Path: utzoo!attcan!uunet!husc6!bbn!bbn.com!jallred
From: jallred@bbn.com (John Allred)
Newsgroups: sci.space.shuttle
Subject: Re: shuttle landing sites
Message-ID: <32504@bbn.COM>
Date: 18 Nov 88 21:42:19 GMT
References: <2137@aplcomm.jhuapl.edu> <5590@ecsvax.uncecs.edu> <794@hadron.UUCP> <5157@polyslo.CalPoly.EDU> <2349@ssc-vax.UUCP> <1144@orion.cf.uci.edu> <434@geovision.UUCP>
Sender: news@bbn.COM
Reply-To: jallred@vax.bbn.com (John Allred)
Organization: Bolt Beranek and Newman Inc., Cambridge MA
Lines: 23

In article <434@geovision.UUCP> alastair@geovision.UUCP (Alastair Mayer) writes:
>As for dumping fuel for emergency landings, the problem can hardly
>be the weight on gear or runway -- after all, the thing has already
>been taxiing around with a full load before it took off!

The problem *is* weight on the gear -- the gear has to take the stress of 
all that weight coming down at > 3 ft/sec, which is much more strenuous that
taxiing around with the same weight.  Lowering the mass that the brakes have
to stop is a secondary reason.

The ultimate in weight reduction for landings is the F-14 Tomcat.  The F-14
can take off with 6 Phoenix missiles (at one million dollars a copy.)  However,
it can only land with 3 (carrier landings occur at 10 ft/sec vertical
speed).  So, if a Tomcat takes off with 6 Phoenixs, and doesn't shoot any,
3 million dollars of the taxpayer's money goes in the ocean.

Needless to say, Tomcats don't load up with 6 Phoenix missiles very often.
____
John Allred
BBN Systems and Technologies Corp.
(jallred@bbn.com)

A truly wise man never plays leapfrog with a unicorn.