The collision of elements during the separation of the carrier rocket’s first and second stages is the primary cause of the Soyuz-FG booster’s abortive launch, Roscosmos Executive Director for Manned Flights Sergei Krikalyov said on Friday, TASS reports.
"There are no final versions but the primary cause is understandable and is related to the collision of a side element making part of the first stage. A collision occurred during the separation of the first and second stages," the Roscosmos official said.
"A deviation from the standard trajectory occurred and apparently the lower part of the second stage disintegrated. The rocket stopped its normal flight and after that the automatic system did its work," Krikalyov said.
An element of the booster’s first stage collided with the second stage, Krikalyov said.
"This could have been caused by the failure of the system of the normal separation, which should have been activated. We will analyze the causes in detail," the Roscosmos official said.
The dates of launches of a cargo spacecraft Progress MS to the International Space Station may be revised following the failure of the Soyuz-FG rocket. "Possibly, we may revise the date of launching the next cargo spacecraft. Possibly, we will speed up the launch of the next Soyuz. Different versions of the program are being considered," Krikalyov said.
The results of the government probe into the causes of the Soyuz-FG rocket’s failure will be available later this month, after October 20.
"The panel of inquiry got down to work yesterday. The results are expected after October 20. The first components found in Kazakhstan’s steppe will help find out what happened. The necessary measures will be taken afterwards and flights will be continued," Krikalyov said.
He added that all rockets of this class will be authorized for use again only when the causes of the failure were clear.