Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Re : SSME Vs. F-1
Message-ID: <1990Dec11.163830.10045@zoo.toronto.edu>
Organization: U of Toronto Zoology
References: <6241@crash.cts.com>
Date: Tue, 11 Dec 90 16:38:30 GMT

In article <6241@crash.cts.com> gandalf@pro-canaveral.cts.com (Ken Hollis) writes:
>... The F-1's were one time, throw away engines...

"One time, throw away" engines that were designed to be fired 50 times,
please note.  There is really no such thing as a "throw away" engine with
regenerative cooling; they are all reusable if they can be recovered.

>... Basically what it boils down to is that LH2 has a much better
>"W" than RP-1 because of the density of the fuels and the energy released. 

No, actually, the major advantage of LH2 is its low molecular weight.  Its
density is a major *dis*advantage, because it requires enormous tanks, to
the point where studies for single-stage-to-orbit systems often conclude
that a denser fuel is superior despite lower specific impulse.

>If you are interested in the design of liquid rocket engines, I suggest
>"Design Of Liquid Propellant Rocket Engines" NASA Publication "NASA SP-125",
>1971...

Actually, the Sutton book (Elements of Rocket Propulsion, I think -- my
copy is at home) is a better place to start:  it's in print, unlike SP-125,
and gives a broader overall discussion with a gentler lead-in, and also
a more current discussion of some issues.  SP-125 is for hard-core techies.
-- 
"The average pointer, statistically,    |Henry Spencer at U of Toronto Zoology
points somewhere in X." -Hugh Redelmeier| henry@zoo.toronto.edu   utzoo!henry