Re: Engines for B747X

From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
Date:         13 May 96 02:08:44 
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>IMHO, GE probably had mis-sized the GE90 that they now have to
>develop a new engine for the proposed B747 derivatives.

Is 70,000 lbs (as on the A330) the practical limit for the CF6-80?
If so, perhaps that has something to do with the A330 being the first
Airbus airframe on which GE hasn't had the largest share of the engine
market.

Still, the 747X requirements are only a bit lower than those of the
777 (77,000 lbs on the A-market model).  A slightly de-rated GE90
would suffer weight disadvantages but it still might be competetive.

>However, it is puzzling why Pratt can't do it alone, after all the
>cores for the PW4168 and the PW4084 are almost identical.

The Wall St. Journal had a big article in last Thursday's edition that
seemed to imply that Boeing pushed them into it.  Presumably, despite
Boeing's assertion after the original 747 that they would never again
offer an airliner without a choice of engines, they've decided that
the financial advantages of limiting engine options are just too great.
(Both the second and third generation 737s offer only CFM-56 engines.)

The next day, the WSJ was reporting squables between GE and Pratt over
the project.  Surprise!

>Nevertheless, the long-term financial implication of the joint venture
>for the two engine companies is tremendous, and Rolls will have an even
>tougher time to fight the two giants. Rolls says they will offer a
>Trent 700 derivative for the new aircraft.

On the surface, this seems like a major blow for Rolls.  However,
several likely 747-500X/600X customers already have Rolls-powered 777s
on order.  With the GE/Pratt joint venture, Rolls will offer the only
engine that can power both the 777 and the 747-500X/600X.  That seems
like a major advantage for Rolls.

--
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