In aircraft accidents, a significant number of fatalities are caused by the effects of fire. A well known fire catastrophe was the Swissair flight 111 accident at Peggy's Cove, Nova Scotia, Canada, on 2 September 1998, leading to the death of 215 passengers and 14 crew members. Investigations revealed that the fire developed between the fuselage and the passenger cabin, involving the insulation in the propagation of the fire.
In order to prevent such fire catastrophes in the future, a new test method, the "Burnthrough Resistance Test", was developed by the US Federal Aviation Administration FAA for determining the fire behaviour of insulation materials in the lower part of the fuselage. The Burnthrough resistance test was published in the USA FAR regulations under Appendix F to FAR 25: "For airplanes with a passenger capacity of 20 or greater, manufactured after September 3, 2007, thermal/acoustic insulation materials installed in the lower half of the fuselage must meet the flame penetration resistance requirements of § 25.856 of this chapter".
The fire source is the kerosene burner already in use for aircraft seating. The heat output of the burner towards the test specimen is 125 kW/m². No flame penetration is allowed for 4 min and the heat flux at the backside of the specimen must not exceed 22.7 kW/m² at a distance of 30 cm.
Only materials with very high fire safety levels pass the Burnthrough Resistance test. They will help to avoid such catastrophic fires in the future.
