Soyuz TMA-12M final trajectory correction to take place this night
MOSCOW, March 26, /ITAR-TASS/. The Soyuz TMA-12M spaceship with a Russian-American crew will carry out a third, and final, trajectory correction this night in order to ensure its successful docking with the International Space Station (ISS) on March 28, the Mission Control Centre said on Wednesday, March 26.
Trajectory correction manoeuvres will be executed using the spaceship’s engines. “Two such manoeuvres were made today successfully. A third one will take place this night. It will be the final one,” the Centre said.
“All manoeuvres are executed automatically. They will not be needed when the ship comes close to the station and the Kurs rendezvous and docking system takes over. It will dock the ship in automatic mode,” the Centre said.
The Soyuz carrier rocket with the spaceship Soyuz TMA-12M carrying a new resident crew to the ISS blasted off from Baikonur at 01:17 Moscow time. Alexander Skvortsov and Oleg Artemyev of Russia, and Steven Swanson of NASA will work aboard the ISS for about five months.
The ship was initially supposed to dock with the ISS in six hours after the liftoff, at 07:04 Moscow time. However the docking was postponed and the ship was sent on a two-day rendezvous manoeuvre.
A two-day delay in the docking of the Soyuz TMA-12M spaceship with the International Space Station (ISS) might have been necessitated by additional system checks, a space industry expert told ITAR-TASS on Wednesday, March 26.
“The docking might have been delayed because there was no certainty that everything was going smoothly. It might have been stopped for additional system checks. No one wants to put people aboard the ship at risk,” the official said. “It may not necessarily have been some malfunction, but this may have raised some suspicions among specialists. If they are not certain, they will delay [the docking],” the expert said.
He noted that a ship was usually taken to orbit automatically, with the Mission Control Centre specialists monitoring the parameters. “Some of the specialists might not have liked the ship orientation parameters. After that the Centre cancelled the third command to the Soyuz thrust engine. Otherwise, if the command had been given to the disoriented craft, it could have been propelled into the wrong orbit,” the expert said.
He stressed that the crew would have been brought back to earth in case of real danger.
The Federal Space Agency (Roscosmos) will finish the investigation into the malfunction of the Soyuz TMA-12M spaceship’s attitude control system on March 27, an informed source told ITAR-TASS.
The switchback from the fast-track six-hour rendezvous with the International Space Station (ISS) to the standard two-day procedure has been preliminarily blamed on a software hitch as a result of which the engines were not ignited the third time. “This is the main lead,” the source said, adding that the ship was scheduled to dock with the ISS at about 04:00 Moscow time on March 28.
Soyuz is now on the way to the ISS. The crewmembers are feeling well and busy doing their routine work, Mission Control Centre Head Sergei Krikalev said. They have enough water and food, and the ship has a sufficient supply of fuel to make a two-day flight before docking with the ISS where they are awaited by Mikhail Tyurin of Russia, Koichi Wakata of Japan, and Richard Mastracchio of NASA.