International Aircraft Fire and Cabin Safety Research Conference – Lisbon November 2004

International Aircraft Fire and Cabin Safety Research Conference – Lisbon November 2004 Cabin Water Mist Benefit Study

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.

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.

Water Mist Benefit Study • A Singular system having only one source of supply located in the centre section of the fuselage Two configurations of Cabin Water Mist system were considered:–

Water Mist Benefit Study • All systems would: 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

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.

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.

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.

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

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)

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

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

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

Water Mist Benefit Study

International Aircraft Fire and Cabin Safety Research Conference – Lisbon November 2004