Just days after the successful full mission-length test firing of the nine-engine first stage of Falcon 9, Space Exploration Technologies Corp. (SpaceX) marked another significant advance with the performance of its smallest rocket engine, Draco. Known as a "thruster," the new engine fired continuously for ten minutes in a specially constructed vacuum test chamber that simulates the space environment. After a ten-minute thermal soak period, Draco was restarted for an additional minute, simulating its typical use in space.
Performed at the SpaceX Texas Test Facility outside McGregor, this marks the longest firing of the Draco thruster, as well as the longest test on the new vacuum test stand, built by SpaceX and first put into operation in March 2008.
"Draco performed perfectly during the entire test, with expected temperatures and excellent performance," said David Giger, Propulsion Manager, SpaceX. "We also broke the SpaceX record for longest continuous burn previously held by Kestrel, the Falcon 1 second stage engine."
SpaceX's Dragon spacecraft uses a total of 18 Draco thrusters for maneuvering, attitude control, and to initiate the capsule's return to Earth.
"The Draco engines are as important to Dragon as the large Merlin engines are to Falcon 9," said Tom Mueller, VP Propulsion, SpaceX. "They will perform essential maneuvers as the SpaceX Dragon approaches and berths with the International Space Station (ISS) to provide delivery of cargo, and eventually crew transport to and from Station."
The SpaceX-developed Draco thruster generates up to 90 pounds (400 Newtons) of force using monomethyl hydrazine as a fuel and nitrogen tetroxide as an oxidizer - the same orbital maneuvering propellants used by the Space Shuttle. These storable propellants have very long on-orbit lifetimes, providing the option for the Dragon spacecraft to remain berthed at the ISS for a year or more, ready to serve as an emergency "lifeboat" if necessary.
The first Dragon spacecraft is scheduled for flight in 2009 aboard a Falcon 9 rocket from the SpaceX launch site at Complex 40, Cape Canaveral, Florida.