Re: FT: Missiles and Gas Tanks

John W.F. McClain wrote:
> 
>      First, don't ICBM's use liquid fuels?  And presumably cruise
>    missiles use some kind of jet fuel.  But second, I actually thought
>    solid fuels were more efficient than liquid fuels, which would
>    explain why they're used, for example, in the Shuttle SRBs.  You
>    can't turn them off is (I thought) the biggest problem.
> 
> The Titan II ICBM, and most (all?) of its American predecessors (Titan
> I, Atlas, etc.) were liquid fueled.  The Minuteman and Peacekeeper
> (AKA MX) are solid fueled.  A silo in the middle of no-where is a much
> more stable controlled environment than a ship pitching around on the
> seas (or space) with a hundreds of crew (the sea/space is a harsh
> mistress after all).	Having said that I believe the early American
> Sub-Lunched Ballistic Missiles (SLBMs) (Polaris and Poseidon) were
> liquid fueled, different time I guess.
> 
> The Harpoon and Tomahawk both use jet engines and jet fuel, but I
> imagine jet fuel is not nearly a volatile as liquid rocket fuel (don't
> need the oxidizer right there after all).
> 
> In terms of efficiency it is the other way around, liquid rocket fuels
> are much more efficient/unit weight.	The Titan II has a much longer
> range than it successors (and USSR ICBMs making it relatively safe
> strategicly) but the maintenance difficulties with liquid fuels
> prompted the US Air Force to switch to solds.
> 
> For example I believe the Titan II was the first US ICBM where the
> fuels could be stored inside the missiles indefinitely (liquid rocket
> fuels tend to be corrosive), previous ICBMs need to be fueled
> immediately before launch (for the Atlas this fueling had to be cared
> out above ground and took 30 minutes!).  I believe part of the reason
> for Minuteman's name was that because it was sold fuel the pre-lunch
> prep-time was very short (0?).
> 
> A couple years ago their was a crisis at a Titan II silo when someone
> working on the missile dropped a spanner down the side of the missile,
> there was a major worry that the spanner might have pictured the
> missile's tanks...very, very bad on a ready for flight liquid fueled
> missile.
> 
> --
> It could be said that without sticky tape there would be no such thing
> as biocontainment.		  -Richard Preston
> 
> I am solely responsible for contents of this message.  It does not
> necessarily reflect the opinions of Lockheed Martin or its customers.
> 
> John W.F. McClain		    Lockheed Martin Information Systems
> jmcclain@lads.is.lmco.com	    37 North Ave.
> Work: (617) 505-9536		    Burlington, MA 01803

No offence, but .... IMHO, discussing what CURRENT missle technology
uses for engines/fuel is ok.  But it disturbs me when peaple seem to
think that all future missle developments will continue to use the SAME
technology used today.	At some point, space/atmo propulsion technology
is going to turn out something that surpasses any liquid/solid fueled
rockets.  Manned military spacecraft (the ones of interest to us...)
will allways use the best engine tech available.  And when that tech
(whatever it is...) surpasses liquid/solid fueled rockets, the missles
built after that, will (in most cases) switch over to the new
technology.  Most of these space battle games are set very far from
today, it is safe to say that most of them will use small ship engines
in their missles.  (Once you have a technology, there is no problem to
produce a weaker (ie smaller) version.	Missles don't need as much
propulsive energy as a ship does.  Very easy.

DOnald Hosford