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[i]The valve that didn't actuate is the ground side isolation valve to release ground supplied high pressure helium to start the first stage engine turbopumps spinning at several thousand rpm. Once that happens it generates enough pressure to start the gas generator, which is a small rocket engine that powers the turbopump. There are no vehicle side valves actuated for spin start (just check valves), so it is an all engines or none situation.
The problem was pretty simple: our autostart sequence didn't issue the command to the normally closed ground side isolation valve. We had tested everything on the vehicle side exhaustively in Texas, but didn't have this iso valve on our test stand there. Definitely a lesson learned to make sure that *everything* is the same between test stand and launch pad on the ground side, not just on the vehicle side.
Ignition fluid (TEA-TEB) flowed nominally to all engines creating the green flame and the main valves opened, but no engines actually started and the system automatically aborted on lack of spin. The fire generated was from flushing the system of fuel and LOX from the open mains. No damage to the vehicle or ground systems and no other anomalies that need to be addressed. If all goes well, we will try the static fire again in the next few days. Right now, we are holding due to extreme weather. It is raining sideways at 46 mph and tornados have been spotted just north of the Cape.
It is important for readers/viewers to appreciate that what we are going through right now is the equivalent of "beta testing". Problems are expected to occur, as they have throughout the development phase. The beta phase only ends when a rocket has done at least one, but arguably two or three consecutive flights to orbit.[/i] In related news, from Spaceflight Now: [i]SpaceX is planning April 12 as their new launch date on the Eastern Range, according to the Air Force. The launch window would be between 11 a.m. and 3 p.m. EDT. But the new launch date is still pending Air Force approval.[/i][/B][/QUOTE]
[i]SpaceX is planning April 12 as their new launch date on the Eastern Range, according to the Air Force. The launch window would be between 11 a.m. and 3 p.m. EDT. But the new launch date is still pending Air Force approval.[/i]
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