🚀 go-pugleaf

On Wed, 6 Jan 1993 18:22:52 GMT, henry@zoo.toronto.edu (Henry Spencer) said:

HS> In article <1993Jan5.234659.7819@ee.ubc.ca> davem@ee.ubc.ca (Dave Michelson) writes:
>>Plus the 747 airframe, crew, and modifications.  One could not expect
>>the carrier aircraft to survive a launch of orbiter from its back.
>
>Even the X-15 didn't light its engine until *after* separation from the
>carrier aircraft.      

HS> There are missiles which fly off their launch rails under power, rather
HS> than delaying ignition until after separation.  Admittedly, a delay is
HS> usually considered safer.

For an example on the NB-52B, the HiMAT (a supersonic RPRV) took
off with its J79 engine running.  The fuel tank was kept topped
up from a tank in the pylon until shortly before launch.

As I recall, they used JP-5 instead of JP-4 for this because of 
the "hot refueling" on the wing of the NB-52B.  JP-5 is markedly
less volatile than JP-4.

The NB-52B pilots did not notice the thrust of the ninth engine.
--
Mary Shafer  DoD #0362 KotFR NASA Dryden Flight Research Facility, Edwards, CA
shafer@rigel.dfrf.nasa.gov                    Of course I don't speak for NASA
 "A MiG at your six is better than no MiG at all."  Unknown US fighter pilot