The failure of an engine during a test firing last week will push back Orbital Sciences Corporation’s next launch of a cargo mission to the International Space Station by at least a week. The Antares launch of the Cygnus spacecraft, which had been scheduled for the early morning hours of June 10 from the Mid-Atlantic Regional Spaceport (MARS) in Virginia, is now planned for no earlier than June 17, the company announced Wednesday. Orbital calls the new launch date a “planning date” that is subject to change.
Orbital delayed the launch after an AJ26 engine suffered an unspecified failure during a test firing May 22 at NASA’s Stennis Space Center. The first stage of Antares is powered by two AJ26 engines, “Americanized” versions of Russian NK-33 engines provided by Aerojet Rocketdyne. The engine that failed in the test was being prepared for an Antares mission in 2015, but Orbital is holding off on the next launch while the investigation proceeds.
This mission, designated Orb-2, is the second of eight missions to the ISS under Orbital’s current Commercial Resupply Services (CRS) contract with NASA. The launch was previously planned for early May, but postponed when SpaceX’s most recent CRS mission was delayed to mid-April because of a combination of vehicle and range problems.