In article ,
"Spiv" writes:

"Steven P. McNicoll" wrote in message
ink.net...

"Spiv" wrote in message
...

Then pay attention.

What for? It's clear you don't know what you're talking about.

Where do you have a problem, then I ca help you.

You didn't get the point. Please focus.

You didn'r make a point. The point is nothing from the Comet went into
the
design of Boeing's bombers or the 707.

The engineering/metallurgy side did. You know too much about these sorts of
things do you?

Horse****, Spiv!
Go peruse the U.S. Natioanal Advisory Comittee Technical Reports
availalable online through the NASA Tech Reports Server. Then check
out the UK Aeronautical Research Comittee papers available from
Cranwell, also available online, and searchable through the same
server. (Reciprocity is a good thing). You'll find that, if anything,
the information flow, wrt structures, and the fatigue bahavior of
metals, went the other way. (US-UK). U.S. work on, and concern with,
metal fatigue began in the 1930s. And was continually refined.

DeHaviland had been warned many times about the choices that they had
made in the design of the Comet's structure, but they felt that their
use of Redux Bonding to join metal parts gave them superior
performance. (Turned out that they couldn't use Redux in many areas,
and so, it was back to drilled holes & rivets.) Eastern Airlines
evaliated the COmet prototype in 1950, and rejected any consideration
of it due to concerns about the fatigue resistance of the structure.
Nobody at DehHaviland seemed to be paying attention.

DeHaviland made a number of bad choices in the design of the Comet
I/IA. The airfoil provided knife-edge takeoff performance, for
instance. On taneoff, a Comet had to be rotated to exactly 10 degrees
AOA, at exactly the right speed, or it wouldn't take off. An early
pullup, or anything over 10 degrees, meant that the increased Induced
Drag would keep the airplane from accelerating. A late pull, or an
AoA of 9 degrees, meant that there wasn't a runwal in All of
Christendom, (or, for that matter, Karachi, Pakistan), that was long
enough for the Comet to get off the ground. When you add in the other
accidents that wrote off Comets, about half of all Comet I/IAs that
were built were total losses before they were pulled from service.

The 707, and, for that matter, the 367-80, used an entire different
philosophy in structural design. It was designed with multiple load
paths and a fail-safe structure, such that small problems would be, as
far as possible prevented from becoming big ones.
Don't forget, that between teh B-29, B-50, B-377/C-97, B-47, and B-52,
All of which flew before the COmet was grounded, Boeing had more large
pressurized airplane and large jet airplane experience than the rest
of the world, combined.

To add some Military Content. The groundings and losses did not
necessarily mean the immediate scrapping of the Comet I. DH _did_
infact, come up with a rebuild program that would allow the airplane
to have some useful life. The only Comet Customer who took them up on
this was the Royal Canadian Air Force, which had purchased two Comets
to support the First Air Division in Europe. These remained in
service until the early 1960s.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster