Re: Singapore Airlines The A340 vs 777 saga continues

Date:         23 Jul 99 04:18:21 
From:         "Matt727" <Matt727@msn.com>
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Tim Lee wrote in message ...
>Hang on a minute, James!
>
>Frankly, 6.5 tons is not a huge amount - not at this stage of
>development, anyway.........

Not a huge amount?  If you say so....

>>The run to Europe from Singapore in an A340 is nearly an hour longer
>>than it is in a 747, or a 777.  It is extra travel time, and it
>>complicates connections within Europe.
>
>The 747 is a quick aircraft, but I doubt this is true for the 777, which
>has a stated cruise of 30kts less than A340.

747    Mach .85
777    Mach .84
A340 Mach .82, but it has to go slower for the long range.

I'm sure Airbus has quoted the 340s speed in knots at a different altitude
in order to make the numbers look like the airspeed is faster.  Ground Speed
and Airspeed are two different things and the way they compare varies with
altitude.

>>Airbus Aircraft are traditionally not 'high flyers'. This is also
>>causing SQ a certain amount of pain. Flights to Europe generally
>>depart in the late afternoon and early evening, and are at or very
>>near MGTOW.  The trip goes out of over the Bay of Bengal, which often
>>has nasty weather (thunderstorms) in the early evening. Very bluntly,
>>at high weights, the 777 and the 747's can fly a lot higher, giving
>>the crew more choices about how to avoid weather (and provide a better
>>ride for the passengers).
>
>Prove this one, please!  AI aircraft have a similar climb rate to the
>777, and the 747 climb performance can be dismal...  Also, no-one can
>convince me that any aircraft in commercial use can climb over a cu-nim
>cloud - they can peak at over 60,000ft.....

It has nothing to do with how fast it can climb... it is about wing loading.
As you go higher the air gets thinner.  So if you are at MTOW in a A340 you
cant climb way up high because the thin air wont support the aircraft.  Now,
if you have a big Boeing wing you can go right on up.  That is how it works.
Wing loading and air density at altitude.

>>The other operational issue is the routes from SE Asia go over India
>>on the way to Europe or the Middle East. A300/A310's are very popular
>>regional aircraft often transiting India on the way to or from the
>>Middle East or destinations on the sub continent, couple that with the
>>normal long haul traffic out of SE Asia , and it tends to make the
>>altitudes where these aircraft live very congested, so unless you are
>>lucky, or can fly above FL350, (which is very hard to do in an Airbus
>>at realistic operating weight), you may well get shoved down at a very
>>unattractive altitude, like FL260.
>
>AI products do this without problem - VS toc is typically 39,000 on the
>HKG-LHR with a 340.

Sure, maybe at a LOW aircraft weight.

The A340 has the same wingspan as the 777, but the mean chord is way less
therefore creating a wing with less area.  (I hope no one at Airbus reads
this... then they would know how to make a good airplane!  (a bigger wing
also adds fuel capacity!)

>Do we work for Boeing by any chance?

........and where do you work?

--
Matt
Student Pilot
Seattle, Washington
Fly Boeing on Alaska Airlines.
91' 240SX SE