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From: ems@amdahl.UUCP (ems)
Newsgroups: net.columbia
Subject: Re: SRB vs liquid
Message-ID: <2774@amdahl.UUCP>
Date: Mon, 10-Feb-86 14:41:53 EST
Article-I.D.: amdahl.2774
Posted: Mon Feb 10 14:41:53 1986
Date-Received: Wed, 12-Feb-86 20:11:41 EST
References: <615@uwvax.UUCP> <1759@jhunix.UUCP>
Organization: Circle C Shellfish Ranch, Shores-of-the-Pacific, Ca
Lines: 20
Summary: How to throttle a SRB.

> First, remember that liquid fueled rockets are a much older technology
> than modern type solid fuel rockets(fireworks notwithstanding).  In fact, if
> I remember my history right, Goddard's rockets were liquid fueled.  Liquid
> fuels are generally volatile (i.e. H2, O2), poisonous (N2O4, CH3NHNH2),
> or both.  They can be unstable
> at room temperature, require high pressure/low temps to stay liquid,
> and in general are a pain to handle.  Solid fuel, on the other hand, 
> is easy to handle, stable, and generally nontoxic (aluminum powder and
> ammonium perchlorate), or at least a lot less so than N2O2.  The advantage
> liquid fuel has is that its combustion can be more easily controlled
> than solid fuel rockets (how does one put a throttle on a roman candle?).

One way is to have a solid *fuel* rocket, but to valve the oxidizer in
as a gas or liquid.  I think it has been done before, but don't know
the particulars.  This is really a hybrid rather than a pure solid
rocket, but what the heck.
-- 
E. Michael Smith  ...!{hplabs,ihnp4,amd,nsc}!amdahl!ems

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