In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org writes:
On Sun, 13 Jun 2004 22:07:17 -0700, Mary Shafer
wrote:

However, he did fly in a NASA project in support of X-20,
mimicking the RTLS escape sequence for the X-20 if the rocket had a
problem on launch and the X-20 had to set itself free and land.

...Details! Details! Aunt Mary, tell us a bedtime story about this
one, PLEASE!!! :-) :-) :-) :-)

The Dyna-Soar abort tests used one of the Douglas F5D Skylancers.
They modified teh aircraft to reduce the thrust at FLight Idle from
500# to 200#, to better match the X-20's L/D ratio (By opening the AB
nozzle fully, thereby over-expanding the jet exhaust.)

The profile was a fast low level run, pulling up to the vertical over
teh notional launch pad. THese conditions were typically 500-530 Kts at
1,000'pulling 3.5 - 3.6 G for a nominal Jigh Energy Abort Motor, and
400 Kts/1,000' pulling 4.5G for a Low Energy Abort Motor simulation.
This would intercept the expected conditions for the X-20's abort
motor burnout at, about 400 Kts/9.500' (High Energy rocket motor), or
325 Kts/5,000' (low energy motor. The F5D was "dirtied up", extending
the speedbrakes and gear. and opening the AB nozzle to reduce idle
thrust, at the top of the climb. (190 Kts/15,000', High Energy case,
155 Kts/8,000' Low Energy case). A no-power added landing approach
was flown to a position on the Edwards Lakebed corresponding to teh
location of the Skid Strip at Cape Canaveral.
(Who says test flying is stoogig about taking data points!) For some
of the flights, teh windshield and canopy of the airplane was
restricted to duplicate the fields of view from teh X-20 cockpit.
This was done by applying a transparent yellow film to the canopy, and
using a blue-tinted visor on the pilot's helmet. (That way, if full
vision was needed, you just had to flip up the visor).

The whole thing was written up in NASA Technical Memorandum
NASA-TM-X-637, "Flight Simulated Off-the-Pad Escape and Landing
Maneuvers for a Vertically Launched Hypersonic Glider",
Gene J. Matrange, William H. Dana, and Neil A. Armstrong,
March 1962
Not currently available on-line, but the entire Tech Memorandum has
been duplicated in
"Dyna-Soar", Robert Godwin, Compiler & Editor,
Apogee Books, Burlington, Ontario, Canada, 2003, ISBN 1-896522-95-5

(Note to LaDonna, et alia: That's what a reference and attribution
looks like)

I've been "flying" similar profiles (In the Mighty Wurlitzer) for
David Sander's Saturn Shuttle as defined in _Man_Conquers_Space_.
It's tone of fun.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster