Vertol Aircraft Corporation

Testing was conducted to demonstrate the ability of the H-21 self-sealing oil tank and components to retain oil if there a fire in the engine compartment

Alan Schriesheim

A method is described to burn a given quantity of a combustible material in a fixed amount of air at a selected initial temperature. Analyses of most of the gaseous combustion products were made quickly and comprehensively by means of a mass spectrometer. Hydrogen chloride was not detected with the mass spectrometer because of its adsorption upon the walls of the glass combustion chamber. The concentration of this gas was determined by titrating a water wash of the combustion chamber with a standard silver nitrate solution. Carbon monoxide when present in concentrations below 1,000 parts per million was determined by an indicator method, and when present in concentrations above 1,000 parts per million was determined by the mass spectrometer. Several organic coatings of different chemical composition were burned in a combustion space initially maintained at three temperatures. The lowest temperature (250° C) produced the smallest variety of combustion gases, whereas the highest temperature (550° C) produced the largest variety.

D. Miller

The tests reported herein were conducted for the purpose of evaluating the fire resistance of Aero quip 666000-4, -6, -8 and –16 Teflon hose assemblies, when protected with 624-type single layer fire sleeve.

A minimum standard of flame-resistance is required for furnishing materials used in civil aircraft, as specified in BRITISH civil Airworthiness Requirements, Section D, Chapter D4-3. The materials concerned include, for instance, interior paneling, curtains, carpets and other floor covering, upholstery, interlining and lagging intended for use in passenger, crew or baggage compartments.

Such materials, either inherently or by virtue of their mode of application or size, shall not be a nature that accidental contact with, say lighted matches, cigarettes, or local heating due to electric short circuits or lightning strikes, would lead to propagation of fire which could prejudice safe operation of the aircraft.

The routine assessments of flame resistance suitability are based on the results of tests covering the foregoing conditions and for the purpose of making these assessments the following test methods and criteria or their equivalents are acceptable to the Board.

Charles A. Hughes

Tests were conducted to study the effect of element-wall thickness on the operation of continuous fire-detector systems. Walker Kidde & Company, Inc., furnished the elements tested, and by Thomas A. Edison, Inc. They included the standard, thin-wall, and the heavy-wall types from both companies, and a double-wall Edison element with the same diameter as the thin-wall element. This double-wall element was claimed to be more rugged than the thin-wall element.

The elements first were placed in an electric furnace and subjected o a slow rate of temperature increase to check the similarity of the temperature resistance characteristics of the core materials between the heavy and thin wall elements, because differences would influence the test results. The elements then were tested by placing them over a standard burner at 1500 degrees and 2000 degrees F, to obtain response and clearing times.

A second series of tests was conducted on an installation of the heavy and thin walled elements placed side by side in an engine bay of a test cell mounted F-89 airplane, using controlled test fires during simulated operation of the airplane. The results of the tests indicated that response and clearing times were increased appreciably by use of the heavy wall elements and that these elements did not meet the requirements of SAE Specifications AS-401A, Section 7.1 (Response Time). For the Edison Double-wall element, response and clearing times at 1500 degrees F flame temperature were not appreciably different from those of the thin-wall elements. At 2000 degrees F, however, the response and clearing times of the double-wall element were somewhat longer than for the thin-wall elements. The double-wall element met the specification requirements for response times only when calibrated for ambient temperatures below 450 degrees F.