Helowriter wrote:

Different kind of flaw tolerance -- this is the structues/dynamics
margin to take damage and keep flying. It could be big stuff like a
real hard landing or ballistic damage, or small screwups like a guy
dropping a toolbox on a composite fairing. The point is cracks don't
propagate, and you keep flying. It's a complicated thing with new
design, test, and qualification tools that weren't available before.
Sikorsky first civil certified that for the S-92 in 2002, and it has
big payoffs for military applications -- Of course the Navy decided to
pass on the Presidential competiton, but that's their insanity.

Composites were developed for military aircraft and were in use long
before Sikorsky got them civil certified or used them on a commercial
product. Again, composite technology isn't a military derivative of a
commercial development.

Yep, 64B was the notional multi-stage improvement program considered
before the C/D evolution that became the D to save money on manuals --
yes, I go back that far. My point was the 530F gave Boeing the
opportunity to design, fabricate, and certify/qualify a composite blade
while the Army thought about it, and thought about it. You don't just
go and do stuff like that, and that's why multiple civil/military
programs give you opportunities to develop dual-use technologies.

Ah, notional programs. Actually, there was bit more to the story than
saving on TMs. The AH-64D was the AH-64C with -701C engines and the FCR
installed. Changing the aircraft designation simply because of a kit
installation didn't make much sense. If the FCR goes TU and you pull the
MMA and/or LPRF, but you leave the -701Cs and torque tube in it, what is
the aircraft designation? AH-64C1/2, AH-64Dminus? It was causing all
sorts of problems with building the IETM, the engineering documentation,
the courseware, etc. Don't know why the Army decided to drop the C
altogether and choose the D designation - flip of a coin, maybe.

Yes, you do "just go and do stuff like that". Since when has it been a
requirement to have a technology certified on a civil aircraft before
using it in a military program? Why do you have to have your own
commercial operation in order to develop dual-use technologies? Why not
license it to an existing aircraft manufacturer without taking on the
burden of creating your own full-up aircraft product line? If Boeing can
work the bugs out of the Dragonfly technology, the civil applications
are substantial. Does not having a commercial operation mean that Boeing
can't get it certified for use unless they build the aircraft themselves?

Not having MDHI didn't stop Boeing from developing composite blades or
LWW or FCDB or . . . . Not having a commercial operation hasn't stopped
the Phantom Works folks at Mesa from developing any of the items that
they're working on. It hasn't stopped the rotorcraft engineers from
developing anything new for any of the other aircraft built there. It
hasn't stopped them from looking for civil applications for anything
that they're working on, either. Not bleeding cash into a losing
commercial operation has, however, freed up funds for doing in-house
research.


The same with the Bell 430 four-bladed composite yoke that started out
as the 630 rotor (I don't know where they got the designation from).
They knew the obvious application was the Marine Cobra, but it took a
decade for the Marines to do it. Meanwhile the 430 put the thing into
production and got it certified.

Bell claimed over 80 orders in 18 countries for the 609 in 2003. How
many they lost during the testing pause while they ran out of money I
don't know. They just did a helo-airplane conversion on a ground rig,
and they're supposed to do an in-flight coversion by the end of the
year. They ran out of bucks, let the thing sit, and recruited Agusta
as a partner -- that's the rotorcraft opportunity Boeing missed.

Good holiday, folks

HW

Hmmm. So, Boeing dropped out as a secondary partner from an unproved and
as yet to be produced commercial venture. Is it necessary to have your
own commercial operation in order to partner with someone that does?
Boeing doesn't build civil rotary wing aircraft - does that mean that
they can't join up with a prime that does? Why does Boeing need it's own
commercial rotary wing business in order to develop technologies for
civil use?

Cheers,

Vygg