The failure of a Volna rocket on 21 June during the launch of the Cosmos 1 solar sail was caused by a premature shut-down of the first-stage engine after firing for 82.86 seconds instead of the expected 100 seconds, the failure review board concluded in July.

The shut-down was the consequence of a "critical degradation in operational capability of the engine turbo-pump," the board said in its report to the Russian space agency, Roskosmos. It said that there was sufficient telemetry data from the launch vehicle to determine the cause of the failure.

The board also came to the conclusion that the first and second stages never separated and, as a result, the Cosmos 1 orbit insertion motor did not fire, and the spacecraft did not separate from the third stage. The launch vehicle's on-board control system automatically aborted the mission 160 seconds into flight. Payload and rocket likely fell into the Barents Sea a few hundred kilometers east of the launch area.

The review board included members from the Makeev Rocket Design Bureau, the Lavochkin Association (which built Cosmos 1) and Tsniimash, a lead engineering centre of Roskosmos.

The US$4 million Cosmos 1 solar sail vehicle had a mass of about 110 kg. It was designed to be propelled by eight 15-m-long sail structures resembling the blades of a windmill.

See also:

• Volna (2001-07-19)

Launch Failures Chronology