MOSCOW. Sept 9 (Interfax-AVN) - The recent crash of a Soyuz-U rocket that was carrying the Progress M-12M spacecraft into space was caused by reduced fuel consumption in the gas generator as a result of a partial clogging of the fuel pipe, Russia's Federal Space Agency (Roscosmos) said on Thursday.
"This disrupted the engine's operations, affected its parameters and activated the system that switched off the engine," Roscosmos said in a statement.
The interdepartmental investigative commission came to this conclusion after analyzing the telemetry received from the launch vehicle.
The commission also concluded that preparations of the launch pad and the Soyuz-U rocket had been conducted in accordance with service documentation.
No problems were registered during the launch vehicle's takeoff, the flight of its first and second stages and the separation of the first two stages.
Russia's Soyuz-U launch vehicle carrying the Progress M-12M freighter lifted off from the Baikonur Cosmodrome on August 24. However, a malfunction in the upper stage's RD-0110 engine did not allow the cargo ship to reach its orbit, causing it and the upper stage to fall back to Earth.
An investigative commission, chaired by Keldysh Research Center Director Academician Anatoly Koroteyev, has established that the crash was caused by a disturbance of the conditions for the gas generator's normal functioning.
The RD-0110 engine is a four-chamber engine powered by kerosene and liquid oxygen. It was developed by the Voronezh-based Chemical Automatics Design Bureau and is intended for the upper stage of Soyuz-U, Soyuz-FG, Soyuz-2-1A and Soyuz-ST-A launch vehicles. Such engines are manufactured by the Voronezh Mechanical Plant.