Defenses

Fault prevention

The fault triggering this accidence was due to unintentional selection ( slip) of the exceptional steering Control mode, which disconnected the rudder from the wheel.

Apparently, the steering lever was slip-prone .

This fault could have been prevented by adding more control to the positioning of the selector ( slip proofing ):

• Breaking the sliding line into segments, as is a common practice in modern car gears ( view demo here ... )
• Position the exceptional Control mode in between the Manual and Control positions, which were used regularly during navigation .

  Guidelines for slip-proofing

Alarming

The alarm was not set prior to the accident, because the design did not provide means to detect the exceptional situation

Alarm could have been provided, by extending the scenarios, to include:

• A primary mode set, enabling the operators to explicitly set the Navigation mode
• Rules for alarming on exceptional situations, namely, when the steering Control mode is set in the Navigation primary mode.

  Guidelines for alarm generation

Escalation prevention

This case study does not demonstrate any method for escalation prevention.

Recovery facilitation

If the hazard became obvious in time, recovery could be accomplished by changing the navigation direction, which was the intention of the captain.

Rescue facilitation

This case study does not demonstrate any method for Rescue facilitation.

Updated on 10 May 2016.