O.W. Preston, Dr. G.W. Kibbee, R.H. Muroyman, R.A. Storley

Studies and tests were conducted to develop a basic methodology for predicting the test aircraft stopping distance on a wet runway. Development consisted of a series of wet and dry runway tests utilizing the FAA Variable Slip Runway Friction Tester and an instrumented non-flyable test aircraft followed by an analysis of the test results using an analog computer simulation of the aircraft. A relationship was established between wet runway friction measured by the friction tester and friction available to the braking wheels of the test aircraft. The methodology consists of using this relationship and an analog computer aircraft simulation, incorporating actual anti-skid and braking system hardware, to prepare a nomograph showing aircraft stopping distance as a function of the runway friction measured by the FAA Variable Slip Runway Friction Tester. Correlation exists between friction measured by the friction tester and friction available to the tires of the test aircraft when normalized with respect to theoretical hydroplaning velocities. The relationship is that. M.AXA/ C equals O. 59 times I" MAX when the ratio between aircraft and friction tester velocities was equal to the ratio between the respective theoretical hydroplaning velocities.

Thomas Rust, Jr.

The work performed under this project was directed toward establishment of standard Test conditions for testing materials which are intended for use as fire barriers for protection against a jet engine combustion chamber burn-through type of failure. The development of such a failure was accomplished on a General Electric J-47 jet engine. The resulting flame was quite severe, penetrating the present standard firewall material in 2 seconds. Studies were made of the flame impingement characteristics, including impingement temperatures and pressures; and various potential firewall materials were tested for effectiveness as fire barriers for protection against such a failure. Most materials tested in this manner failed to provide adequate protection against such an engine failure.

An investigation was conducted toward development of a means of simulating a combustion chamber burn-through failure with the ultimate goal of developing a suitable laboratory test flame for evaluating potential firewall materials. A combustion chamber simulator, which will produce a flame of similar severity to the flame produced in the J-47 engine, was developed. However, more effort is required to further develop this simulator so that exact simulation is possible.

Constantine P. Sarkos

A 28-foot titanium fuselage was exposed to a 400-square-foot JP-4 fire for about 2 ½ minutes. The titanium fuselage remained intact, thus preventing any flames from entering into the cabin. Heating of the cabin pressure sealant and insulation caused these materials to burn. This, in turn, caused significant increases in temperature, smoke, and toxic combustible gases within the cabin at about 1 minute after fuel ignition and a flash fire at 2 minutes. Theoretical heat transfer calculations were compared with thermocouple data from a section of the fuselage where the insulation did not burn. This comparison indicated that if the insulation and sealant were “inert” habitable conditions would have been maintained within the cabin for at least 5 minutes, and perhaps more.

E.B. Nicholas

To determine the flammability characteristics of several interior materials removed from the cockpit and cabin areas of a Federal Aviation Administration, DC3 aircraft that crashed and experienced fire damage.

American Society for Testing and Materials

This method covers a laboratory determination of the self-ignition and flash-ignition temperatures of plastics using a hot-air ignition furnace.