > streamers and some had a cloud of vapor on the upper surface of the wings. > Someone once explained this to me and I forget what it is. Something to do > with low pressure around the wing? Exactly. The low pressure will cause the moisture in the air to condense into a fog when conditions are right. Lower pressure air will hold less moisture than higher pressure air, so when the relative humidity of ambient air is high enough, the sudden lowering of pressure will cause some of the moisture to condense and become visible. This is the case at wingtips, at the tips of propellers at times, behind canopies on military aircraft, and over the top of wings. > 3. I've always noted that the larger the airliner, the slower it appears to > be moving in the air. Today, the big planes seemd to be slowly settling out > of the sky and the occasional executive-type jet appeared to be 'whistling' > down out of the sky. Is this an optical illusion? I am assuming it is and > may have to do with the fact that a long plane takes longer to travel its > own length than a shorter one? It's just an optical illusion. Large aircraft don't seem to be travelling as fast as smaller aircraft, but they are in reality. From hrose-saa@ckdhr.com Sun Mar 18 12:06:19 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:19 From: Tobias Schnell Subject: Re: Landing lights question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Forte Agent 1.6/32.525 On 16 Mar 2001 05:56:20 , "Jeff" wrote: >At what point to landing lights get turned on and why at that point?> >I saw airliners approaching Pearson airport the other evening here in >Toronto and they had lights on quite some time prior to landing and I >wondered why so early since they can't serve much purpose until they are >right over the runway. Normally they are switched on somewhere during descend, between 5000 and 10000 ft. The purpose is to make the aircraft more visible for other aircraft in the vicinity of airports, where traffic is usually dense. They are also supposed to help in preventing birdstrikes. These are the reasons why they are also used during daytime. Tobias From hrose-saa@ckdhr.com Sun Mar 18 12:06:20 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:20 From: Pete Finlay Subject: Re: Concorde tyres References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Expensive Desktop Paperweights X-Newsreader: Turnpike (32) Version 4.01 Reply-To: Pete Finlay In article , Pete Mellor writes >Dear all, > >There have been a number of different reports about how (and/or "if") >tyre failure contributed to the recent crash of Concorde. > >A few queries to the list:- > >1. How come *any* aircaft tyre fails catastrophically? Surely fuse > plugs should ensure that a tyre fails in a controlled and > predictable fashion if overstressed? Sometimes, but not always. Aircraft tyres are usually inflated to anywhere up to 230 p.s.i. All it takes is something to puncture the rubber. >2. One newspaper reported that experts from the Goodyear Co. had > flown in from the US to assist the investigation. Presumably > this is because Goodyear supplied the tyres for Concorde? Maybe for the Air France aircraft. >3. A friend of mine claims to have heard a report on a news bulletin > (which I did not hear myself, and have been unable to confirm from > press reports) that the French and British fleets use different > tyres, hence the willingness of BA to continue flights while > Air france keeps its fleet grounded. Does anyone know anything > about this? BA uses different tyres from Air France. That was not the only reason BA kept flying after the crash. Until the preliminary findings were released by the French, there was no reason to ground the BA aircraft. They operate under a different C. of A. >4. As a variant on 3 above, a more recent report had it that the > French fleet had retained some sort of "cover" on the bogies > that had been removed from the British fleet in a modification > following an early incident in which it contributed to the > rupture of a fuel tank or line after a tyre blow-out. Again, > does anyone know anything? The report was wrong. There is a water deflector fitted in front of each bogie. BA modified their water deflectors by strengthening them quite a few years ago. The French did not. regards -- Pete Finlay From hrose-saa@ckdhr.com Sun Mar 18 12:06:21 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:21 From: "James Weber" Subject: Re: Antonov at ORD? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit -----Original Message----- From: Andrew Sapuntzakis To: airliners@chicago.com Date: 16 March 2001 15:17 Subject: Antonov at ORD? >Driving by the "military" portion of O'Hare ~5pm on Jul 25, >I saw a large 4-engine, top-wing transport. The body was all-white >and the tail had blue-and-white "Antonov Design Bureau" livery. >Any ideas which model this was (225?) and why it's there? 225 has 6 engines, so it is an AN-124, and they are routinely used for freight charters that carry outsize heavy cargo, often operated by Volga-Dnepr, or Heavilift. From hrose-saa@ckdhr.com Sun Mar 18 12:06:22 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 18 Mar 2001 12:06:22 From: "John R Weiss" Subject: Re: Landing lights question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Trace: news1.sttls1.wa.home.com 984805561 24.20.159.158 (Fri, 16 Mar 2001 21:06:01 PST) Organization: Excite@Home - The Leader in Broadband http://home.com/faster X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Reply-To: "John R Weiss" NNTP-Posting-Host: 24.20.159.158 "Jeff" wrote in message news:airliners.2001.4@ditka.Chicago.COM... > I'm not sure if this newsgroup is active or open to public posting but I > have a question. > > At what point to landing lights get turned on and why at that point? At 10,000' according to our Flight Ops Manual... More VFR and other uncontrolled/unmonitored aircraft below 10K. -- John Weiss Seattle, WA remove *nospam* from reply address From hrose-saa@ckdhr.com Wed Mar 21 18:33:22 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:22 From: "Matthew Willshee" Subject: Re: Aircraft design question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news8.svr.pol.co.uk 985215204 30684 62.25.162.16 (21 Mar 2001 22:53:24 GMT) X-Newsreader: Microsoft Outlook Express 5.00.2314.1300 NNTP-Posting-Host: modem-528.hodad.dialup.pol.co.uk Dafydd ab Hugh wrote in message news:airliners.2001.3@ditka.Chicago.COM... > Dear aerospace engineers; > > My wife is an aerospace engineering student at Cal Poly Pomona, and > for her senior thesis, she is supposed to design a passenger window > for a future single-stage-to-orbit (SSTO) vehicle. This vehicle would > take some number of passengers from a vertical takeoff into orbit or a > suborbital arc and back down to a horizontal landing on a commercial > airport runway. Think of Reagan's 1980s proposal of an "Orient > Express." > But she's been unable to find any publications that discuss designing > passenger windows on commercial jets, hypersonic aircraft, spacecraft, > or anything else. > There must be something out there; engineers build airplanes with > passenger windows, so somebody knows how to design them! The windows will probably be glass, which is a ceramic. I have tried to give a summary of the strength issues below. The source is "Engineering Materials 2" by M.F.Ashby and D.R.H.Jones. I would recommend this book - it is very readable. There is a good explanation of the issues involved in designing with ceramics and even a case study on pressure window design in there. You cannot think of ceramics of having a failure strength as such - they have a probability of failure at a given stress. The variation depends on both stress and volume and can be described by a Weibull distribution: loge (Probability of survival) = - (V/V0) * (sigma/sigma0)^m loge is logarithm to the base e m = Weibull exponent (about 10 for glass). Sigma0 and m are experimental constants found by testing batches of samples of volume V0 (there are some example values in the book and I guess any materials text would have something similar). Sigma0 is the stress at which a batch of samples of volume V0 would have a probability of survival of 1/e. Why do we have to use probability? The failure strength is set by the size of flaws or cracks in the material. how large the cracks in a given piece are is purely down to chance. This also explains why volume has an effect. A larger piece of material has a greater chance of having a given size of crack. That is not the whole story - cracks grow over time under stress so any window will break eventually under any stress. The book gives ( sigma / sigma test )^n = (t test) / t n = slow crack growth exponent - about 10 for glass. Armed with this we can make an attempt at sizing the glass. Pick a design lifetime (1000's of hours) and an acceptable probability of failure (a very small number such as 1/1 000 000 000). Get some materials data which will have some sort of failure stress. Use the time equation to factor the stress based on the experimental test time for the materials data and your design life time. Factor again using the Weibull equation and your design probability of survival (1- acceptable failure probability) to get an acceptable stress in your window. Consider a stress safety factor, which will further reduce your maximum allowable stress. Finally pick a geometry so that you can relate the pressure load on the window to stress. Stresses for simple geometries like plane circles and hemispheres should be available in tables. The thickness of window for a given size should then come out of the equation. It will probably be necessary to make assumptions and there won't be any one right answer. This is what engineering design is about. Regards, Matthew Willshee From hrose-saa@ckdhr.com Wed Mar 21 18:33:23 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:23 From: westin*nospam@graphics.cornell.edu (Stephen H. Westin) Subject: Re: Concorde tyres References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news01.cit.cornell.edu 985193475 7968 128.84.247.211 (21 Mar 2001 16:51:15 GMT) Organization: Cornell University X-Newsreader: Gnus v5.7/Emacs 20.6 NNTP-Posting-Host: diesel.graphics.cornell.edu Pete Mellor writes: > 1. How come *any* aircaft tyre fails catastrophically? Surely fuse > plugs should ensure that a tyre fails in a controlled and > predictable fashion if overstressed? As we now know, it is thought that the tire was cut by a piece of metal on the runway. At that point, it's entirely possible that pieces of the tire flew out at high speed, regardless of inflation pressure. > 2. One newspaper reported that experts from the Goodyear Co. had > flown in from the US to assist the investigation. Presumably > this is because Goodyear supplied the tyres for Concorde? Or perhaps they have some special expertise that would be useful, or a unique testing facility. -- -Stephen H. Westin Any information or opinions in this message are mine: they do not represent the position of Cornell University or any of its sponsors. From hrose-saa@ckdhr.com Wed Mar 21 18:33:24 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:24 From: "Steve Johnston" Subject: Re: Deice References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newssvr06-en0.news.prodigy.com 985140569 4070779 209.156.148.11 (21 Mar 2001 02:09:29 GMT) Organization: Prodigy http://www.prodigy.com X-Newsreader: Microsoft Outlook Express 5.00.2314.1300 NNTP-Posting-Host: a010-0011.klmz.splitrock.net David Pinella wrote in message news:airliners.2001.6@ditka.Chicago.COM... > I was on a Canadair RJ yesterday. I think this is the first time that I > have been on a plane that was deiced. I have a question. How much does > deicing cost for a plane like this? A 747? How many gallons? Is it > recycled? It looked like they used a pink spray and then a green spray. > I assume the red is a deice and the green is an anti ice, like ethelyne > glycol. It stuck really nice to the wing, very pretty. What was the red? Cost varies depending on how much glycol is applied, the average cost ranges from 4 to 8 dollars per gallon in concentrate form. Deicing fluid is diluted, usually about 50/50, anti-icing is applied at 100% concentration. A CRJ would take as little as 30-50 gallons for frost and up to several hundred gallons for heavy snow or ice. a 747 would take much more. Most airports require recovery but not necessarily recycling. Both are glycol just different formulations and either ethylene or propylene based. Anti-ice or type 4 is very thick and sticks to the surfaces until it is sheared off during the takeoff roll. Steve From hrose-saa@ckdhr.com Wed Mar 21 18:33:25 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:25 From: inet@intellisys.net (brian whatcott) Subject: Re: Landing lights question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: BWInc X-Newsreader: Forte Free Agent 1.21/32.243 Reply-To: inet@intellisys.net NNTP-Posting-Host: news.newsdawg.com On 16 Mar 2001 05:56:20 , "Jeff" wrote: >I'm not sure if this newsgroup is active or open to public posting but I >have a question. >At what point to landing lights get turned on and why at that point? A prior-to-landing check list will touch on the need for landing lights. For aircraft depending on see and be seen, the early use of landing lights in high density traffic areas is seen as a safety measure. Brian Whatcott Altus OK Eureka! From hrose-saa@ckdhr.com Wed Mar 21 18:33:26 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:26 From: inet@intellisys.net (brian whatcott) Subject: Re: Lightning Strike out of Dorval ? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: BWInc X-Newsreader: Forte Free Agent 1.21/32.243 Reply-To: inet@intellisys.net NNTP-Posting-Host: news.newsdawg.com On 16 Mar 2001 05:56:21 , rfspecialist@home.com (Joe) wrote: > At first I thought it was a bomb but then attributed it to a direct >Lightning strike. About 5 minutes followed when the captain came back >on and said what we encountered was not a Lightning Strike but a >Static Discharge and all systems were OK. Should he not have turned >back to be safe? What is the procedure for this? You cannot tell from >the cockpit if structural damage occured. The usual result of a lightning strike on a metal skin airplane is one or more small holes at the entry and exit locations, where the current density is specially high. Composite skin airplanes can be more problematic. Brian Whatcott Altus OK Eureka! From hrose-saa@ckdhr.com Wed Mar 21 18:33:27 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 21 Mar 2001 18:33:27 From: Malcolm Weir Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Forte Agent 1.8/32.548 Organization: Little to None NNTP-Posting-Host: !X/'>1k-W.otP],FV&,(F;\K3 (Encoded at Airnews!) On 16 Mar 2001 05:56:29 , Wolfgang Keller caused to appear as if it was written: [ Snip ] >Question to the more competent people here: How 'flyable' would a Concorde >with two failed engines (on one side) be. I thought I've read somewhere >that during the original trials, the manufacturers had to make the >experience that the loss of one engine already made the aircraft yaw quite >lot. So with both engines on one side lost, I guess there might have been >problems with the other two no longer getting enough air in the intakes? All indications are that the thing was flyable in the sense that it was above the control speeds for its configuration. It lacked the speed to climb, though. [ Snip ] Malc. From hrose-saa@ckdhr.com Wed Mar 21 18:33:28 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:28 From: "James Weber" Subject: Re: Concorde tyres Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit >The report was wrong. There is a water deflector fitted in front of each >bogie. BA modified their water deflectors by strengthening them quite a >few years ago. The French did not. Don't think strengthened is a good description for what they did, because the BA ones will break just as easily as the AF versions, however when the BA one's break, they will remain attached to the airframe. The Water deflector is basically an empty pipe, and mod consists of running a high strength cable through the hollow portion, so if the pipe breaks apart, the cable holds the pieces to the airframe.... From hrose-saa@ckdhr.com Wed Mar 21 18:33:29 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:29 From: Carl Peters Subject: Re: airplane watching questions References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Jeff wrote: > Hello folks. > > I indulged myself today in driving out to Pearson airport here in Toronto > Canada to watch planes land. > > I had a fun time but came up with a few questions I hope someone (or > someone_s_) can answer. > > 1. Most of the airliners seemed to follow an identical path down to the > runway but every so often one would tip its wings back and forth a little > bit on the approach. Were the planes that were making these adjustments > making manual landings and the others making computerized landings? What > proportion of airliner landings at an airport like Pearson International are > flown automatically by a computer locked onto a beam? 1. Regarding landings, pilots will do both - use autopilots at times, and hand fly. Regarding what you saw, either 'mode' could have been in effect, and the planes that "would tip its wings" were probably responding to some cross winds. A wind coming in from one side will generate extra lift on the same side wing, with a mild decrease in lift to the opposite wing, as it is partially in the wind 'shadow' created by the interfering fuselage. Ailerons will be used, whether by the pilot or autopilot to bring the wings back level. > 2. It was a cool afternoon (temp had dropped to about 12 C) and very humid > (raining on and off and very low cloud cover). Most of the planes landing > had a streamer of water vapor trailing from the wingtips like smoke > streamers and some had a cloud of vapor on the upper surface of the wings. > Someone once explained this to me and I forget what it is. Something to do > with low pressure around the wing? 2. The vapor you saw is usually seen in humid conditions as you describe, and is the result of water condensing into a cloud by the lowered pressure over the top of a wing, and in the center of a vortex, as seen emanating from wing tips or the flap edges (I have seen many off the far flap outside trailing edge on the 737 while flying, many off the wingtip, and several times a vertical vortex below the leading lower edge of a wing mounted engine - L1011 and 767). For the same reasons, the effect is also noted by survivors of sudden cabin depressurization, where a sudden fog develops in the cabin. > 3. I've always noted that the larger the airliner, the slower it appears to > be moving in the air. Today, the big planes seemd to be slowly settling out > of the sky and the occasional executive-type jet appeared to be 'whistling' > down out of the sky. Is this an optical illusion? I am assuming it is and > may have to do with the fact that a long plane takes longer to travel its > own length than a shorter one? 3. The short answer is that you are being fooled by an illusion. A 747, depending on many variables, will land at a similar or slightly higher landing speed than a 737, for example. Carl Peters From hrose-saa@ckdhr.com Wed Mar 21 18:33:30 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:30 From: Carl Peters Subject: Re: Folding wings 777? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM "J. G. Pastorkyna" wrote: > Has any carrier taken advantage of Boeing's offer to manufacture the 777 with > wings that can be shortened by folding up before reaching the gate? It was > mentioned in a TV documentary, but I certainly haven't seen such a sight > anywhere. Are there that many airports gates where such a practise would be > helpful? The folding wings were designed as a feature to allow the 777 to use 767 and even smaller sized parking stands. American Airlines drove this design the most, yet did not opt for it upon placing an order. To date, no one else has either. Cons of the system are substantial weight penalties, public acceptance, and the lack of need as the 777 has fit in well to existing airport stands. At this point, I don't know if Boeing is even offering the option. Carl Peters From hrose-saa@ckdhr.com Wed Mar 21 18:33:31 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:31 From: Philip Morten Subject: Re: help! for seaplane in the "sea of Galilee" in the1930's. References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: BT Internet NNTP-Posting-Host: host213-1-166-200.btinternet.com Ben-Yosef wrote: > > I'm looking for information about the " Imperial Airways" seaplane landing > in the "sea of Galilee" ,(as a stop in a > regular route between England and India in the 1930's ?) > who knows??? This is to be described in several accounts as at Tiberias, as far as I can make out this was just a refuelling stop between Alexandria and Lake Habbaniyah. A route map published in The Aeroplane of 29 Sep 1938 (and reproduced in "Adventourous Empires"(*)) shows this but there is a reference in the text of the Dead Sea being used earlier due to religous objections to the use of the Sea of Galilee. Philip Morten * Adventurous Empires - The Story of the Short Empire Flying Boats, Philip E Simms, Airlife, 2000, ISBN 1-84037-130-7 From hrose-saa@ckdhr.com Wed Mar 21 18:33:32 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:32 From: Philip Morten Subject: Re: Aircraft identity References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: BT Internet NNTP-Posting-Host: host213-1-166-200.btinternet.com Stephens Lyle E wrote: > > I'm trying to identify two aircraft in a photo taken at Moline, IL in the > 1930's. The registrations numbers are NC726K and NC727K. Both aircraft have > 2 of almost everything: wings, engines, fins and rudders, stabs and > elevators. Is there a historic registration database I can consult? Those are Curtiss Type 53 Condor transports - first flown 1929, six built, used by Eastern Air Transport 1931-1934. See Curtiss Aircraft 1907-1947, Peter M Bowers, Putnam 1979, ISBN 0-85177-811-9 Philip Moren From hrose-saa@ckdhr.com Wed Mar 21 18:33:33 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 21 Mar 2001 18:33:33 From: don@news.daedalus.co.nz (Don Stokes) Subject: Re: Strange 707 at Burbank References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: raewyn.paradise.net.nz 984950125 88357 203.96.144.16 (18 Mar 2001 21:15:25 GMT) X-Newsreader: trn 4.0-test72 (19 April 1999) Organization: Daedalus Consulting NNTP-Posting-Host: 203-96-144-16.cable.paradise.net.nz In article , Matt Weber wrote: >The winglets reduce the parasitic drag a few per cent. As long as you have >to tweak the engines and flaps and slat scheduling, for a few dollars more, >you can squeeze few per cent better fuel economy as well. Many of the >stage III upgrades either reduce engine thrust, or reduce MGTOW, so >reducing fuel burn in flight is one way of recovering the last payload. The Burbank folks I talked to at Farnborough in '98 reckoned their 707 (JT3D) hushkits actually *improved* fuel burn, primarily due to the rebuilt inlets. But they built winglets anyway... -- don From hrose-saa@ckdhr.com Fri Mar 23 17:40:04 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:04 From: "John R Weiss" Subject: Re: Aircraft design question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Trace: news1.sttls1.wa.home.com 985299539 24.20.159.158 (Thu, 22 Mar 2001 14:18:59 PST) X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: Excite@Home - The Leader in Broadband http://home.com/faster NNTP-Posting-Host: 24.20.159.158 Reply-To: "John R Weiss" "Matthew Willshee" wrote in message news:airliners.2001.42@ditka.Chicago.COM... > Dafydd ab Hugh wrote in message > news:airliners.2001.3@ditka.Chicago.COM... > > There must be something out there; engineers build airplanes with > > passenger windows, so somebody knows how to design them! > The windows will probably be glass, which is a ceramic. Aircraft windshields are often made of laminates of acrylic and glass. Curved sections, like fighter canopies, are made of acrylic alone. I believe windows on deep submersibles have been made of quartz. -- John Weiss Seattle, WA remove *nospam* from reply address From hrose-saa@ckdhr.com Fri Mar 23 17:40:05 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:05 From: Pete Finlay Subject: Re: Concorde tyres References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Turnpike (32) Version 4.01 Organization: Expensive Desktop Paperweights Reply-To: Pete Finlay In article , James Weber writes > >>The report was wrong. There is a water deflector fitted in front of each >>bogie. BA modified their water deflectors by strengthening them quite a >>few years ago. The French did not. > >Don't think strengthened is a good description for what they did, because >the BA ones will break just as easily as the AF versions, however when the >BA one's break, they will remain attached to the airframe. The Water >deflector is basically an empty pipe, and mod consists of running a high >strength cable through the hollow portion, so if the pipe breaks apart, the >cable holds the pieces to the airframe.... Whatever. The end result is that BA's water deflectors are less prone to causing secondary damage to other parts of the aircraft. In the past, the break up of the water deflectors have caused problems, and they still do on aircraft without the cable modification. -- Pete Finlay From hrose-saa@ckdhr.com Fri Mar 23 17:40:06 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 23 Mar 2001 17:40:06 From: don@news.daedalus.co.nz (Don Stokes) Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: raewyn.paradise.net.nz 985233955 58107 203.96.144.16 (22 Mar 2001 04:05:55 GMT) X-Newsreader: trn 4.0-test72 (19 April 1999) Organization: Daedalus Consulting NNTP-Posting-Host: 203-96-144-16.cable.paradise.net.nz Malcolm Weir wrote: >All indications are that the thing was flyable in the sense that it was >above the control speeds for its configuration. It lacked the speed to >climb, though. Nope. For most of the flight, one of the port side engines was producing some power, albeit well below capacity due to damage. When that engine finally failed, the aircraft no longer had suffient power, at which point the aircraft stalled, yawing toward the port side and rolling over, and crashed. The crew did very well to get the plane on an emergency approach to Le Bourget on only 2 and a bit engines, but with the loss of the bit, the physics of the situation was against them. -- don From hrose-saa@ckdhr.com Fri Mar 23 17:40:07 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:07 From: "Mark Newman" Subject: Autoland systems Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news7.onvoy.net 959221450 137.192.59.4 (Wed, 24 May 2000 21:24:10 CDT) X-Newsreader: Microsoft Outlook Express 5.00.2314.1300 Organization: Onvoy NNTP-Posting-Host: 137.192.59.4 Hello, I've read that the avionics on modern airliners can handle almost the entire flight by themselves, including landing. Is this really true, or are there limits to what these systems can handle, such as high-crosswind landings? Thanks, Mark From hrose-saa@ckdhr.com Fri Mar 23 17:40:08 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:08 From: Wolfgang Keller Subject: Wing vs. tail-mounted engines? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: [Posted via] Interactive Networx NNTP-Posting-Host: ip128.frankfurt61.pub-ip.de.psi.net Hello, as a passenger, I've always preferred aircraft with tail-mounted engines (German BA's F100, for example) over those with wing-mounted engines like the 737 - because they are usually less noisy, because I felt a lot more safe with those burning chambers far behind me, away from the ground and from the fuel tanks (not that flying makes me frightened) and... [tomato-shield on] ...because they look so much more elegant. :-) [tomato-shield off] As an engineer who had also some classes about aerodynamics, structural and engine design at university, I always thought that the relevant tradeoff between those two options is basically aerodynamics vs. structural weight. Wing-mounted engines should result in a lower bending moment on the wing and the hull (but they need longer and heavier landing gear) while tail-mounted engines should result in 'cleaner' wing aerodynamics (and possibly a smaller wing for the same takeoff weight), thus less drag. But the numbers I have seen, for example, for the Fokker F100 and the Fairchild-Dornier 928 don't support this at all. In fact the 928 seems to be even a bit heavier (empty weight) for nearly the same payload (but less range, maybe due to more efficient engines). Am I missing something here or are my numbers simply incorrect? 928: empty weight 25202 kg F100: empty weight 24375 kg It seems that today all manufacturers prefer wing-mounted engines over tail-mounted ones for new designs, in fact the Embraer 145 seems to be the largest new design (in the 'west') for an airliner with tail-mounted engines in the last decades - Boeing 717 and MD 90 are just 'evolutions' of an existing design, the Fokker F70/100 as well, the CRJ 50 is a derivative of a business jet, so all these don't really count. Some time ago, the situation was quite different, with the 727, DC 9 and VC 10 etc. So here's (finally :-) the question: What are the actual design tradeoffs today and how did the situation evolve over the past decades to favor wing-mounted engines that much? What would be the impact of, for example, drastically increased fuel prices and/or significantly more strict noise regulations (=> engines with bypass ratio >>10)? Regards, -- Wolfgang Keller Zu Risiken und Nebenwirkungen von Junkmail lesen Sie de.admin.net-abuse.mail und fragen sie Ihren Postmaster oder Provider From hrose-saa@ckdhr.com Fri Mar 23 17:40:09 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:09 From: johnmcgrew@aol.com (JohnMcGrew) Subject: Re: Aircraft Life References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Session Scheduler Organization: AOL http://www.aol.com In article , James Robinson writes: >While I can understand the need for overhauls of worn mechanical >components, and requalifying avionics, I know less about the need to >replace structural pieces and fuselage parts. I don't see as great a >need there. I am curious if this is just urban legend, or if this >suggestion is truly the case. Can anyone provide some insight? Structural components have a limited life too, usually defined by either flight cycles or total flight hours. Every flight stresses the structure, and like with bending any piece of metal, there is a limited number of times you can do that before it will weaken and break. Such components must be replaced long before this is likely. The question for the owners is the economics of replacing certain parts of the structure; will the revenues gained by extending a plane's life justify such costs. John From hrose-saa@ckdhr.com Fri Mar 23 17:40:10 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:10 From: Vineet Subject: A-300 Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: Technische Universitaet Darmstadt NNTP-Posting-Host: ewald-pc.wk.maschinenbau.tu-darmstadt.de Hi, I would like to request for help regarding surface co-ordinates of Airbus A-300. Does any one in this forum possess these and would be able to give a copy? Or pointers to other useful links will also be great. thank you. vineet From hrose-saa@ckdhr.com Fri Mar 23 17:40:11 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:11 From: Lukas Lusser Subject: Re: IL96M References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 25 May 2000 13:10:02 +0100, lusser.euro.unibas.ch Organization: Europainstitut Basel Karl Swartz schrieb: > > I know very little about Russian aircraft, so please forgive me if I ask > > a basic question, what and how do you tell the difference between a > > IL-96 and a IL-96M? > The Il-96-300 has Soloviev PS-90A engines and a 240,000 kb MGTOW. > Il-96M has Pratt and Whitney PW2337 engines with MGTOW increased to > 270,000 kg. The Il-96T is a freighter version of the Il-96M, with > higher-thrust PW2340 engines but the same MGTOW. I don't think there > is just an Il-96, with no suffix. Hi everybody, there is also a difference in dimensions between the Il-96-300 and the Il-96M/T. While the "basic" Il-96-300 has a fuselage length of 55 metres, the stretched M and T measure 63.9 metres. The difference is as obvious to see as the difference between a classic B747 and a B747SP (though these the are still slightly larger, of course). To compare for yourself, see http://www.bird.ch/russians/ then go to the pages on the Il-96. You'll find pictures of various -300s as well as an image each of an M and a T prototype. Lukas Lusser editor, jetstream aviation magazine at http://www.jetstream.ch/ From hrose-saa@ckdhr.com Fri Mar 23 17:40:12 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 23 Mar 2001 17:40:12 From: robinjohnson@bigfoot.com (Robin Johnson) Subject: Long-distance direct flights Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 7 May 2000 13:11:23 +1000, 068.0105.hob.iprimus.net.au X-Newsreader: Forte Agent 1.5/32.451 Organization: North Antarctica NNTP-Posting-Host: 068.0105.hob.iprimus.net.au Reply-To: robinjohnson@bigfoot.com Another thread has been discussing the A3XX size of aircraft, the trend to smaller aircraft on trunk routes and for more hub-busting routes. I have noticed in Europe, where there seems to be a much higher proportion of charter flights, the trend has gone further. Some years ago I took a scheduled flight from London to Orlando. On that particular day, mine was the only scheduled arrival from Europe, but there were many charter flights from various smaller cities, including Newcastle, Glasgow, Birmingham, East Midlands, Cardiff and several different German cities, and so on. These flights are obviously in accordance with traffic demand, and generally operate full. The great concentration of tourist attractions in Central Florida is the cause. Nowadays the main charter carriers are investing in longer-range aircraft, but at the time many of these flights staged through Bangor, Maine. This airport has specialised in transit traffic requiring Customs/Immigration clearance. Holiday charters have now started from Britain (Gatwick, Luton and Manchester) to Australia and New Zealand. These flights (in 767-300s at the moment) usually make two en-route stops (e.g. Bahrain and Singapore) and operate to several Australian airports, some of which have to provide Customs/Immigration clearance not otherwise required (Coolangatta, Hamilton Island, Alice Springs) on a low-frequency basis. They do not carry mail or cargo. I'd suggest to those people who think non-stop flights between any city pair on the globe are coming that the charter flights, which by definition give a good measure of demand, are a good indication that this will not happen. If there is enough traffic, there will eventually be flights - but factoring into the equation are problems like the time passengers will sit in the one seat, aircrew duty hours, duplication of government facilities, and the economic payload/range characteristics of various aircraft types as they become available. The longest flight stages at present operated by scheduled airlines run about 15 hours, at which range payload is limited. Where practicable, aircraft configurations biased towards premium fares are used. This will probably still be true when 18-hour stages start, if they do, in a few years. London-Perth might be one such, or New York-Singapore. Aircrew rest positions away from the main deck are being on the drawing boards - they already exist on some 747-400s. I find it hard to believe there will ever be sufficient traffic at economic fares to justify scheduled nonstop flights on more than a small number of these very-long-haul routes. There will continue to be a concentration on hub cities for very large aircraft, and flights by smaller aircraft will cover pairs of smaller cities. If anyone has information on actual journey origin/destinations over time, as opposed to sector traffic, this may throw some light on the demand side. After all, some years ago when there were no nonstop flights from (say) Charlotte to Europe, passengers must have taken less direct routes. On a recent trip on this route, most of the passengers were still connecting at one or both ends. Robin Johnson From hrose-saa@ckdhr.com Fri Mar 23 17:40:13 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 23 Mar 2001 17:40:13 From: optcamel@ix.netcom.com (Howard and Kelly Lute) Subject: Re: Aircraft Life References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: MicroPlanet Gravity v2.12 Organization: Optimum Camel Companies, Ltd. NNTP-Posting-Host: cf.df.a8.51 In article , NOSPAM@ERIE.NET says... > When discussing old aircraft, such as 747s or DC-9s built in the '60s or > early '70s, I've heard a number of people say that there are practically > no original components on them. They suggest that practically everything > would have been changed during maintenance over the years, from > structural components to machinery and avionics. > While I can understand the need for overhauls of worn mechanical > components, and requalifying avionics, I know less about the need to > replace structural pieces and fuselage parts. I don't see as great a > need there. I am curious if this is just urban legend, or if this > suggestion is truly the case. Can anyone provide some insight? Not an answer just more speculation, I have a library full of books that discuss this and other long term maintenance issues on aircraft and it seems that some percentage of the basic airframe IS changed over time but certainly NOT a high percentage of the airframe itself. Certainly engines are routinely swapped out, interior equipment is upgraded and electrical/electronic equipment is upgraded or R&R'd routinely but I would venture a guess that a large percentage (75-90%) of the aircraft is the same now as when she first crossed V2. Maybe a Boeing, MD or other repair/maint. person could help us here... friend, Lute -- Howard and Kelly Lute He: Electronics Instructor, Terrible Mechanic, Worse Plumber She: Patient eBay: kell Rating: 523 402 Marina Blvd. Suisun City, CA 94585 Lute's Pirate Radio Page: http://pw1.netcom.com/~optcamel/camel2.html More Comfortable Stylish Clothing: http://www.optcamel.com/kellyscloset.jpg Check Here Before you Buy ANYTHING: http://www.epinons.com His Pirate Radio Site: http://pw1.netcom.com/~optcamel/camel2.html Try ePinions before you buy: http://www.epinions.com From hrose-saa@ckdhr.com Tue Mar 27 16:05:13 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:13 From: Malcolm Weir Subject: Re: Aircraft design question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Forte Agent 1.8/32.548 Organization: Little to None NNTP-Posting-Host: !c1^Z1k-Y'YS:jq@W`9"H$gAn (Encoded at Airnews!) On 23 Mar 2001 17:40:04 , "John R Weiss" caused to appear as if it was written: >"Matthew Willshee" wrote in message >news:airliners.2001.42@ditka.Chicago.COM... >> Dafydd ab Hugh wrote in message >> news:airliners.2001.3@ditka.Chicago.COM... > >> > There must be something out there; engineers build airplanes with >> > passenger windows, so somebody knows how to design them! > >> The windows will probably be glass, which is a ceramic. > >Aircraft windshields are often made of laminates of acrylic and glass. >Curved sections, like fighter canopies, are made of acrylic alone. > >I believe windows on deep submersibles have been made of quartz. Actually, no. Deep submersibles (e.g. the Trieste, which hold the record for the deepest dive ever, and one that won't be exceeded without a shovel!) use plexiglass. The reason is as another poster stated: ceramics don't have a failure limit, they have a probability function. Plexiglass, by contrast, "cold flows" under enormous pressure. So undetectable flaws "heal" rather than rupture. But the bottom line is that Piccard (the man who deisgned and built the Triest) used plexiglass for that vessel, and the problems facing submersible are different: huge pressure, low hear. Aircraft face high temperatures, and trivial pressure (14.7psi vs ~90,000psi, IIRC, at 20,000 feet below sea level). Malc. From hrose-saa@ckdhr.com Tue Mar 27 16:05:14 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:14 From: "ME Incorporated" Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 26 Mar 2001 15:06:14 -0600, 216-119-131-253.ipset11.wt.net X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: World Trade Network, Inc. (WT.net) NNTP-Posting-Host: 216-119-131-253.ipset11.wt.net "Wolfgang Keller" wrote in message > What are the actual design tradeoffs today and how did the situation > evolve over the past decades to favor wing-mounted engines that much? What > would be the impact of, for example, drastically increased fuel prices > and/or significantly more strict noise regulations (=> engines with bypass > ratio >>10)? I'm no expert, but the biggest concern is saleablity. In other words, if all things are equal, what's the x factor in selling an Airbus or a Boeing (or a McDonnell Douglas, before the merger...) The DC10 was orignally thought of as a twin engine. Then a four engine. The three engine was perfect, given it's requirement. But how to mount it? And of course, Lockheed got into it too, and designed the Tristar. While they both have tail mounted engines, they did their differently. DC10 way up on a "banjo" fitting, the largest forged piece at the time, and the L10 in the fuselage using a duct. In BOTH cases, it was a harder sell than a twin or four engine, because of the mainenance of the third, tail mounted engine. In a 717/DC9/MD80 or a 727, this was a little be easier, because they weren't as high off the ground. But in a DC10, well, this was a BIG deal. And so, with more powerful engines, and the complaints/requests of big clients such as American, United, etc, these tail mounted engines are becoming a non desired design. Hence, the design of the 777. Very much an airplane designed by and with the airlines, and not just the plane makers designing around a spec. You can bet that Boeing wanted more engines, and maybe in the tail, but because of that maintenance thing, two is cheaper, and wing mounted cheaper still. Anyway. It's economics. The airlines would rather have simpler maintenance requirements than the DC10/747s require, which translates into less money spent. Bean counting anyone? 8^) Two underwings are simpler than 4, and way simpler than any tail buried DC10. BTW, from an engineering standpoint, the wing is easier to build/design when hanging engines off of it, instead of "clean" like the 727. At least, that's what I've read/heard/figured out. I'm sure someone's gonna boot me in the head now... Go on then! 8^) From hrose-saa@ckdhr.com Tue Mar 27 16:05:15 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:15 From: {$usenet$}@apple-juice.co.uk (Daniele Procida) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news11-gui.server.ntli.net 985617457 62.252.54.196 (Mon, 26 Mar 2001 15:37:37 BST) Organization: Apple Juice, Cardiff - Macintosh support and sales NNTP-Posting-Host: 62.252.54.196 Wolfgang Keller wrote: > as a passenger, I've always preferred aircraft with tail-mounted engines > (German BA's F100, for example) over those with wing-mounted engines like > the 737 - because they are usually less noisy, because I felt a lot more > safe with those burning chambers far behind me, away from the ground and > from the fuel tanks (not that flying makes me frightened) As someone who is scared out of his wits by aeroplanes, I much prefer MD-80s and the like, because the sight of those enormous heavy engines making those delicate wings bend up and down in that terrifying fashion is something I can really do without. At least on a MD-80 I don't spend the entire flight checking to see if the wings are going fall off. Instead I worry about an uncontained blade failure ripping into the fuselage or destroying the tailplane. Daniele -- Apple Juice Macintosh service, support & sales Cardiff 029 2041 0050 drink.different@apple-juice.co.uk www.apple-juice.co.uk From hrose-saa@ckdhr.com Tue Mar 27 16:05:16 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 27 Mar 2001 16:05:16 From: Janne Salonen Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: nntp.hut.fi 985606820 26824 130.233.224.22 (26 Mar 2001 11:40:20 GMT) Organization: Helsinki University of Technology NNTP-Posting-Host: leka.hut.fi On 23 Mar 2001, Robin Johnson wrote: > Another thread has been discussing the A3XX size of aircraft, the > trend to smaller aircraft on trunk routes and for more hub-busting > routes. > I find it hard to believe there will ever be sufficient traffic at > economic fares to justify scheduled nonstop flights on more than a > small number of these very-long-haul routes. There will continue to > be a concentration on hub cities for very large aircraft, and flights > by smaller aircraft will cover pairs of smaller cities. > If anyone has information on actual journey origin/destinations over > time, as opposed to sector traffic, this may throw some light on the > demand side. After all, some years ago when there were no nonstop > flights from (say) Charlotte to Europe, passengers must have taken > less direct routes. On a recent trip on this route, most of the > passengers were still connecting at one or both ends. Your post does not seem to have elicited much response, but I'll try my hand. Boeing's thesis is that A380-sized aircraft do not have sufficient market, relying on megahubs and connecting feeder flights, and that direct traffic between city pairs using smaller average aircraft size (B777, A330-A340) is going to win market share. Charter traffic really is for package tours and the like, seldom for regular traffic, although more frequently unsold seats are being offered on flight-only basis. Regular traffic requires sufficient demand to fill planes several times a week, scheduled destinations with only one or two departures a week are seldom commercially viable. For example Finnair has canceled such destinations (Osaka, San Francisco, Toronto). People flying from San Francisco to Helsinki aren't going to wait around many days for the next scheduled direct flight, they take the first one to Europe and change. So, up to a point, Boeing can be right with its thesis of traffic moving away from trunk routes, but on the other hand these will also remain, because the traffic from, say, Helsinki to Denver will always be too sparse to warrant a direct connection. On intercontinental or long transcontinental routes, smaller than 250-300 seat aircraft are unlikely to be competitive, and demand insufficient to fill such aircraft several times a week is likely to use trunk lines and interconnecting feeders. Another important factor, especially on destinations between Europe and Asia, and I suspect between the US and Asia as well, is freight traffic, which generates a fair bit of revenue for the airlines operating these routes. A big part of the reason why Asian carriers have been ordering A380's is the much-increased cargo capacity it offers compared with any other airliner, and there is also interest in cargo versions of the aircraft. And a cargo version of Boeing's 747X seems to be the closest to market. It seems that A380s will have a market, although it might take some while until Airbus sells enough planes to cover development costs. Perhaps it wouldn't be surprising if Boeing at some point tries to leapfrog A380 and offers a still bigger plane. One interesting alternative could in time be provided by airships, once they can establish themselves. They should be able to offer much more comfortable but slower flights than turbojets, and be more fuel economical. Janne Salonen Helsinki, Finland From hrose-saa@ckdhr.com Tue Mar 27 16:05:17 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:17 From: leodmo@earthlink.net Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newsread1.prod.itd.earthlink.net 985589393 158.252.249.143 (Sun, 25 Mar 2001 22:49:53 PST) X-Newsreader: News Rover 6.1.0 (http://www.NewsRover.com) Organization: EarthLink Inc. -- http://www.EarthLink.net NNTP-Posting-Host: 158.252.249.143 "Wolfgang Keller" wrote in message > What are the actual design tradeoffs today and how did the situation > evolve over the past decades to favor wing-mounted engines that much? What > would be the impact of, for example, drastically increased fuel prices > and/or significantly more strict noise regulations (=> engines with bypass > ratio >>10)? I haven't read any articles addressing the issues of weight, balance, and aerodynamics. However, safety might be a major reason for "below the wing" mounted engines. When an engine is in serious trouble in the rear of the AC, it can take out the other engines or critical hydraulic systems. (DC10 at Sioux City, IO) If an engine is mounted in a wing, then the engine can damage the wing or fuel tanks. When mounted below the wing, the engine parts (catastropic failures) have a smaller probability of hitting critical wing parts or the fuel tanks. Also, external mount allows the engine to actualy depart the AC leaving the AC a chance to fly. Although the following paragraph may not relate to modern jet design, you may find it interesting. Remember the old Boeing Stratocrusers (passenger form of the B29-B50). An engine could (and did) fail in such a way that the entire engine would twist out of the wing and depart the AC. This added so much drag to the AC that it could not fly with three engines at full power. At least 4 accidents were directly attributed to the complete physical loss of the engine and there were several other near misses where the pilots could make a powered glide to an airstrip. Dennis From hrose-saa@ckdhr.com Tue Mar 27 16:05:18 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,misc.transport.air-industry Date: 27 Mar 2001 16:05:18 From: gbeaman@pei.sympatico.ca (Gord Beaman) Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: sapphire.mtt.net 985542976 142.176.111.56 (Sun, 25 Mar 2001 13:56:16 AST) X-Newsreader: Forte Free Agent 1.21/32.243 Organization: ISLAND TEL Reply-To: ve1eo@rac.ca NNTP-Posting-Host: 142.176.111.56 don@news.daedalus.co.nz (Don Stokes) wrote: >Malcolm Weir wrote: >>All indications are that the thing was flyable in the sense that it was >>above the control speeds for its configuration. It lacked the speed to >>climb, though. > >Nope. For most of the flight, one of the port side engines was >producing some power, albeit well below capacity due to damage. When >that engine finally failed, the aircraft no longer had suffient power, >at which point the aircraft stalled, yawing toward the port side and >rolling over, and crashed. >The crew did very well to get the plane on an emergency approach to Le >Bourget on only 2 and a bit engines, but with the loss of the bit, the >physics of the situation was against them. Yes and especially so considering the fact that they couldn't get the gear up...not too many a/c will fly with a critical engine out at V1 when you cannot get the gear up. Then, to lose the 'other' engine on that side sealed their fate. From hrose-saa@ckdhr.com Tue Mar 27 16:05:19 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:19 From: bbarksdl@aol.com (BBarksdl) Subject: How Important Is Cross-section Shape Of Wing? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: AOL http://www.aol.com In the April issue of Discover magazine, Robert Kunzig challanges the textbook explanation of the principles of flight. I have always felt the books were wrong on this when they say that the shape of the wing invokes Bernoulli's Principle to provide the lift required. Kunzig refutes the role of Bernoulli's Principle. He says that planes fly by pushing air down, getting lift from the equal and opposite reaction that pushes the plane up. I'm trying to reconcile that with my own thoughts on the subject - that the forces that cause an airplane to fly are essentially the same as those that cause a kite to fly. Either way you look at it, the shape of the wing is not the main element. Otherwise, how could a plane fly upside-down? As an old barnstormer was reported to have said, "Give me enough power, and I'll fly a barn door." From hrose-saa@ckdhr.com Tue Mar 27 16:05:20 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:20 From: glpilotsrv@aol.com (GLPILOTSRV) Subject: Re: Deice References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Session Scheduler Organization: AOL http://www.aol.com David Pinella wrote in message news:airliners.2001.6@ditka.Chicago.COM... > I was on a Canadair RJ yesterday. I think this is the first time that I > have been on a plane that was deiced. I have a question. How much does > deicing cost for a plane like this? A 747? How many gallons? Is it > recycled? It looked like they used a pink spray and then a green spray. > I assume the red is a deice and the green is an anti ice, like ethelyne > glycol. It stuck really nice to the wing, very pretty. What was the red? There are several types of de-ice and anti-icing fluids. What you saw was Type 1 fluid being applied, followed by an application of Type 4 fluid. Type 1 is the reddish orange fluid It is a very thin fluid that is heated and applied to de-ice the aircraft. To prevent ice from reforming, Type 4 fluid is applied. Type 4 is the emerald green fluid that is not heated. Type 4 is a thicker fluid and can be used on aircraft that have a rotate speed greater that 80 to 100 knots. Aircraft with slower rotate speeds would not generate the necessary energy to shear and eliminate the fluid from the aircraft prior to take-off. The cost of de-icing an aircraft varies greatly. The variances include the cost of the fluid, the weather conditions, and the pilot's request (wings and stab only or entire aircraft). I have been charged as little as $250.00 US dollars in Kansas to a whopping $10,000 CA dollars in Montreal. G. Lee From hrose-saa@ckdhr.com Tue Mar 27 16:05:21 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:21 From: ppowondra@aol.com (PPowondra) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: AOL http://www.aol.com >Subject: Wing vs. tail-mounted engines? >From: Wolfgang Keller >I felt a lot more >safe with those burning chambers far behind me, away from the ground and >from the fuel tanks Wolfgang, Wouldn't there be some concern for how the fuel for those "burning chambers" gets back there from the wing or centerbody tanks? I seem to recall that those fuel lines approximate the size of an adult arm, running along the length of the fuselage. Certainly a consideration (among others, I'm sure) in new airliner designs. The rear-mounted engine layout apparently has been relegated to the RJ's and bizjets. I wonder how the CG concerns impact the tail vs. wing designs for large a/c... Best, Paul From hrose-saa@ckdhr.com Tue Mar 27 16:05:22 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:22 From: CptKrell@aol.com Subject: Re: Wing vs. tail-mounted engines? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: multipart/alternative; boundary="part1_bd.cc58dfc.27eded68_boundary" > What are the actual design tradeoffs today and how did the situation > evolve over the past decades to favor wing-mounted engines that much? What > would be the impact of, for example, drastically increased fuel prices > and/or significantly more strict noise regulations (=> engines with bypass > ratio >>10)? Well, wing mounted engines are a great deal easier to inspect, turn wrenches on, exchange, etc so lower maint. costs may play a role in design decisions. One would think that would also would translate into higher maint. costs resulting from FOD because of intake proximity to the ground, however main gear kick-up of debris into higher mounted rear engines may make this statistic a wash. Just further speculation on my point, but if you're really interested I should think more than one thesis is avail on-line or in the myriad of aircraft design publications on the shelves................Jack (Detroit) DTW / YIP From hrose-saa@ckdhr.com Tue Mar 27 16:05:23 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 27 Mar 2001 16:05:23 From: Roger Chung-Wee Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: nnrp3.clara.net 985431425 213.123.119.77 (Sat, 24 Mar 2001 10:57:05 GMT) X-Newsreader: Forte Agent 1.8/32.548 NNTP-Posting-Host: 213.123.119.77 On 23 Mar 2001 17:40:12 , robinjohnson@bigfoot.com (Robin Johnson) wrote: >Holiday charters have now started from Britain (Gatwick, Luton and >Manchester) to Australia and New Zealand. These flights (in 767-300s >at the moment) usually make two en-route stops (e.g. Bahrain and >Singapore) and operate to several Australian airports, some of which >have to provide Customs/Immigration clearance not otherwise required >(Coolangatta, Hamilton Island, Alice Springs) on a low-frequency >basis. They do not carry mail or cargo. Note that the charters from the UK to Australia and New Zealand by Airtours and Britannia have been axed. It seems as if scheduled competition was the main reason. >I'd suggest to those people who think non-stop flights between any >city pair on the globe are coming that the charter flights, which by >definition give a good measure of demand, are a good indication that >this will not happen. If there is enough traffic, there will >eventually be flights - but factoring into the equation are problems >like the time passengers will sit in the one seat, aircrew duty hours, >duplication of government facilities, and the economic payload/range >characteristics of various aircraft types as they become available. >The longest flight stages at present operated by scheduled airlines >run about 15 hours, at which range payload is limited. Where >practicable, aircraft configurations biased towards premium fares are >used. This will probably still be true when 18-hour stages start, if >they do, in a few years. London-Perth might be one such, or New >York-Singapore. Aircrew rest positions away from the main deck are >being on the drawing boards - they already exist on some 747-400s. The evidence is that people are not really keen on charter flights lasting more than about nine hours. The main long-haul markets are from western Europe, particularly Germany and the UK, to holiday destinations, especially the Caribbean and Florida, where there is plenty of sunshine and other attractions, so why fly further to the Far East or Hawaii. I think that the long-haul charter market is now mature and, due to cost reasons, will not expand much. Airtours, for instance, finds it more profitable to fly from the UK to Palma de Mallorca than Barbados. -- Visit Caribbean Aviation: http://www.caribbeanaviation.com/ From hrose-saa@ckdhr.com Tue Mar 27 16:05:24 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:24 From: "matt weber" Subject: Re: Long-distance direct flights Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="us-ascii"; format=flowed >Holiday charters have now started from Britain (Gatwick, Luton and >Manchester) to Australia and New Zealand. These flights (in 767-300s >at the moment) usually make two en-route stops (e.g. Bahrain and >Singapore) and operate to several Australian airports, some of which >have to provide Customs/Immigration clearance not otherwise required >(Coolangatta, Hamilton Island, Alice Springs) on a low-frequency >basis. They do not carry mail or cargo. Actually I think reltaively few actually go through Singapore or Bahrain, both are relatively costly for charter operators, and if all you are doing is hauling people, cost is what counts.. I know the last one I actually tracked (a Britannia 767-300 was leaving just before I was from MEL for LGW) was routing through some regional airport in Indonesia (it took me a while to figure out where it actually was, because it was a code I had never seen before)..., and Abu Dhabi. The attraction of both places was very low fuel and ground handling costs. >The longest flight stages at present operated by scheduled airlines >run about 15 hours, at which range payload is limited. Where >practicable, aircraft configurations biased towards premium fares are >used. This will probably still be true when 18-hour stages start, if >they do, in a few years. London-Perth might be one such, or New >York-Singapore. Aircrew rest positions away from the main deck are >being on the drawing boards - they already exist on some 747-400s. >I find it hard to believe there will ever be sufficient traffic at >economic fares to justify scheduled nonstop flights on more than a >small number of these very-long-haul routes. There will continue to >be a concentration on hub cities for very large aircraft, and flights >by smaller aircraft will cover pairs of smaller cities. I think there is already clear evidence of that from other sources. The Mission requirement from SQ for the SIN-LAX run is 200 pax. However, if you look, there are about dozen routes and carriers that can get you from SIN to LAX by stopping at various points like Seoul, Hong Kong, Osaka, Manilla,Narita. On a daily basis, the 200 seats SQ plans for on the non-stop is very small portion of the available lift between these points. The 200 pax operation is going to have horrible ASM costs, so the load will have to heavily loaded toward the premium cabins, the question is can enough people justify the difference in fares between a SIN-NRT-LAX versus say a SIN-LAX non-stop routing to justify a fare that is enough higher to cover the costs? NRT is essentiallly on the SIN-LAX great circle, so in theory a stop in NRT might add as little as 2 hours to the total travel time, and unless the A340-500 performs considerable faster then the A340-200/300, a good part of that 2 hours may be lost due to the 747-400's higher cruise speeds and ability to fly at more attractive altitudes... Matt Weber From hrose-saa@ckdhr.com Tue Mar 27 16:05:25 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:25 From: "matt weber" Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit ----- Original Message ----- From: "Malcolm Weir" To: Sent: Wednesday, March 21, 2001 6:33 PM Subject: Re: Air France Concorde crashes after departing Paris CDG > On 16 Mar 2001 05:56:29 , Wolfgang Keller caused to appear > as if it was written: > > [ Snip ] > > >Question to the more competent people here: How 'flyable' would a Concorde > >with two failed engines (on one side) be. I thought I've read somewhere > >that during the original trials, the manufacturers had to make the > >experience that the loss of one engine already made the aircraft yaw quite > >lot. So with both engines on one side lost, I guess there might have been > >problems with the other two no longer getting enough air in the intakes? > > All indications are that the thing was flyable in the sense that it was > above the control speeds for its configuration. It lacked the speed to > climb, though. Flyable only in a very narrow sense of the word. Concorde is a strange airliner in that minimum drag at MGTOW on most aircraft is pretty close to V2, on Concorde it is at 415kt. The full thrust of 2 engines on Concorde is roughly equal to drag at 275kt. Below 275kt, drag exceeds thrust, consequently flight at speeds below 275kt on 2 engines is a black hole in the flight envelope. If you get into it, unless you can somehow get the speed above 275kt, or get another engine going, the outcome will be fatal. You cannot remain in the air for very long.. At low altitude, it is in fact a death trap. The emergency operations procedures recognize this, in that in the event of an engine failure, the priority on departure changes from climb rate to air speed, to get beyond the 275kt problem ASAP. At speeds below 275kt, the drag slows the aircraft, forcing the pilot to raise the angle of attack to maintain lift, which creates still more drag, slowing the aircraft still further until it finally falls out of the air... From hrose-saa@ckdhr.com Tue Mar 27 16:05:26 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 27 Mar 2001 16:05:26 From: "matt weber" Subject: Re: Concorde tyres References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit ----- Original Message ----- From: "Stephen H. Westin" > > > 2. One newspaper reported that experts from the Goodyear Co. had > > flown in from the US to assist the investigation. Presumably > > this is because Goodyear supplied the tyres for Concorde? > > Or perhaps they have some special expertise that would be useful, or a > unique testing facility. > The tires on the AF Concorde are made by Goodyear, BA uses Dunlop tires... From hrose-saa@ckdhr.com Sat Mar 31 16:43:02 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:02 From: FilipPC.DeVos@rug.ac.be (Filip De Vos) Subject: Re: Air France Concorde crashes after departing Paris CDG References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: TIN [version 1.2 PL2] Organization: University of Ghent, Belgium NNTP-Posting-Host: eduserv1.rug.ac.be matt weber (mattheww50@home.com) wrote: : Flyable only in a very narrow sense of the word. Concorde is a strange : airliner in that minimum drag at MGTOW on most aircraft is pretty close to : V2, on Concorde it is at 415kt. The full thrust of 2 engines on Concorde is : roughly equal to drag at 275kt. Below 275kt, drag exceeds thrust, : consequently flight at speeds below 275kt on 2 engines is a black hole in Part of that drag is the rudder, deflected to compensate for the assymetric thrust. So my question is, is it possible to make a climbing turn at a lower speed than 275kt? (turning towards the dead engines) : the flight envelope. If you get into it, unless you can somehow get the : speed above 275kt, or get another engine going, the outcome will be fatal. : You cannot remain in the air for very long.. At low altitude, it is in : fact a death trap. -- "Who needs credibility around | Filip De Vos here?" -- T. L. Elifritz | FilipPC.DeVos@rug.ac.be From hrose-saa@ckdhr.com Sat Mar 31 16:43:03 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:03 From: johnmcgrew@aol.com (JohnMcGrew) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Session Scheduler Organization: AOL http://www.aol.com In article , Wolfgang Keller writes: >What are the actual design tradeoffs today and how did the situation >evolve over the past decades to favor wing-mounted engines that much? What >would be the impact of, for example, drastically increased fuel prices >and/or significantly more strict noise regulations (=> engines with bypass >ratio >>10)? Weight: Putting engines in the back requires extra load carrying structure, both for the thrust and the weight of the engine itself. On the other hand, little extra structure is required for the wing mounted engine since there's structure already there; the wing is mostly structure. Advantage: Wing Mount. Noise: Clearly, advantage rear, except perhaps for those sitting in the back. Advantage: Rear Mount. Maintenance: Most maintenance on wing-mounted engines can be performed at ground level without lifts or scaffolding. Significant appeal to maintenance staffs. Advantage: Wing. Engine-Out Performance: Single-engine control is much better with rear-mounted engines over wing, simply because thrust is far less asymmetrical because the engines are so much closer towards the center. Advantage: Rear Aerodynamics: Rear-mount allows for a cleaner wing design, and less conflicts with airflow and mechanics for slats and flaps. Advantage: Rear. However, most rear engine configurations necessitate a T-Tail configuration for the horizontal stabilizer, which requires extra weight for structure at the top of the vertical stabilizer, as opposed to conventional horizontal stabilizers attached to existing structure at the end of the fuselage. CG Considerations: There are differences in handling and stall characteristics that tend to favor wing with the engine weight near the CG vs the increased moment as a result of having a longer nose and all that weight in the rear. However, advanced control systems and pilot training tend to negate these differences. Ground Handling: Many rear-mounted designs allow the use of reverse thrust for backing up the aircraft with limited danger of FOD ingestation, thus eliminating the need for a push-back at the gate. This is appealing to airlines as it means that less ground support required. Advantage: Rear. That's all I can think of at the moment. Personally, as a passenger, I prefer the MD-80 to the 737, mostly because of less noise, the 2x3 seating, and the 737 is "bumpier". But the reality is that what really determines what plane you will be flying is the economics. John From hrose-saa@ckdhr.com Sat Mar 31 16:43:04 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:04 From: johnmcgrew@aol.com (JohnMcGrew) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Newsreader: Session Scheduler Organization: AOL http://www.aol.com In article , {$usenet$}@apple-juice.co.uk (Daniele Procida) writes: >As someone who is scared out of his wits by aeroplanes, I much prefer >MD-80s and the like, because the sight of those enormous heavy engines >making those delicate wings bend up and down in that terrifying fashion >is something I can really do without. At least on a MD-80 I don't spend >the entire flight checking to see if the wings are going fall off. Actually, having the weight of the engines carried elsewhere on the airframe puts more of the load on the wing spar, which is what causes the bending you seem concerned about. On the other hand, on wing mounted engines, the weight is carried directly by the wing as opposed to the spar. John From hrose-saa@ckdhr.com Sat Mar 31 16:43:05 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:05 From: "Ken Ishiguro" Subject: Re: How Important Is Cross-section Shape Of Wing? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newsread2.prod.itd.earthlink.net 985920964 209.179.239.165 (Thu, 29 Mar 2001 18:56:04 PST) X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: EarthLink Inc. -- http://www.EarthLink.net NNTP-Posting-Host: 209.179.239.165 > Either way you look at it, the shape of the wing is not the main element. > Otherwise, how could a plane fly upside-down? Planes designed for sustained inverted flight have symmetrical or nearly symmetrical airfoil cross sections. You will note a plane flying inverted is nose-up...this is to give the wing a positive angle of attack. Also, the vertical component of thrust is a big contributor, too. If airflow over the top of the wing were unimportant, then subsonic transport aircraft could fly faster than the usual mach 0.85 . The limiting factor is when the airflow over the top of the wing accelerates and becomes supersonic, lift goes away. This wouldn't be true if the top of the wing was not a factor. (BTW, a "supercritical airfoil" is one designed to allow supersonic flow over the top of the airfoil). A thin layer of frost on the top of the wing can drastically reduce lift. This too, would not happen if airflow over the top of the wing didn't matter. >As an old barnstormer was > reported to have said, "Give me enough power, and I'll fly a barn door." > You're confusing two modes of flight...flight due to wing lift (sailplanes as the ultimate example), and flight due to brute thrust (the Space Shuttle). Ken Ishiguro From hrose-saa@ckdhr.com Sat Mar 31 16:43:06 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:06 From: "Ken Ishiguro" Subject: Re: Aircraft design question References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newsread2.prod.itd.earthlink.net 985920059 209.179.240.81 (Thu, 29 Mar 2001 18:40:59 PST) X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: EarthLink Inc. -- http://www.EarthLink.net NNTP-Posting-Host: 209.179.240.81 "Dafydd ab Hugh" wrote in message news:airliners.2001.3@ditka.Chicago.COM... > Dear aerospace engineers; > > My wife is an aerospace engineering student at Cal Poly Pomona, and > for her senior thesis, she is supposed to design a passenger window > for a future single-stage-to-orbit (SSTO) vehicle Part of engineering is capturing and meeting requirements in cost effective or unique ways. Why is there a requirement for a window? Presumably so the passenger can see out, and also so people don't become claustrophobic. As you and others have stated, there's a lot of factors involved. ISTM that an ergonomically designed cabin and lighting will provide an illusion of spaciousness. Airframe manufacturers and airlines put a lot of effort into cabin design to accomplish this. As far as seeing out, a camera system and an in-seat LCD display with individually selectable / changeable views will meet the "see out" requirement. I don't know how your wife's prof would view this approach...but in the real world, the lowest cost, safest, or "thinking out of the box" solution wins. Boeing has proposed this for their Blended Wing design, where only a small portion of seats would be near a window. My .02 worth. Ken Ishiguro From hrose-saa@ckdhr.com Sat Mar 31 16:43:07 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:07 From: damon@halcyon.com (Damon Hill) Subject: Boeing's Sonic Cruiser Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Organization: http://extra.newsguy.com NNTP-Posting-Host: news.newsdawg.com Will it fly? Will the airlines buy? I hope so! Commercial aircraft design has been SO boring for the past couple of decades. How fast WILL it go? It already looks supersonic, with the right engines. http://www.boeing.com/news/feature/concept/ --Damon From hrose-saa@ckdhr.com Sat Mar 31 16:43:08 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:08 From: Ron Parsons Subject: Re: How Important Is Cross-section Shape Of Wing? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: /K49oE6QsJSzKTsr3aqEEJ4WAZ4G+z8qb41dUWWooSpuMK91pFqA7HO+1lHs+0q2/c7BFxKvTDPC!wABWWXitroTH84ZGFIL7lkZukuInBcOnBApDG9EQQOhcPooBkNpmjPz+rKMU0lDLzMcF2o8bgEZv!UC8gOnlG2MZQbA== In article , bbarksdl@aol.com (BBarksdl) wrote: >In the April issue of Discover magazine, Robert Kunzig challanges the textbook >explanation of the principles of flight. I have always felt the books were >wrong on this when they say that the shape of the wing invokes Bernoulli's >Principle to provide the lift required. Kunzig refutes the role of Bernoulli's >Principle. He says that planes fly by pushing air down, getting lift from the >equal and opposite reaction that pushes the plane up. I'm trying to reconcile >that with my own thoughts on the subject - that the forces that cause an >airplane to fly are essentially the same as those that cause a kite to fly. >Either way you look at it, the shape of the wing is not the main element. >Otherwise, how could a plane fly upside-down? As an old barnstormer was >reported to have said, "Give me enough power, and I'll fly a barn door." He is correct. Bernoulli's equations are for use in a lab situation. If you have one set of readings, they will predict another set of readings. To understand flight, apply Newton's mass/accelaration calculations. The shape or cross section of the wing has a great deal to do with reducing drag, and almost nothing to do with "lift" which is one of those bogus terms for something which doesn't exist. -- Ron From hrose-saa@ckdhr.com Sat Mar 31 16:43:09 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:09 From: John Naus Subject: Re: How Important Is Cross-section Shape Of Wing? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 29 Mar 2001 11:41:00 -0500, fn3.tfn.net NNTP-Posting-Host: fn3.tfn.net BBarksdl wrote: > In the April issue of Discover magazine, Robert Kunzig challanges the textbook > explanation of the principles of flight. I have always felt the books were > wrong on this when they say that the shape of the wing invokes Bernoulli's > Principle to provide the lift required. Kunzig refutes the role of Bernoulli's > Principle. He says that planes fly by pushing air down, getting lift from the > equal and opposite reaction that pushes the plane up. I'm trying to reconcile > that with my own thoughts on the subject - that the forces that cause an > airplane to fly are essentially the same as those that cause a kite to fly. > Either way you look at it, the shape of the wing is not the main element. > Otherwise, how could a plane fly upside-down? As an old barnstormer was > reported to have said, "Give me enough power, and I'll fly a barn door." The answer is that lift is a combination of both Bernoulli and opposite reaction forces. A good example of opposite recation playing a significant role is when the aircraft is in "ground effect". I have not seen the article myself but would be interested in hearing Kunzig's description of how a wing top vortex generator or stall gate works. If lift was only provided by air pushing down from a wing the top of the wing would be flat. Obviously, a flat wing would be cheaper to produce then a curved wing! To answer your question about flying upside-down you are correct in saying that power can be used to overcome loss of lift. If you remove the wings and add a big enough engine anything will fly (ie. a rocket). John From hrose-saa@ckdhr.com Sat Mar 31 16:43:10 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:10 From: "Nate Meier" Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news20.bellglobal.com 985839471 64.229.139.181 (Wed, 28 Mar 2001 23:17:51 EST) X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 Organization: Sympatico NNTP-Posting-Host: 64.229.139.181 "Daniele Procida" <{$usenet$}@apple-juice.co.uk> wrote in message news:airliners.2001.66@ditka.Chicago.COM... > As someone who is scared out of his wits by aeroplanes, I much prefer > MD-80s and the like, because the sight of those enormous heavy engines > making those delicate wings bend up and down in that terrifying fashion > is something I can really do without. At least on a MD-80 I don't spend > the entire flight checking to see if the wings are going fall off. Having the engines mounted under the wings actually reduces some of the load on the wing (lift force on wing - engine weight on wing). > Instead I worry about an uncontained blade failure ripping into the > fuselage or destroying the tailplane. Uncontained blade failures are fairly rare and engines (and casings) must be designed to contain any blade failures. Uncontained rotor bursts, on the other hand, are much more common than uncontained blade failures. I'd be more worried about rotor bursts since they release wayyyy more energy and a lot more flying bits. Nathan Meier From hrose-saa@ckdhr.com Sat Mar 31 16:43:11 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:11 From: Mad Monks Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: brie.direct.ca 985805055 216.66.156.45 (Wed, 28 Mar 2001 10:44:15 PST) Organization: Look Communications - http://www.look.ca X-Newsreader: Forte Agent 1.8/32.548 NNTP-Posting-Host: 216.66.156.45 Daniele Procida <{$usenet$}@apple-juice.co.uk> wrote: >As someone who is scared out of his wits by aeroplanes, I much prefer >MD-80s and the like, because the sight of those enormous heavy engines >making those delicate wings bend up and down in that terrifying fashion >is something I can really do without. At least on a MD-80 I don't spend >the entire flight checking to see if the wings are going fall off. The wing mounted engines are there because it makes for easier lengthening and shortening of the a/c. The chief engineer for the 747 pushed through the wing-mounted engine for the 737 so that the a/c could be better balanced and also lengthened (so we now have a/c as short as the 737-500 and as long as the -900). A tail-mounted engine would have limited this flexiblity. From hrose-saa@ckdhr.com Sat Mar 31 16:43:12 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:12 From: don@news.daedalus.co.nz (Don Stokes) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: raewyn.paradise.net.nz 985789039 85843 203.96.144.16 (28 Mar 2001 14:17:19 GMT) Organization: Daedalus Consulting X-Newsreader: trn 4.0-test72 (19 April 1999) NNTP-Posting-Host: 203-96-144-16.cable.paradise.net.nz Daniele Procida <{$usenet$}@apple-juice.co.uk> wrote: >As someone who is scared out of his wits by aeroplanes, I much prefer >MD-80s and the like, because the sight of those enormous heavy engines >making those delicate wings bend up and down in that terrifying fashion >is something I can really do without. At least on a MD-80 I don't spend >the entire flight checking to see if the wings are going fall off. Actually, the wing stresses are lower with the engines on the wing because the wing root is not carrying the weight of the engines as well as the fuselage. Remember that the wings carry the plane, not the other way around. Of course, the tail mounted aircraft have correspondingly stronger wing root and tail structures to deal with the higher stresses, so the chances of the wings falling off are about the same: vanishingly small. (I can't think of any case of failure of the wing box or root structure causing an accident on a post-war commercial airliner -- can anyone?) -- don From hrose-saa@ckdhr.com Sat Mar 31 16:43:13 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:13 From: leodmo@earthlink.net Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: newsread1.prod.itd.earthlink.net 985766555 158.252.249.38 (Wed, 28 Mar 2001 00:02:35 PST) Organization: EarthLink Inc. -- http://www.EarthLink.net X-Newsreader: News Rover 6.1.0 (http://www.NewsRover.com) NNTP-Posting-Host: 158.252.249.38 Those "heavy" engines have nothing to do with the wing bending up and down. Since the B47 design in the late 40s, wings have been built to flex . Keep in mind the the wings are doing most of the lifting, even though as a passenger, you might feel like the empenage is lifting the wings. Thus, the weight of an engine on a wing is weight being directly lifted by the wing on which it is attached and that weight is not affecting the wing where it attaches to the empenage. If that engine were mounted at the rear of the plane, the weight would still have to be lifted, but all of the engine weight would be present at the wing root, thus increasing the amount of bend. Be of good cheer. Wings that bend work. B52 wings can flex 16 feet at their ends. B52s have been flying since the early 50's and some are expected to be in service into the 2040s. I stood near the end of a runway at Dyess AFB (Abilene TX) and watched the entire takeoff roll. It was really interesting the wing tips move from very low (near the runway) to very high as the AC gained speed. Dennis From hrose-saa@ckdhr.com Sat Mar 31 16:43:14 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:14 From: "Robert H. Nielsen" Subject: A fascinating tidbit from Boeing Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: bgtnsc06-news.ops.worldnet.att.net 985756602 12.82.153.39 (Wed, 28 Mar 2001 05:16:42 GMT) Organization: AT&T Worldnet NNTP-Posting-Host: 12.82.153.39 Check out this link to a story about a Boeing design for a high-subsonic airliner: http://biz.yahoo.com/rf/010326/n26655542_2.html Wouldn't his give the A380 market a case of the fits! From hrose-saa@ckdhr.com Sat Mar 31 16:43:15 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 31 Mar 2001 16:43:15 From: R J Carpenter Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: UmFuZG9tSVbpp6H3UiKnSDpIz/Upl9jIGykTJlBsIYPb5nlFRrAcSm1oV10sUQJP Janne Salonen wrote: > One interesting alternative could in time be provided by airships, once > they can establish themselves. They should be able to offer much more > comfortable but slower flights than turbojets, and be more fuel > economical. IMO, anything that flies only a few thousand feet above the ground, and at low speed, is not going to succeed. Low altitude weather would be a severe problem, and flying at only a few times frequently-encountered wind velocities would make schedules unreliable. From hrose-saa@ckdhr.com Sat Mar 31 16:43:16 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 31 Mar 2001 16:43:16 From: robinjohnson@bigfoot.com (Robin Johnson) Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 28 Mar 2001 13:40:33 +1000, 202.138.58.198 Organization: North Antarctica X-Newsreader: Forte Agent 1.5/32.451 Reply-To: robinjohnson@bigfoot.com NNTP-Posting-Host: 202.138.58.198 On 27 Mar 2001 16:05:23 , Roger Chung-Wee told us: >On 23 Mar 2001 17:40:12 , robinjohnson@bigfoot.com (Robin Johnson) >wrote: > >>Holiday charters have now started from Britain (Gatwick, Luton and >>Manchester) to Australia and New Zealand. These flights (in 767-300s >>at the moment) usually make two en-route stops (e.g. Bahrain and >>Singapore) and operate to several Australian airports, some of which >>have to provide Customs/Immigration clearance not otherwise required >>(Coolangatta, Hamilton Island, Alice Springs) on a low-frequency >>basis. They do not carry mail or cargo. >Note that the charters from the UK to Australia and New Zealand by >Airtours and Britannia have been axed. It seems as if scheduled >competition was the main reason. Of course, it was only a seasonal operation. I've heard that Australians' reaction to the 8-abreast seating and general discomfort was pretty horrified: it was only ever marketed here as a seat fill-up at back-door prices. From the British end if people will barely tolerate a 9-hour flight, how much less a 24-hour plus one! -Robin From hrose-saa@ckdhr.com Sat Mar 31 16:43:17 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 31 Mar 2001 16:43:17 From: robinjohnson@bigfoot.com (Robin Johnson) Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 28 Mar 2001 13:40:32 +1000, 202.138.58.198 Organization: North Antarctica X-Newsreader: Forte Agent 1.5/32.451 Reply-To: robinjohnson@bigfoot.com NNTP-Posting-Host: 202.138.58.198 On 27 Mar 2001 16:05:16 , Janne Salonen told us: >Boeing's thesis is that A380-sized aircraft do not have sufficient market, >relying on megahubs and connecting feeder flights, and that direct traffic >between city pairs using smaller average aircraft size (B777, A330-A340) >is going to win market share. >Charter traffic really is for package tours and the like, seldom for >regular traffic, although more frequently unsold seats are being >offered on flight-only basis. >Regular traffic requires sufficient demand to fill planes several times a >week, scheduled destinations with only one or two departures a week are >seldom commercially viable. For example Finnair has canceled such >destinations (Osaka, San Francisco, Toronto). People flying from San >Francisco to Helsinki aren't going to wait around many days for the next >scheduled direct flight, they take the first one to Europe and change. > >So, up to a point, Boeing can be right with its thesis of traffic moving >away from trunk routes, but on the other hand these will also remain, >because the traffic from, say, Helsinki to Denver will always be too >sparse to warrant a direct connection. On intercontinental or long >transcontinental routes, smaller than 250-300 seat aircraft are unlikely >to be competitive, and demand insufficient to fill such aircraft several >times a week is likely to use trunk lines and interconnecting feeders. Helsinki is one of the smaller hub cities: but I can see it being developed further in the oneWorld context for traffic from the East to Western Europe, and for traffic from the West to Eastern Europe/CIS/ and possibly Middle East, as London gets more congested than ever. An efficient smaller long-range aircraft would be useful. The MD-11s have a limited life. The 777 is really too big for the missions I have in mind. Perhaps the revitalised 767-200ER can be a possible answer for Finnair. The home market is insufficient, as you indicate, for frequent operation to most US/Canadian centres. What are the main centres of the Finnish diaspora? >Another important factor, especially on destinations between Europe and >Asia, and I suspect between the US and Asia as well, is freight traffic, >which generates a fair bit of revenue for the airlines operating these >routes. A big part of the reason why Asian carriers have been ordering >A380's is the much-increased cargo capacity it offers compared with any >other airliner, and there is also interest in cargo versions of the >aircraft. And a cargo version of Boeing's 747X seems to be the closest to >market. I haven't seen any Boeing 747-400 Long Range being sold yet, other than QF's 6. Both that and the passenger A380 address the problem current long-range aircraft have of the payload restrictions at today's everyday stage-lengths. > >It seems that A380s will have a market, although it might take some while >until Airbus sells enough planes to cover development costs. Boeing had a long period after the introduction of the 747 before it was showing a profit. >Perhaps it wouldn't be surprising if Boeing at some point tries to leapfrog >A380 and offers a still bigger plane. Within the limits of airport size and weight restrictions, of course. The 80-m _box_ is becoming the standard for size, which rather limits the _flying-wing_ shape. >One interesting alternative could in time be provided by airships, once >they can establish themselves. They should be able to offer much more >comfortable but slower flights than turbojets, and be more fuel >economical. I think this will e a very specialised market. Slower means less trips to amortise the capital expenditure over, and while this might make a very pleasant way to travel, there would be huge crew expenditure for multiple crews, particularly with the level of personal service desirable on a long trip. >Janne Salonen >Helsinki, Finland Thanks for your comments! -Robin Johnson From hrose-saa@ckdhr.com Sat Mar 31 16:43:18 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 31 Mar 2001 16:43:18 From: robinjohnson@bigfoot.com (Robin Johnson) Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 28 Mar 2001 13:40:31 +1000, 202.138.58.198 Organization: North Antarctica X-Newsreader: Forte Agent 1.5/32.451 Reply-To: robinjohnson@bigfoot.com NNTP-Posting-Host: 202.138.58.198 On 27 Mar 2001 16:05:24 , "matt weber" told us: >Actually I think reltaively few actually go through Singapore or Bahrain, >both are relatively costly for charter operators, and if all you are doing >is hauling people, cost is what counts.. I know the last one I actually >tracked (a Britannia 767-300 was leaving just before I was from MEL for >LGW) was routing through some regional airport in Indonesia (it took me a >while to figure out where it actually was, because it was a code I had >never seen before)..., and Abu Dhabi. The attraction of both places was >very low fuel and ground handling costs. >I think there is already clear evidence of that from other sources. The >Mission requirement from SQ for the SIN-LAX run is 200 pax. >However, if you look, there are about dozen routes and carriers that can >get you from SIN to LAX by stopping at various points like Seoul, Hong >Kong, Osaka, Manilla,Narita. On a daily basis, the 200 seats SQ plans for >on the non-stop is very small portion of the available lift between these >points. The 200 pax operation is going to have horrible ASM costs, so the >load will have to heavily loaded toward the premium cabins, the question is >can enough people justify the difference in fares between a SIN-NRT-LAX >versus say a SIN-LAX non-stop routing to justify a fare that is enough >higher to cover the costs? >NRT is essentiallly on the SIN-LAX great circle, so in theory a stop in NRT >might add as little as 2 hours to the total travel time, and unless the >A340-500 performs considerable faster then the A340-200/300, a good part of >that 2 hours may be lost due to the 747-400's higher cruise speeds and >ability to fly at more attractive altitudes... It's interesting that Singapore Airlines, who are trading in some of their earlier-model A340s, for reasons that are believed to include slower climb-to-altitude than competing long-range aircraft, as well as slower cruise speeds, have gone for the new A340-500s. They probably needed a lot of persuading, which makes me assume that the equivalent data for the new model will be an improvement. The engine thrust to AUW ratio is quite a bit better: I would bet that the configuration will be optimised for mostly premium passengers, as are the 747s used by United on their longest hops. Of course, you have to have premium bums in the premium seats. If most of the occupants are low-fare frequent flyers on upgrades, it doesn't work out so well, except for public relations. Perhaps this is why United is abandoning LAX-MEL nonstops. -Robin Johnson From hrose-saa@ckdhr.com Sat Mar 31 16:43:19 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:19 From: robinjohnson@bigfoot.com (Robin Johnson) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: 28 Mar 2001 13:40:29 +1000, 202.138.58.198 Organization: North Antarctica X-Newsreader: Forte Agent 1.5/32.451 Reply-To: robinjohnson@bigfoot.com NNTP-Posting-Host: 202.138.58.198 On 23 Mar 2001 17:40:08 , Wolfgang Keller told us: >What are the actual design tradeoffs today and how did the situation >evolve over the past decades to favor wing-mounted engines that much? What >would be the impact of, for example, drastically increased fuel prices >and/or significantly more strict noise regulations (=> engines with bypass >ratio >>10)? Engines these days are very reliable. It is not unknown for an engine to remain in position for five years. On the other hand, more and more ETOPS flights are being undertaken - the majority of North Atlantic crossings for example. Despite this, there have been very few ditchings. Just this month a United 767 on the climb-out from Lihue and bound for California, had a loss of power on both engines. No harm done, but..... I'm a little concerned about the dynamics of a ditching with underslung engines, though. The Ethiopian 767 off the Comores, although a hijack situation with armed men on the flightdeck, looked good on the video until the last minute, when it seemed that the engines dug in asymmetrically, causing the fuselage to break up. Does anyone know of a successful ditching by a jet? I would feel safer in a rear-engined model. -Robin Johnson (who once saw a recently-ditched Convair 240) From hrose-saa@ckdhr.com Sat Mar 31 16:43:20 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners,rec.travel.air Date: 31 Mar 2001 16:43:20 From: JF Mezei Subject: Re: Long-distance direct flights References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: wagner.videotron.net 985744728 24.202.53.146 (Tue, 27 Mar 2001 20:58:48 EST) NNTP-Posting-Host: 24.202.53.146 Janne Salonen wrote: > Boeing's thesis is that A380-sized aircraft do not have sufficient market, > relying on megahubs and connecting feeder flights, and that direct traffic > between city pairs using smaller average aircraft size (B777, A330-A340) > is going to win market share. This was the same Boeing that attempted to sell/launch a stretched version of the 747 to compete against the A380. So, one must balance that theory with the fact that for Boeing which already has a 747, the financial situation (capital availability, financing) are just not available in the USA for such a risky endeavour so Boeing is in fact prevented from doing a A380 project. So it is in Boeing's interest to find ways to downplay the importance of a A380 in the industry. In other words, a certain proportion of the "777 will take over the world" theory is spin. Already, when you look at sales, the 767 doesn't seem to be doing so well, while the A330 and 777 are doing OK. Could that be a the start of a trend towards larger planes ? Is the era of the 767 starting to fade ? (for trans-oceanic flights) Another aspect to look at is that of mergers. When two airlines merge, they will be combining traffic onto the same services on the same routes. So there would be pressure to use larger planes. If fuel prices remain high, it may also force airlines to review their strategies and perhaps combine long thin routes back into fatter trunk routes. Another aspect to consider. While it is true that there has been fragmentation in the markets, one has to wonder if the process of fragmenting may not be complete now. If so (or if it will happen shortly), once the fragmentation is done (or airports/routes/slots saturated), any growth will have to be accomodated with larger planes. Right now, there are a handfull of routes where the A380 has been identified as being viable. And there are a handful of airlines that bought the A380 for glory/image and potential future. However, every study seems to predict a doubling of passengers in the not too distant future. When you look at existing high density routes, you can't just double the number of flights to accomodate the growth. AA cannot double its New-York/London capacity by doubling its number of 767 flights, nor can it puyt the extra flights at scheduled times that are useless to passengers. So while Podunk may get its 767 to London, New York will still need its service to London and growth is more likely to happen in the NYC-London route than in the thin marginal Podunk-London route. > aircraft. And a cargo version of Boeing's 747X seems to be the closest to > market. Has Boeing launched any of the stretched 747 versions ? Airbus has launched the cargo version of the A380 for FedEx. > It seems that A380s will have a market, although it might take some while > until Airbus sells enough planes to cover development costs. Perhaps it > wouldn't be surprising if Boeing at some point tries to leapfrog A380 and > offers a still bigger plane. No, I do not think so. Boeing has tried with its 747-stretch and didn't generate enough interest. And the structure of financing in the USA/wall street is unlikely to change to allow Boeing to take such a large long-term risk. The market for the large plane isn't large enough for two competitors. Airbus was lucky because it was allowed to take just a large long term risk. In the very long term, Airbus will sell enough of these planes. But in a term where normal financing applies, I doubt that they will sell the 250 planes needed for break-even. Personally, if Airbus sells 50 planes after the first one has flown commercially, I think that the A380 will be a philosophical success. (so roughly a total of 110). > One interesting alternative could in time be provided by airships, once > they can establish themselves. Ironic that airships would be the perfect solution to transpoprt A380 fuselage parts between france and germany, but they seem intent on using trucks/barges From hrose-saa@ckdhr.com Sat Mar 31 16:43:21 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:21 From: cp@panix.com Subject: Re: How Important Is Cross-section Shape Of Wing? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news.panix.com 985743469 18946 166.84.0.231 (28 Mar 2001 01:37:49 GMT) Organization: PANIX Public Access Internet and UNIX, NYC NNTP-Posting-Host: panix6.panix.com BBarksdl wrote: > In the April issue of Discover magazine, Robert Kunzig challanges the textbook > explanation of the principles of flight. Personally I found the article less explicit (and more confusing) than this. It seemed to suggest that the mass of an aircraft must be supported by displacing an equal mass of air downward (at least, if the aircraft is gliding without engine power). But the article did acknowledge that a classic airfoil section does result in lower density air above the wing; and therefore I conclude from this that it's another way of saying that air mass has been displaced downward. The article was more explicit in renouncing the idea that lower density air pulls the aircraft upward. Fair enough; a vacuum, or partial vacuum, doesn't pull anything anywhere unless there is a higher density pushing on the opposite side. From hrose-saa@ckdhr.com Sat Mar 31 16:43:22 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:22 From: cp@panix.com Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news.panix.com 985743167 18946 166.84.0.231 (28 Mar 2001 01:32:47 GMT) Organization: PANIX Public Access Internet and UNIX, NYC NNTP-Posting-Host: panix6.panix.com CptKrell@aol.com wrote: >> What are the actual design tradeoffs today and how did the situation >> evolve over the past decades to favor wing-mounted engines that much? What >> would be the impact of, for example, drastically increased fuel prices >> and/or significantly more strict noise regulations (=> engines with bypass >> ratio >>10)? Long ago I remember reading a comparison of Boeing 707 vs DH Comet, which claimed that the 707 design of engines slung under the wing had aerodynamic advantages over the sleeker, engines-inside-the-wing approach of the Comet. As I recall (from reading this years ago) the placement of engines under the wing encourages airflow into the engines which enhances performance; someone with greater knowledge, on this news group, could make better sense of this. Certainly the four-engines-at-the-tail configuration, as in the old VC10, entailed the obvious danger that if one engine threw a turbine blade or caught fire, its adjacent engine was almost certain to be damaged. Plus, aircraft with engines mounted at the rear require the T-shaped stabilizer configuration, which, as I recall, means that the stabilizer ceases to function if the aircraft is in a nose-up position where the stabilizer drops down into turbulence from the main wing. Correct? From hrose-saa@ckdhr.com Sat Mar 31 16:43:23 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:23 From: westin*nospam@graphics.cornell.edu (Stephen H. Westin) Subject: Re: Wing vs. tail-mounted engines? References: Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM X-Trace: news01.cit.cornell.edu 985742436 1138 128.84.247.211 (28 Mar 2001 01:20:36 GMT) Organization: Cornell University X-Newsreader: Gnus v5.7/Emacs 20.6 NNTP-Posting-Host: diesel.graphics.cornell.edu Wolfgang Keller writes: > What are the actual design tradeoffs today and how did the situation > evolve over the past decades to favor wing-mounted engines that much? What > would be the impact of, for example, drastically increased fuel prices > and/or significantly more strict noise regulations (=> engines with bypass > ratio >>10)? The factors I can think of are: 1. Center of gravity. With the heavy engines at the back, but the payload forward of that, the CG has to move drastically with different loads and different distribution. That would make it more difficult to maintain consistent flight characteristics under all situations. Aren't there folk tales of unladen VC-10's and IL-62's tipping nose-up while parked? 2. Structure. Instead of carrying the weight of the engines through the wing roots and fuselage, they are attached to the part that holds them up, the wing. Likewise, the wing presumably generates most of the drag of the airplane, so you would like the engines pulling it directly through the air, rather than pushing the fuselage that then drags the wing along. 3. Clean air to the engines. I believe that MD80's and the like are somewhat more susceptible to compressor stall, especially at high angles of attack or strong crosswinds on takeoff. My wife and daughter were aboard an AA MD80 that suffered a compressor stall during the takeoff roll at DFW some years back; the pilot aborted and went back to have things looked at before trying again. 4. Maintenance issues. Others have pointed out how engines below the wing are just easier to get to. 5. Simpler mounting of four engines, though this only matters for the 747 and A340 these days. In the '60s, there were the VC-10 and IL-62. I think the DC-9 and 727 got rear-mounted engines in part so they could sit lower to the tarmac for easy access at primitive airports. Both have rear integral stairs, at least in some configurations. Boeing worked around that for the 737 by squishing the engines in between a low wing and the ground, which created a challenge in mounting higher-bypass engines. But that all is a moot point except for regional jets these days, and they have tended to stick with rear-mounted engines. I suspect that a minimum engine distance from the ground is also desirable to avoid inhaling foreign objects from the ground. -- -Stephen H. Westin Any information or opinions in this message are mine: they do not represent the position of Cornell University or any of its sponsors. From hrose-saa@ckdhr.com Sat Mar 31 16:43:24 1901 Path: bounce-back Newsgroups: sci.aeronautics.airliners Date: 31 Mar 2001 16:43:24 From: "matt weber" Subject: Re: How Important Is Cross-section Shape Of Wing? Message-ID: Approved: hrose-saa@ckdhr.com@ditka.Chicago.COM Sender: hrose-saa@ckdhr.com@ditka.Chicago.COM Content-Type: text/plain; charset="us-ascii"; format=flowed At 04:05 PM 3/27/01 +0000, you wrote: >In the April issue of Discover magazine, Robert Kunzig challanges the textbook >explanation of the principles of flight. I have always felt the books were >wrong on this when they say that the shape of the wing invokes Bernoulli's >Principle to provide the lift required. Kunzig refutes the role of Bernoulli's >Principle. He says that planes fly by pushing air down, getting lift from the >equal and opposite reaction that pushes the plane up. I'm trying to reconcile >that with my own thoughts on the subject - that the forces that cause an >airplane to fly are essentially the same as those that cause a kite to fly. >Either way you look at it, the shape of the wing is not the main element. >Otherwise, how could a plane fly upside-down? As an old barnstormer was >reported to have said, "Give me enough power, and I'll fly a barn door." There are actually several different lift mechanism at work. The speed and purpose of the aircraft largely determine which methods you want to use. Low speed lift, very high flying subsonic aircraft like the U2/TR1, light aircraft and gliders generally do depend upon Bernoulli for lift. This is probably the most efficient lift. Leading edge extensions don't do much good for anything except Bernoulli. In these aircraft,wing cross section is key. As the speeds go higher the lift tends to become primarily momentum exchange (pushing the air down). At supersonic speeds, it is almost all momentum exchange. At very high speeds, the shape of the wing impacts the shockwave formation, but all that really matters is the area. The F104 wings produced almost no aerodynamic lift. Upside down flight generally requires much higher speed and higher angle of attack then right side up flight because it uses momentum exchange lift as opposed to aerodynamic lift. Matt Weber