[net.columbia] Updated Engine Abort Sequence

alb@alice.UUCP (Adam L. Buchsbaum) (06/27/84)

NASA this afternoon corrected the statement that Engines
3 and 2 fired, Engine 1 had the problem, and 3 and 2 then
shut down.  What happened was this:

The firing sequence is (in order) Engine 3, then 2, then
1, at 120 millisecond intervals.  The primary hydrogen fuel
valve for Engine 3 never opened; thus, Engine 3 never ignited.
Engine 2 ignited for a brief time and was shut down by the
computers.  Engine 1's ignition was never started (due to the
shutdown order).  Thus, only one engine (Number 2) actually
fired this morning.