International Aircraft Fire and Cabin Safety Research Conference

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International Aircraft Fire and Cabin Safety
Research Conference Lisbon November 2004

• Cabin Water Mist Benefit Study

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Cabin Water Mist Benefit Study

• The benefit analysis was carried out on behalf of
  the FAA to derive the life saving potential of
• Cabin Water Mist systems
• Cabin Water Mist systems installed on aircraft
  configured with Enhanced Fuselage Burnthrough
  Protection.

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Water Mist Benefit Study

• Two configurations of Cabin Water Mist system
  were considered
• A Modular system consisting of three separate
  water supplies located in the front, mid and rear
  sections of the fuselage activated only in the
  areas affected by fire.

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Water Mist Benefit Study

• Two configurations of Cabin Water Mist system
  were considered

• A Singular system having only one source of
  supply located in the centre section of the
  fuselage

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Water Mist Benefit Study

• not work if the fuselage was inverted
• not work in flight
• not significantly affect the vision of occupants
• use on-board dedicated water supplies
• activate automatically on the identification of
  a fire
• operate for three minutes
• have design features to ensure that they had the
  greatest chance of operating should the fuselage
  break

• All systems would

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Water Mist Benefit Study

• Benefits are based on the number of lives saved
  for western-built aircraft type certificated for
  more than 30 seats and are relative to the period
  1967 to 1996.

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Water Mist Benefit Study
The effects of fire and evacuation related
requirements that were introduced after the
accident date have also been taken into account.
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Water Mist Benefit Study

• DATA SOURCES
• The Cabin Safety Research Technical Group
  Accident Database was used as a basis for the
  selection and analysis of accidents supported by
  Accident Reports published by the National
  Investigating Authorities.

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Water Mist Benefit Study

• ANALYSIS
• The Analysis was carried out on 136 fire related
  fatal accidents having sufficient data available
  to determine benefit

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Water Mist Benefit Study

• Predictions of potential life saving were made
  for each accident taking into account
• The number of occupants injured as a result of
  the impact
• The location of any breaks in the fuselage
• The level of damage to cabin interior and
  fuselage skin (for Cabin Water Spray performance)

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Water Mist Benefit Study

• Predictions of potential life saving were made
  for each accident taking into account
• The characteristics of the fire
• The fire entry points
• The number and position of useable exits
• The hazard presented to evacuees from external
  fires
• The time taken for the Crash Rescue Teams to
  arrive

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Water Mist Benefit Study

• Best estimates of the potential life saving for
  each accident were made together with the
  possible range.
• Having completed the assessments for each
  accident the Monte Carlo process was used to
  assess the best estimate of the average
  proportion of occupants saved

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Water Mist Benefit Study

• METHODOLOGY
• Average Proportion of Occupants Saved per
  Accident f
• Average Number of Accidents per year yielding
  Benefit n
• Average Number of Occupants P
• Correction Factor for accidents for which
  insufficient information exists to predict
  benefit c
• Benefit f x n x P x c

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Water Mist Benefit Study
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Water Mist Benefit Study
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Water Mist Benefit Study
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Water Mist Benefit Study