On Mon, Mar 15, 2021 at 3:59 AM roxanna Mason
<rocketmaster.ken@xxxxxxxxx> wrote:
And FWIW some history, me along with 3 other Truax Engineering reps were
invited to that launch at Vandenberg AFB. They made one fatal error, they
didn't incorporate a trickle purge at the head end of the motor where
frost/ice condensed on the LOx valve which was a ball valve with a venturi
conture that froze the ball. When commanded to open the ball rotated approx
10-20% allowing just enough LOx to flow for an ignition but slow burn which
didn't have enough thrust to lift the rocket but instead burned up the tail
end supporting the rocket which collapsed the rocket on its side and burned
up, as William pointed out. The irony was that in the Mojave desert where all
the static testing was done had such low humidity that frost was never a
problem. This problem should have been anticipated though but wasn't. A
trickle purge should always be used with the motor open to the elements.