Kerosene fuelling completed at 01:30. Upper stages Block G and D were fuelled between 04:00 and 05:00. They were allowed to reach thermal equilibrium between 05:00 and 06:15. Between 06:45 and 07:55 all lines and umbilicals were removed from the vehicle. The tower was rolled back at 08:15. Launch was on schedule at 09:00. All was normal to T+50 seconds. Centre engine shutdown at T+94.5 seconds was normal. All was normal at T+100 seconds. Then at T+110 seconds all transmissions from the vehicle suddenly ceased. An examination of telemetry showed that the vehicle catastrophically disintegrated at T+106.94 seconds, only 7 seconds before the end of the stage one burn and separation of the second stage. Later it would be alleged the cause was a failure of the oxidiser pump in engine 4. Kozlov, Kuznetsov, and Dorofeyev all blamed the other for the failure.