William J. Crawford, III

Based upon initial testing, it was concluded that T64 engine could operate on emulsified fuel (JD1) without any engine or control adjustment or modifications. This was accomplished without loss of performance or deterioration of engine components.

A. Beerbower

The current incentive for safety is due to excessive loss of aircraft in Vietnam due to fires. Evaluation of four classes of thickened fuel eliminates "canned-heat" gels, the visco-elastic Napalm type, and the polymer-thickened fluids.

J.R. Gibson, D.B. Nelson, R.A. Anduze, J.C. Harris

The objective of this project was to investigate a low density interconnected, 10 pore to the inch, cellular polyurethane ester foam under extremes of environmental conditions for use as packing material for fuel system applications. A variety of simulated aircraft and environmental tests were conducted which established that the foam and the various hydrocarbon fuels are compatible. Investigated were JP-4, JP-5, Avgas, type I and III test fluids. JP-4 fuel retention at ambient conditions was measured at 0.95 volume percent, and 1.2 volume percent for Avgas.

Static exposure of the foam and fluids for 28 days at 158° F (110° F for Avgas) and at 65° F causes no significant changes in compression load deflection, tensile strength, or elongation. A simulated field exposure consisting of a cyclic temperature environment (70° to 130°F) and high humidity did not adversely affect the foam. Tumbling tests on foam in fuel at 65°F resulted in slight weight loss due to fragmentation; however, similar testing in the absence of fuel to cushion the foam resulted in appreciable foam fragmentation. Washing action of the fluids removed particulate matter form the matrix of the foam. This washing also extracted a very low percentage of an alkyl phthalate ester from the foam which had a tendency to increase the gum content of the fuel.

The foam material appeared to have no corrosive effects on two aluminum alloys: MIL-C-6529 corrosion preventive oil remained effective and had no detrimental effect on the foam

The various parameters affecting vent icing in a foam filled tank were studied. Each parameter, including void area, foam temperatures, was systematically varied throughout realistic extremes and vent icing conditions measured. Conditions favoring icing were developed as well as tank vent voiding criteria for the foam

The temperature-pressure relationship across the pressure chamber of the foam filled dynamic flow tester was not significantly affected over the range of fuel velocities and temperatures tested for either JP-4 or Avgas.

Coleman P. Donaldson, K. Evan Gray

An extension and improvement of Warren’s momentum integral method for predicting the turbulent mixing and decay of axially symmetric, compressible, free jets o the case of the mixing of dissimilar gases is discussed. Two ideal gases having different molecular weights and specific heats are treated with the assumption that the local turbulent mixing rate at each axial location depends upon a suitably chosen local reference Mach number. This method of analysis is then compared with the results of a series of jet-mixing experiments carried out o helium, methane, nitrogen, carbon dioxide and freon jets mixing in air. Mach numbers ranging from 0.75 to 3.30 were investigated. The character and mixing rates of both properly and improperly expanded supersonic jets were studies. It is concluded from a comparison of these data with the theoretical method presented that a general relationship exists, at each axial position I the jet, between a local mixing rate parameter and the local Mach number. This general relationship is independent, within the accuracy of these experiments, of the physical properties or the thermodynamic state of the mixing gases.

Jim Brenneman

The Cleveland tests were conducted to determine if survival time in an aircraft cabin could be extended under post-crash fire conditions by using high expansion foam to completely fill the occupied portions of the cabin interior. It was hoped that the high expansion foam would hold the temperature within survivable limits while controlling smoke, toxic gases, and other products of combustion. Thus, we would provide cool, breathable atmosphere for a prolonged period of time for the occupants, pending ultimate evacuation or rescue.

As a secondary objective, we hoped to determine the exact nature of the smoke, gases, etc., that may be present in a post-crash fire in which typical modern aircraft cabin materials such as vinyl, polypropylene, polyvinyl chloride, etc, and plastics are installed and are involved in the fire.

To these ends, the tests were only to prove the concept, since the foam equipment used was “off the shelf” hardware, and not suitable for use as an installed system. It would also not be suitable for use in its present form by ground fire fighting, since it is too slow and cumbersome to put into operation.