Tutorial 8: Case Study

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Tutorial 8Case Study

• Tiger Shark
• Never Cry Wolf
• SY DE 142 July 19, 2004
• Introduction to Human Systems Engineering
• Waterloo, Ontario, Canada

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Case Study 1Tigershark

• Place Newfoundland, Canada
• Time May 14, 1985
• Result
• David Barnes became incapacitated from the
  brain-tissue hypoxia experienced during his final
  high-g maneuver.
• Plane crashed, instantly killing test Pilot

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Tigershark Questions

• Was the pilot experienced enough for these
  manoeuvres? Justify your answer.
• Why did the crash happen?

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Tigershark Solutions

• On the Yes side
• The pilot had done the manoeuvre 60 times before.
  
• He understood that the task was physically
  challenging and that the plane could exceed his
  physical limits.
• He had flown 120 combat missions on a variety of
  aircraft.
• The pilot had flown under conditions of g-induced
  hypoxia before.

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Tigershark Solutions

• Evidence on the No side would be that
• None of the planes that he had experience on
  matched the power of the Tigershark.
• The pilot may not have understood the effects of
  his fatigue brought on by practicing the
  manoeuvre.
• The pilot may not have understood the
  physiological effects of repeated high g
  manoeuvres.
• The pilot had not training in anti-g breathing
  techniques.

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Tigershark Solutions

• 2. The crash happened because the plane was
  capable of flying beyond human physical
  limitations.

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Case Study 2Never Cry Wolf

• Time Mid-July morning
• Place Womens prison in Oregon, US
• Result
• Escape of a murderer from the prison

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Never Cry Wolf Question

• Use the Human Machine System (Human Interface
  Model) to Describe why the murderer could escape
  the prison?

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Never Cry Wolf Solution

• Guard SS Interface Security System
  World
• alarm
• Guard became desensitized by the multiple false
  alarms of the past weeks, because
• 2 critical pieces of feedback dont match
• State of Security System with State of World