Re: Confusion over 777 variants.

Date:         22 Nov 97 20:41:24 
From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
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>>Right.  There were also some references to an A+ market version, which
>>was the A market plane pushed somewhat, but not nearly up to the IGW
>>weights and range.
>
>I've seen references in some books to 3 tiers of -200 A market, with
>increasing weights and engine power.  That is seperate from the -200IGW.

Boeing usually lists "standard" and "option" figures for any given
model.  An airline can order one of a number of variations between
these extremes.  On the 777-200 (non-IGW), MGTOW now ranges from
506,000 lbs (229,520 kg) to 545,000 lbs (247,210 kg).  United wanted
greater range, so their launch order was for 525,000 lbs MGTOW; they
were delivered at 535,000 lbs and have since been upgraded to the
full 545,000 lbs.

Similarly, the 777-200 IGW ranges from 580,000 lbs (263,090 kg) to
632,500 lbs (286,900 kb) MGTOW.

>>this market.  One proposal was a 777-300 with a fuselage shortened by
>>33'3" (i.e., the same length as the -200, but with the stronger
>>structure of the larger aircraft), another was for a 720,000 lbs MGTOW
>
>Interesting hybrid.  They'd probably take out the 5th door then I
>suppose.  Soudns like a -200 with the wing and wingbox of the -300.

I'm sure it would have no more than four doors.  In fact, I'm not sure
how it would differ from a -200 with an IGW wing and engines.  Boeing
describes the BBJ in similar terms -- the airframe is described as a
737-800 shortened to the same length as the 737-700, rather than being
a 737-700 with structural and engine enhancements from a -800.

>>   Boeing is studying a derivative of the 777-200 that could fly
>>   nearly 10,000 miles, as well as a longer-range derivative of
>>   the 777-300.

>I wonder how far the could push it.  They still aren't storing fuel
>outboard of the wing-fold lines are they?

The only additional fuel on the IGW is a center tank, so if the base
design doesn't have tanks beyond the fold lines then that's still the
case.

>And they can also use the horizontal stab too.

The 777 is Boeing's first design which uses composites for the primary
structure of the horizontal stabilizers.  I don't know how that would
impact the potential use of that area as fuel tankage, but I've heard
that Boeing has no plans to put fuel there.

>I'd love to see how far it could go using all of the available fuel
>storage options.

Optimizing for a low passenger count (lots of premium seats with
relatively few economy seats) and little or no freight, they can also
sacrifice some cargo hold space for fuel tanks.  The MD-11(ER) and the
longest-range 737 options take this approach.

>Ok.  Blue skying.  I don't see the point in a larger stretch:
>1. The -300 is the longest airliner already.  Making it longer could make
>airport handling 'interesting'.

Maybe.  I don't know if a further stretch would be enough to make that
a significant issue.

>2. It'd compete with the 747-400, and possibly the -500/600 plans to some
>degree.

But those are *much* longer range aircraft.  As long as a further 777
stretch doesn't have very long legs, the only current 747 it competes
with is the 747-400(D).

>Personally I was kind of surprised that they kept the MD-11 in production
>beyond just filling existing orders.  You'd think the 777 would be the
>pick of the litter to take that entire market.

It doesn't appear to be able to handle the weight in cargo apps --
AvLeak's Source Book lists the cargo capacity of the 777-200 IGW as
only 56,500 lbs, whereas the MD-11 Combi (the F isn't listed) has a
whopping 144,300 lbs capacity.

In addition, some carriers don't care for ETOPS, though I can't see
any of those who aren't already MD-11 customers choosing the MD-11
over the A340.

--
Karl Swartz	|Home	kls@chicago.com
		|Work	kls@netapp.com
		|WWW	http://www.chicago.com/~kls/
Moderator of sci.aeronautics.airliners -- Unix/network work pays the bills