Product Design for Safety in Aviation

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Product Design for Safety in Aviation

• The Quality Colloquium
• August 21, 2007
• Quality Lessons from Other Industries Panel

Jim Bouey Boeing Commercial Airplanes (retired)
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Commercial AviationA Challenging Start to the
Safety Journey

• NOW
• (2006)
• 19.5 million flights worldwide
• 7 million North American flights

THEN (1950s) 2.7 fatal accidents per million
flights
1950s safety performance impact on 2006
operations 1 fatal accident each week worldwide
RE-112
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Commercial Aviation Long History of Safety
Performance Improvements
North American accident rate (accidents per
million departures)
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Commercial Aviation Safety Performance Enablers

• Safety Culture
• Shared Destiny
• Dual Assignments
• Leadership
• Structured, System-Based Processes

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Commercial AviationMindset

• Make it fail-safe

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Commercial AviationOverarching Safety Philosophy

• Assume that no matter what you do, something or
  someone will fail.
• Now, what do you have to do to make sure that
  everyone stays safe?

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Commercial AviationAircraft Design Philosophy

• Design it to operate safely under normal
  circumstances.
• Design it to operate safely with any possible
  failure.
• Design it to be survivable if there is a crash.

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Commercial AviationFail-Safe Design

• Designed-in margins to protect for unknowns and
  failures
• Structure
• Find the worst case loading condition ever to be
  expected, then design the structure to be able to
  carry 50 more load than that
• Design the structure so that even after a
  principle element has failed, the remaining
  structure can handle the worst case loading ever
  to be expected

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Commercial AviationStructure
Typical fuselage panel
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Commercial AviationFail-Safe Design

• Designed-in margins to protect for unknowns and
  failures
• Systems
• No single failure can have catastrophic
  consequences
• Hazard consequences of multiple failures must be
  inversely proportional to the probability of
  their occurring

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Commercial AviationSystems
Redundant lateral flight control system
surfaces
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Commercial AviationFail-Safe Operations

• Designed-in margins to protect for unknowns and
  failures
• Performance
• Determine the inherent flying capabilities of the
  airplane, then limit the operational use to
  retain significant margins to those capabilities

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Commercial AviationPerformance
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Commercial AviationFail-Safe

• Assume that something or someone will fail in
  everything you do (design, build, operate,
  maintain)
• Now what is going to keep everyone safe?

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Commercial AviationFail-Safe

• People are protected when failures occur because
  products, processes, and procedures are designed
  to mitigate the failures and prevent the threats
  from endangering people.
• Will this approach be useful in healthcare?