Path: utzoo!dptcdc!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!sunybcs!fredonia!behr8762
From: behr8762@fredonia.UUCP (Mike Behr)
Newsgroups: sci.space.shuttle
Subject: Shuttle Payload Capacity
Keywords: Engine Capacity
Message-ID: <1521@fredonia.UUCP>
Date: 17 Apr 89 06:06:47 GMT
Reply-To: behr8762@fredonia.UUCP (Mike Behr)
Organization: State University College, Fredonia, N.Y.
Lines: 26


The Challenger mishap has brought about added safety features to the
space transportation system (ie. revamped Solid Rocket Boosters, crew
escape system  using an escape pole, etc.).  This, no doubt, has cut the
shuttle's maximum payload capacity from 65,000 pounds to around 55,000
depending on the orbiter (Columbia being the oldest and heaviest of the
fleet probably is even more limited in regards to its payload).
     The shuttle main engines during flight are used at 104% rated thrust.
I understand the maximum rated thrust is 109% (correct me if I'm wrong)
but have not to my knowledge been throttled to 109% since the shuttle has
been operational.  Does anybody know why - is it because the engine
hardware will be pushed to their limits increasing the chances of
catastrophe???  Anyway, say that sometime in the future the space shuttle
main engines (SSME's) will be flight certified to run at 109%, will this
increase the payload capacity, if so by how much - maybe back to past
levels??  I wonder if NASA should devote the resources to more powerful
and efficient main engines rather to a new more expensive and possibly
risky generation of solid or even liquid boosters to replace the ones
presently used.


-- 
*NIXON'S THEOREM:********************** Mike Behr *****************************
*  The man who can smile when things    decvax!sunybcs!fredonia!behr8762      *
*  go wrong has thought of someone      behr8762@snyfreba.bitnet              *
*  that he can blame it on.             fredonia!behr8762@joey.cs.buffalo.edu *