Re: A340

From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works
Date:         02 Feb 94 13:27:35 PST
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>One of the reasons that the A340 didn't go with a larger engine
>(perhaps the PW2000 series) is that there was a strong sentiment
>to put a "French" engine on the "French" aircraft.

While there may be some truth to that, weight and expensere were
probably far more serious concerns.  The CFM56-5C series used on the
A340 has a dry weight of 5,700 lbs. and is somewhat less expensive
than the far heavier PW2037 at 7,160 lbs. or RB.211-535 at about 7,100
to 7,300 lbs., depending on exact model.  Scaling either of these
engines down to the size needed by the A340 probably would not have
saved enough weight as they are fundamentally larger (hence heavier)
engines.

>Indeed one of the reasons that the aircraft has four engines
>is because of the lack of available powerplants at the time of 
>its development.  The CF6 and PW4000 derivatives available 
>then just wouldn't give it the sparkling range performance
>that Lufthansa was looking for.

The CF6 and PW4000 could easily have given the range performance --
they already give nearly that range performance on the 747-400 which
is nearly twice as heavy.  Trouble is, you'd have to schlep around a
lot more fuel (no problem with the extra power but you've got to buy
the stuff) and you'd have to *pay* for those engines, which would
drive the A340's price tag up to, or beyond, 747-400 levels.

The A340 seems to be something of a compromise.  They're really
pushing the CFM56, and there's probably not much growth room left in
that engine.  But the next step up in engines is too big, heavy, and
expensive, plus would be incompatible with existing A340 fleets.  A
tri-jet with the bigger engines might have been a better choice, but
that would have had significantly less commonality with the A330,
driving up costs while also introducing the hassles of an afs-mounted
engine.

Long-term, I expect the A340 will follow in the footsteps of the
DC-8-62 and 747SP -- impressive performers for which there just isn't
that large a market, and which are rapidly eclipsed by more versatile
aircraft.

--
Karl Swartz	|INet	kls@ditka.chicago.com		
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