SD 142 Assignment

Return from Salyut
  1. Why didn't the cosmonauts in the Salyut capsule have suits?

    2. 2 marks

    The capsule was being used for 3 cosmonauts instead of the 2 it was designed for. This is an example of a system being used outside of its design parameters.
  2. Why were the cosmonauts unable to close the valve?

    3. 2 marks

    It required more turns than were physically possible to execute under conditions of lost oxygen. The designers of the valve had not taken into consideration its conditions of use.

    Consideration of conditions of use is the key element in answering this question.

     

  3. Break down the valve closing situation in Return from Salyut in terms of Norman's Human Action Cycle.

This would be worth 16 marks. One for each stage and one for the explanation of that stage.

Goal: Restore oxygen to the capsule. Stop oxygen leak would also be acceptable.

Intention: Close the valve.

Sequence of Actions: Turn the valve.

Execution of Actions: Physically turning the valve

World: Valve turns and each turn closes it further.

Perceive state of the world: Visual change in valve control, feel of valve turning

Interpret: valve has turned

Evaluate: Has valve turned enough to stop oxygen leak? No.