Training for Manual Descent on a Soyuz

CSA Astronaut Chris Hadfield undergoes a manual entry simulation test in the centrifuge. June 1, 2012. (Credit: CSA)

One of the most often-cited challenges for astronauts in the Soyuz Simulators consists of rendezvous and docking scenarios. Instructors continually introduce new contingency situations and system malfunctions into the simulations to challenge their students. These scenarios ensure that good operational skills and tight crew coordination are present for any real flight event.

Manual Descent

Under ideal end-of-mission situations, an automatic re-entry system will return the Soyuz vehicle and crew from space safely back to the ground. However, the crew must be familiar with the several backup modes that exist in instances when the automatic system fails. One of the backup re-entry modes is the crew themselves! For certain hardware and software malfunctions, the crew will be required to manually fly the Soyuz back to Earth through the atmosphere.

CSA Astronaut Bob Thirsk learns how to fly the Soyuz spacecraft by training in a Soyuz Simulator. (Credit: CSA)

To do this, cosmonauts use a hand controller that varies the aerodynamic lift on the capsule. Their objective is to manipulate the lift forces on the Soyuz descent module such that they will land as close as possible to the designated site where the recovery team will be waiting for them.

It is not difficult to land the vehicle accurately at the designated landing spot if the crew did not have to pay attention to g-load. However, very high g-loads are a danger to the cosmonauts, so they must be avoided.

On the other hand, manipulating the lift forces on the vehicle so that the crew is exposed only to low g-forces would mean that they might land tens or hundreds of kilometres away from the waiting helicopters. Therefore, the trick of manual re-entry is to balance these two considerations (landing accuracy and g-force limits) and pilot a manual descent that is as accurate as possible, but at the same time not too uncomfortable for the crew. It takes many hours of practice to get it right.