James D. New, Charles M. Middlesworth

A gas analyzer for evaluating aircraft fire-extinguishing systems was calibrated for use with carbon dioxide, methyl bromide and bromochloromethane. Extensive application of the analyzer in evaluating the carbon dioxide system of the XB-45 power plant provided it to be of practical value. Operation of the instrumentation flight proved satisfactory.

Charles A. Hughes

Test fires were concluded in the fire zone of a jet powerplant in order to determine the minimum amounts of fire extinguishing agents required for extinguishment under different conditions of air flow through the zone. The tests were conducted with four extinguishing agents which were discharged through conventional and experimental systems; first, with the zone in its original condition, and later, with a lining in the lower portion of the fire zone to provide a smoother flow of air.

Results indicate that the rate of airflow influenced the amount of extinguishing agent required for extinguishing of the test fires. With the lining installed, the quantity of fire extinguishing agent required was approximately a linear function of the rate of airflow. Without the lining and at the lower rates of airflow, burning fuel fell to the bottom of the nacelle and collected between the structural members or ribs. This resulted in increased extinguishing agent requirements. The results also indicate the effectiveness of each of the four extinguishing agents tested and provide a comparison between the two systems.

Wright Air Development Center

The results of limit of flammability, limit of ignitibility, and ignition temperature tests conducted on aircraft fuel vapor-air mixtures by the U.. Bureau of Mines Gaseous Explosions Laboratory between February 19, 1950 and February 19, 1952 are presented. Two aviation gasoline grades 100/130 and 115/145 and two jet fuels grades JP-1 and JP-3 were investigated. A limited amount of work was done on the ignitibility of JP-1 mists and sprays and on the ignition temperatures of aircraft hydraulic fluid AN-0-366.

Nicholas P. Setchkin

Tests of 47 specimens of solid materials as requested by the advisory group to Subcommittee V, ASTM Committee E-5 on Fire Tests of Materials and Constructions were made at the National Bureau of Standards for the purpose of evaluating a technique for determining the combustibility classifications of solid materials. Results of these tests indicate that by using the technique proposed for adoption by ASTM, the specimens, except for a few, could be readily classified as combustible or incombustible. The results for those few were not conclusive ands seem to require further definition of the procedure and method of classification.

J.J. Gassmann

Laboratory tests have been conducted to determine weather aluminum oil tanks located forward of aircraft power plant fire walls are potential fire hazards. Three series of tests were conducted on various types of oil tanks, both coated and uncoated.