The hull of the manned spacecraft Soyuz MS-09 was damaged on the ground, most probably, at the industrial plant that made it (space rocket corporation Energia), because drilling the hole on board the ISS in a situation of zero gravity would hardly possible, if at all, a member of the K.E. Tsiolkovsky Russian Academy of Cosmonautics, Alexander Zheleznyakov, told TASS.

"Why should any of the crew try to do that? I would not like to use the word nonsense, but all this does not fit in well with logic," Zheleznyakov said, when asked if any of the ISS crew might have made the hole in the spacecraft’s hull. "Judging by what I saw on the photos, it must have been done on Earth. The hole is in a place that is very hard to get to. Drilling it would not be easy."

"At Baikonur the spaceship is tested for leaks. It is examined by the manufacturer. Most probably all had happened at the manufacturer’s plant. A hole that has been patched up with glue is hard to detect. The glue was strong enough and the hole not very big. The test for leaks was passed. There was no chance for electronic equipment to spot anything, either. Most probably, a worker drilled a wrong hole and then patched it up and then either avoided telling anyone or those he had informed preferred to keep quiet, too," Zheleznyakov said, adding that theoretically, a situation where several people knew about the incident was a possibility.

Roscosmos chief Dmitry Rogozin earlier said the Soyuz MS-09 spacecraft, attacheds to the ISS, had been damaged from the inside and the space rocket corporation Energia was proceeding with inquiries to identify those responsible. Various versions were being considered, but the impact of a meteorite had already been ruled out. Investigation is in progress into who had access to the spacecraft, what manipulations and works were performed, and who supervised them, Rogozin said.

On August 30, instruments registered falling atmospheric pressure inside the ISS. The crew examined the compartments of the station and the spacecraft docked to it one by one to expose a two-millimeter hole in the hull of the Soyuz MS-09 spacecraft. In the evening of the same day it was patched up with several layers of epoxy resin. The air pressure on board the ISS returned to normal. On August 31, the crew reinforced the patch.