Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!att!cbnews!military
From: wb9omc@ea.ecn.purdue.edu (Duane P Mantick)
Newsgroups: sci.military
Subject: SR-71 innovations
Message-ID: <1990Oct8.220953.7541@cbnews.att.com>
Date: 8 Oct 90 22:09:53 GMT
Sender: military-request@att.att.com
Organization: AT&T Bell Laboratories
Lines: 39
Approved: military@att.att.com



From: wb9omc@ea.ecn.purdue.edu (Duane P Mantick)
>From: geoffm@EBay.Sun.COM (Geoff Miller)
>>From: texbell!letni!digi!digi.lonestar.org!user1 ("USER1")
	[...]
>>The oil is a solid at room temperature and must be heated by
>>a blow torch in order to be put in the plane.
>That can't possibly be true.  If it was, the oil would solidify in the
>engines while the plane sat between flights, and the engines themselves would
>have to be heated somehow before they could be started.  Oil doesn't have to
>be solid at room temperature in order to have the resistance to breakdown 
>necessary at high operating temperatures.  I've read quite a bit about the

All of the references I have read indicate that while the stuff isn't
actually solid at room temperature, it is gooey and stiff enough to be
useless.  I have read multiple references to oil heating being performed
and if I can locate them, I will quote them at a later date.

There are many extremely unusual things, hi-tech wise, on the SR71.  For
instance, the fuel JP7 doesn't start well (read as: at all) on its own
and must be ignited with TEB which is  (chemists help me here) tetraethylborane
or something like that.  In color photos of the startups, the green
flash that occurs first is the TEB lighting off.  On the ground, nobody
worries about the fact the the SR leaks fuel prodigiously (from the
fire hazard point of view) because it is so bloody difficult to burn
the stuff.  When the airframe heats up a bit at higher altitudes, the
thing seals up nicely.  It has been said that the heat treatment that
the titanium gets at mach 3 airflows has a tendancy to actually
strengthen the airplane, although I can't vouch for the accuracy of
that. I *do* know that I have yet to read an article in which the
number of hours on the airframes was considered to be a problem.

So I would say that as far as technology on the SR's goes, don't scoff 
at too many things.  This is, without a doubt, the single aircraft that
has stretched technology the most in one leap (at least, for aircraft
that we *know* about.....).

Duane