Successful rocket engine ground-test firings have taken Space Exploration Technologies and Orbital Sciences a step closer to filling their roles as key private-sector launch contractors to NASA.
SpaceX achieved a 3.5s firing of its Falcon 9 rocket's nine Merlin first-stage engines in preparation for an April maiden flight. Orbital is looking forward to verification and acceptance testing of its Taurus II rocket's AJ26 engines at NASA's Stennis Space Center in Mississippi beginning in April, paving the way to a first flight in 2011.
Falcon 9 and Taurus II are both crucial elements in NASA's plan to sustain service to the ISS following its retirement later this year of the Space Shuttle fleet.
© Space Exploration Technologies
SpaceX achieved a 3.5s firing of its Falcon 9 rocket's nine Merlin first-stage engines
The 13 March test at SpaceX's Cape Canaveral Space Launch Complex 40 site followed an aborted attempt four days earlier in which a ground-based helium feed valve for the engines' start-up routine did not activate, leading to a shutdown at T-2s.
For the 13 March test, the pad water deluge system was activated just before engine ignition to provide acoustic suppression to keep vibration levels within acceptable limits. The test validated the launch pad propellant and pneumatic systems as well as the ground and flight-control software.
SpaceX founder and chief technology officer Elon Musk said of the aborted test: "What we are going through 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."
Orbital's milestone came in Samarra, Russia, where testing of the Energomash NK-33 engine - which was the engine design for Russia's N-1 Moon rocket and on which Taurus II's AJ26 first-stage engine is based - demonstrated a "hot-fire" duration equal to two times a normal Taurus II acceptance testing and launch profile duty cycle.
The engines are being supplied to Orbital by Aerojet and its Russian partner, United Engine/SNTK, which achieved more than 600s cumulative burn duration in three tests.
The first Falcon 9 flight will orbit a qualification example of the Dragon capsule designed by SpaceX to carry cargo and crew under a $1.6 billion NASA contract. SpaceX plans three ISS cargo transport-related demonstration flights this year.