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From: cfiaime@ihnp3.UUCP (J. Williams)
Newsgroups: net.aviation
Subject: Re: Commercial aircraft power-to-weight
Message-ID: <207@ihnp3.UUCP>
Date: Mon, 30-Dec-85 10:06:56 EST
Article-I.D.: ihnp3.207
Posted: Mon Dec 30 10:06:56 1985
Date-Received: Tue, 31-Dec-85 03:32:26 EST
References: <59200011@trsvax>
Reply-To: cfiaime@ihnp3.UUCP (45261-J. Williams)
Organization: ATT Bell Labs
Lines: 28

In article <59200011@trsvax> gm@trsvax writes:
>
>

>Of the currently flying (subsonic) airliners, which 
>one has the highest power-to-weight ratio?
...
>Subjectively, the fastest accelerator seemed to be a Boeing 737 with 
>Rolls-Royce something or other engines.

Your twin engine airliners must, by regulation, have a much better 
power to weight ratio than the three or four engine airliners.  FAR 
Part 25 (large aircraft certification) specifies a positive rate of
climb with one engine out.  On a twin, you have to climb on 50% power,
while on a four engine airplane, you can use 75% power.  

What it all boils down to is that twin engine FAR 25 airplanes are quite
good in takeoff and climb.  

The 737 has always had good performance.  In later versions, such as the
300 series, performance has been greatly improved.  100 and 200 series
airplanes use the Pratt&Whitney JT8D engine, while the 300 series uses
the SNEMCA CFM56-5.  Look for new variants of the airplane in the next
few years.

					jeff williams
					ihnp3!cfiaime
					AT&T Bell Laboratories