Re: Boeing 777 Wing

From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
Date:         09 Nov 94 00:51:22 
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>... what about the folding wings?  I understand that it was supposed
>to be an option.

Airliners were more worried about the weight and complexity than they
were about fitting the 777 into gates, so Boeing offered them the
option of installing the hinges and such but not the mechanisms to
actuate the whole thing.  This produced a 1,900 or 2,000 lb savings,
and nothing to go weird in flight, while preserving the option of
installing the folding mechanism later if desired.

United, the 777 launch customer, still wasn't happy about the weight,
as they wanted non-stop Chicago to Hawaii range.  Their initial order
specified an increased MGTOW of 525,000 lbs (vs. 505,000), and fixed
wingtips without even the hinges or provisions for folding, a savings
of 3,900 lbs over the folding design.  Boeing relented after devising
a way to build both variants without dramatic tooling changes.

>Have any airlines ordered the plane with the folding wing option?

No, though as far as I know it's still an available option.  I think
Boeing was planning on putting folding wings on one of the aircraft
for certification purposes, though as far as I know all of the orders
are for permanently fixed wings.

>Also, how does the 777 compare performance wise with its competitors, the
>A340 and MD-11?  Did Boeing use the late start to its advantage by
>capitalizing on the 777's competitor's shortcomings (after observing
>feedback from customers of the other aircrafts)?  

>From what I've heard, the 777 has met or exceeded its fuel consumtion
and performance goals from day one, in contrast to the well-publicized
problems with the MD-11.  I don't really know how the A340 did, but
shortfalls are fairly common.

In a more general sense, Boeing certainly capitalized on their late
entry in one very big way -- newer engine technology, which through
higher thrust permitted Boeing to offer an aircraft in the same
general range and payload class as the A340 and MD-11, with the
economic benefit of having only two engines.  There is a catch in
this, though, since you either have to get ETOPS right away or not
need ETOPS.  While United originally needed 180-minute ETOPS for
the Hawaiian routes, it would not have hurt too much to keep them
on 48-state/Canada/Alaska routes at first.  Now that United has
switched the first batch from domestic to international aircraft,
they can manage with 90-minute ETOPS for trans-Atlantic flights (or
no ETOPS for South America) but United's experience with ETOPS makes
it a fair bet that they'll have ETOPS from day one.  In contrast,
Virgin Atlantic chose the A340 over the 777 in part because the 777
would need ETOPS, which Virgin, with no ETOPS track record, would
find hard to obtain.  Except possibly for London to Hong Kong the
777 without ETOPS would have been useless.  (Airbus was also able
to offer a good deal on four aircraft with only a few months lead
time due to Northwest's late cancellations.)

--
Karl Swartz	|INet	kls@ohare.chicago.com
1-415/854-3409	|UUCP	uunet!decwrl!ditka!kls
		|Snail	2144 Sand Hill Rd., Menlo Park CA 94025, USA
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