Evaluation of a Halon 1301System for Aircraft Internal Protection from a Postcrash External Fuel Fire.

摘要

The use of a Halon 1301 fire-suppression system was evaluated in regard to increasing occupant escape time during a ground crash situation with an external fire adjacent to a cabin opening. Tests were conducted in a DC7 fuselage, varying the exit configurations and external wind conditions. Tests were also conducted using a curtain to compartmentize the cabin, with the Halon 1301 concentration and location of discharge being varied. Smoke, Temperature, carbon monoxide, oxygen, and Halon 1301 levels were continuously monitored during the tests at various locations throughout the cabin. Hydrogen fluoride (HF) and hydrogen bromide (HBr) concentrations were obtained by analyzing samples taken from the cabin at various times. The results indicated that the length of protection from flame penetration through an opening was dependent upon external wind conditions. Flame penetration was controlled for up to 3.5 minutes with zero wind, but with a wind of as little as 2 miles per hour (mi/h), the time was reduced to less than 15 seconds. High HF levels were rapidly reached inside the cabin, with concentrations ranging from 60 parts per million (p/m), with no wind, to well over 300 p/m with 2-mi/h wind conditions. Test results also indicated that the use of a curtain to compartmentize the cabin could slow the spread of HF (15 to 20 seconds), but it does not lower the levels reached. (Author)