“Preliminary evidence and analysis conducted to date points to a probable turbopump-related failure in one of the two Aerojet Rocketdyne AJ26 stage one main engines. As a result, the use of these engines for the Antares vehicle likely will be discontinued,” the statement says.
US company Aerojet Rocketdyne manufactures AJ26 engines, modifying them for the US rocket on the basis of NK33 engines developed by leading Russian rocket engine producer Kuznetsov.
Russia specialists insist that the US company which has implemented modifications to the AJ26 engines and its customers should bear all the responsibility for the accident.“The development and certification of all the new systems was carried out by the US side without involving JSC Kuznetsov specialists,” the Samara-based Russian company said in a statement.
NK33 engines were produced in the 1970s for the N-1 heavy lift rocket, which was intended for the Soviet lunar program but failed to undergo tests and was not ever used.
Aerojet Rocketdyne purchased several such engines a few years ago to be adapted for US rockets.
Prior to being mounted to Antares, each engine undergoes several control tests. In May, AJ26 engine suffered a failure but Orbital Sciences confirmed that the engines were reliable and previous Antares launches, including with Cygnus cargo freighter, were successful.
The Antares rocket exploded immediately after liftoff from the Wallops Flight Facility in the Atlantic, in Virginia, on October 28. It was expected to put in orbit the Cygnus cargo vehicle carrying supplies to the International Space Station (ISS).
The $1.9 billion contract between NASA and Orbital envisions five resupply flights of Cygnus to the ISS. Two previous launches were successful. Since last year, NASA has been also using Dragon capsule developed by SpaceX. The cargos are also delivered by Russian Progress spaceships and European ATV freighters.