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SSRT: Space Access Update no. 64 (DC-XA flight 1!)

>Return-Path: chrisj@mail.utexas.edu
>From: "Chris W. Johnson" <chrisj@mail.utexas.edu>
>To: "Single Stage Rocket Technology News" <ssrt-news@zimbazi.cc.utexas.edu>
>Subject: SSRT: Space Access Update no. 64 (DC-XA flight 1!)
>Date: Tue, 21 May 96 04:15:51 -0600
>Sender: listserv@zimbazi.cc.utexas.edu
>X-listname: <ssrt-news@zimbazi.cc.utexas.edu>
>Date: Tue, 21 May 1996 22:07:50 -0700 (MST)
>From: Donald Doughty <doughtd@pr.erau.edu>
>To: DC-X <delta-clipper@world.std.com>
>Subject: Space Access Update #64 5/18/96 (fwd)
>Reply-To: delta-clipper@europe.std.com
>Subject: Space Access Update #64 5/18/96
>                    Space Access Update #64  5/18/96 
>                     DC-XA's First Flight Completed 
>             Vehicle Takes Minor Damage In Post-Flight Fire 
>                 copyright 1996 by Space Access Society
>Saturday, May 18th, 1996 - The DC-XA single-stage rocket experimental 
>vehicle flew this morning for the first time since its handover to NASA 
>last year and major rebuild over the winter.  The test took place at the 
>same White Sands Missile Range, New Mexico site the original DC-X made 
>its eight flights from.  This first post-rebuild flight had originally 
>been scheduled for Friday, but was delayed 24 hours by a faulty sensor 
>on one of the vehicle's four RL-10-a5 rocket engines.  This morning's 
>flight was a minimal test-hop, 800 feet up from the launch stand, then 
>350 feet sideways to over the landing pad, then a vertical descent and 
>landing, total flight time of about a minute.
>The flight went as planned until the final landing phase, when the DC-XA 
>descended the last few feet onto the concrete landing pad more slowly 
>than expected.  This final descent phase has been the object of ongoing 
>tweaking dating back to the last several flights of the original DC-X.  
>The target touchdown velocity is around four feet per second; previous 
>touchdowns have varied from two feet per second to as high as fourteen 
>feet per second - that last due to an invalid data problem with a radar 
>altimeter rather than the landing control software, however.
>The problem with slow landings is that the vehicle sits in the backwash 
>from the rocket engines too long, and the base of the vehicle can suffer 
>heat damage.  There is some thought being given to landing the potential 
>followon to DC-XA (if McDonnell-Douglas wins the X-33 competition) on an 
>open grid of some sort to reduce backwash, but meanwhile DC-XA lands on 
>a plain concrete slab, and slow landings can cause problems.
>This morning's slow landing apparently started a small fire on the 
>exterior of the vehicle.  According to McDonnell-Douglas sources, the 
>fire was promptly extinguished, and the vehicle has been de-fuelled and 
>moved back to its launch stand in the normal manner.  One of the 
>vehicle's four body-flaps (hinged square control surfaces, one on each 
>side of the conical vehicle near its base) was damaged and will have to 
>be replaced.  We're told there is no other obvious damage, but the 
>structure around that body flap will be carefully inspected for possible 
>heat damage.  The DC-XA engineering/flight-test team will be looking 
>into that and into why this landing was slow over the next few days, 
>then implementing fixes.  
>There's no telling at this point whether this will push back the next 
>planned flight dates of June 7th and 8th, but our first guess would be 
>that those will slip by a week or two. We'll likely know more in a few 
>days, though. 
>A quick bit of editorializing: Discovering and fixing this sort of 
>problem is exactly why we test-fly experimental vehicles.  Fly a little, 
>see what breaks, figure out why, fix it, fly a little more.  We look 
>forward to the DC-XA crew discovering, and solving, more problems as 
>this summer's test series continues.
>                                  *end* 
+                                                                             +
+  Weave a circle 'round him thrice, and close your eyes with holy dread...   +
+                                                                             +