Re: Safety and design rankings (was Re: Flight controls)

From:         Robert Dorsett <rdd@cactus.org>
Date:         16 Dec 92 14:00:40 PST
References:   1 2 3
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In article <airliners.1992.163@ohare.Chicago.COM> kls@ohare.Chicago.COM (Karl Sw
artz) writes:
>In article <airliners.1992.144@ohare.Chicago.COM> rdd@rascal.ics.utexas.edu wri
tes:
>My understanding was that the 747-400 does *not* have a new wing but
>rather a tweaked version of the original.

There were significant changes in structure and composition, plus the 
addition of the wingtip extensions and the winglets. As I understand it, 
the new wing is intended to support both the 747-400 and a full-upper-
deck 747-500.


>I recall some statement
>from Boeing regarding the lack of winglets on the 777, which noted
>that the 777 had a new wing and starting from a clean slate it was
>more efficient to not have them, whereas working from an existing
>design as with the 747-400 it was helpful to have them.

One doesn't really relate to the other: the 777 has a high-aspect-ratio
wing, reducing drag in its long-range profile.  The drag reduction is
what the winglets were purportedly for; the 777 will achieve a better 
effect, naturally.


>>                    INS/PMS, conventional otherwise
>
>Ok, I'll risk it ... what's PMS?  (We're talking about airplanes!)

Performance Management System.  It's the precursor of FMS's; it was
originally deployed on the 747-SP.  It was used to provide a lot of "nice
to know" and performance-related flight guidance, to obtain optimal 
fuel burn.


>Every first-generation 737 I've seen has a third seat for the flight
>engineer.

Hmm.  I have some vague recollection of a three-man 737, but I think I'm
thinking of that 767.  The 737 was designed for a two-man crew.  If three-
man ships were produced, there are precious few of them.  I wasn't able 
to find any explicit references to three-man variants in my notes.

Be careful to distinguish between a "flight engineer" and someone occupying
the jump seat.  Quite a few airlines will run a "third man" due to either 
union pressures, or to provide training experience for new-hires; one often
sees "transients" (instructors, check pilots, deadheading pilots) in
the jump seat.

Lufthansa, I believe, ran a third man on the 747-400 for a long time; Air 
Inter's unions had a major fight over the A320.  The 737 itself is certifi-
cated for two-man operation, and that's what is legally needed in order to 
fly it.

It's an interesting question whether the union desire to safeguard its
members' economic interests might actually *decrease* safety, in this case.
I question the wisdom of inserting a third man "for the ride," who has
no real operational significance in the cockpit.  It would seem that such
a person could serve as a destabilizing influence.  If they're going to 
go three-man, they should go whole-hog, and give him something to do, in
the fundamental cockpit design.  But I digress.


>I believe this was one of the selling points of the DC-9
>over the 737.

Yet ANOTHER excerpt from _Legend & Legacy_, pp. 255-257:

"The DC-9 head start was a killer for Boeing's sales force, yet it
wasn't the only handicap Boeing's new baby faced in its adolescence.
A deep hole was dug by the men who would fly the plane, and unwittingly
it was Delta's pilots who handed their brethren the shovel that almost
buried the 737.  When Delta bought the DC-9, it won an agreement from its 
pilots that the cockpit be designed for a two-man crew, eliminating the 
flight engineer.  This was permissible under an FAA regulation that 
allowed any jet transport weighing less than 80,000 lbs to be flown by two 
pilots.  Both the original DC-9 and BAC-111 met the so-called '80,000-pound 
rule,' heresy and anathema to the Air Line Pilots Association (ALPA).  
It could do nothing about the precedent Delta's pilots had set for the 
DC-9, but the union began pressuring the FAA to change it regulation for 
the 737, and at the same time warned US airlines planning to buy the 
Boeing jet that future pilot contracts would specify a three-man crew for 
the 737.

"ALPA argued that with no flight engineer to help them, the pilots'
increased workload made it difficult to watch out for other traffic, thus
enhancing the chances for mid-air collisions, and also created more 
danger during bad-weather landings.  The union's case might have sounded
logical until one began wondering why a two-man crew was safe for the DC-9
and BAC-111, and not for the 737.  Nevertheless, the FAA changed its 
regulations to the extent of requiring Boeing to prove that the 737
could be operated safely with two pilots.  The irony was that once having
been certificated for a two-man crew, three subsequent larger DC-9
models weighing far more than 80,000 pounds also were automatically 
certificated for two pilots, but not the 737.

"Thus the baby Boeing's late start was saddled with a further sales han-
dicap--many airlines considering the 737 bought the DC-9 instead, 
unwilling to add the expense of a third cockpit crew member who literally 
was nothing except an extra set of eyeballs.  United and Western, 
after arbitration, agreed to a three-man crew, although that third
man was a classic case of feather-bedding--or 'feather birding,' as
then-FAA administrator Najeeb Halaby expressed it.

"Western's pilots referred to the extra crew member as GIBs, for 'Guy
in Back,' but abandoned this nomenclature hastily when a pilot ran
across the word 'gib' in a dictionary and discovered it meant castrated
tomcat.

"Lew Wallick once asked a Piedmont captain what the third crew member did,
riding in a jump seat just behind the pilots, unable to reach any controls.

"'He doesn't do much,' the captain admitted.  'He sits back there and 
spills coffee in my brainback [nickname for the briefcase holding air-
way maps and aircraft manuals].  But come next summer, he's gonna mow my
lawn.'

"Brien Wygle was in charge of the 737's flight test program, and worked 
with engineering to design a cockpit whose workload would put the least 
possible stress on two pilots.

"'We went to a lot of trouble proving this out,' Wygle said.  'We didn't
have much computer input--they weren't as sophisticated then--but we
designed a simple cockpit management system because the FAA told us that
when we came up for certification, they were going to be very tough.  They
were under great pressure from ALPA, which wanted the FAA to say that 
the 737 needed a flight engineer or any third crew member.'

"Tough they were.

"'The FAA made us jump through a lot of hoops,' Wygle recalled.  'There
was an unprecedented amount of testing, all kinds of simulated engine and
systems failures, low-visibility approaches and landings, and even test 
flights through high-density traffic on the eastern seaboard.  And to the
FAA's credit, they ruled that the 737 was completely safe to fly with a 
two-man crew.

"The ruling, however, couldn't recoup the sales Boeing had already lost
because of the ALPA campaign; the union itself eventually came around to
admitting that a sophisticated, well-designed cockpit didn't need a flight
engineer [MUCH later! --rdd]  And in one sense, ALPA did the 737 a
favor.  It forced Boeing to improve the plane to the point where it would
be so good it didn't matter how many men were in the cockpit."


>I've always wondered just what the flight engineer really does on a
>767 equipped for three flight crew.  I believe QANTAS does this.

There was only one 3-man 767 built, and that was for UAL.

Ansett uses a three-man crew, but there's no major change to the structure--
probably just a CDU interface on the rear on the control pedestal, so the
third man can play navigator, to keep busy.  Again, be sure to distinguish
between a "GIB" (:-)) and someone who plays an intended operational role 
in the cockpit.


>Also, some A310s lack the FFCS (Forward Facing Crew Cockpit) having
>instead what I assume is a cockpit more like an older A300.  All of
>these are due primarily to union/labor pressures.

This is the first I've heard of it.  Got any references?  It'd be REAL
difficult to do, and I'd question whether the returns would be enough
to entice the manufacturer to do it.


>>Performance is now ensured by legal contract, rather than design,
>>with the dollar being the bottom line.
>
>Well, mandated, at least, if not ensured.

I suspect that when dollar figures reach low earth orbit, performance is
whatever you say it is. :-)


Two good references:

Incidentally, there are good design summaries of the 757/767 and 
A310/A300-600 cockpits in _Aerospace Crew Station Design_, G. P. Carr, 
editor, Elsevier Science Publishers, 1984.  

There's also a superb design overview of the 737 in the February 3, 1966 
issue of FLIGHT INTERNATIONAL.





---
Robert Dorsett
rdd@cactus.org
...cs.utexas.edu!cactus.org!rdd