P.G. Rasmussen

This study investigates the ability of people with normal distant visual acuity to identify self-illuminated emergency signs in a smoke-obscured environment. The results indicate that signs whose background luminance meet or exceeds the requirements of Federal Aviation Regulation (FAR) 25.812 are readable under favorable conditions when the total optical density of the smoke between the observer and the signs ranges between 3.00 and 3.55. Substantial increases in character sizes in the signs produce only moderate improvements in readability.

Some limitations on the practical application of these data to predicting sign visibility in adverse conditions are discussed.

P. Boris & R.Young

A four-phase test program was conducted using Halons 1011 (CB), 1211, 1301, and Halon Foam to determine which of the latter three would be a suitable replacement for 1011. The four phases consisted of determining agent concentration in fixed volumes under quiescent and ventilated conditions; agent decomposition products analysis under these same conditions, but with a four pound cotton fire load; agent throw range; and agent effective range against class A and B fires. Within the constraints of this program, 1211 was the most effective agent during effective range testing and 1011 the least effective.

P.T. Harsha

Because of the high-strength for light weight capability of fiber/epoxy structural materials, a significant increase in their use in commercial aircraft structures has been stimulated by the positive effect on fuel conservation that such structures would involve. However, massive utilization of new materials must be preceded by a thorough examination of any potential hazard created by their use. In the case of carbon fiber materials, a potential hazard connected with the release of the fibers into the atmosphere in an aircraft accident resulting in fire has been identified, and is being evaluated.

Louis J. Brown, Jr.

Fourteen fire tests were conducted with surplus, fire-hardened DC7 fuselage positioned adjacent to a 20-foot square JP-4 fuel fire. The fuselage had a door opening at the center of the fire and door openings displaced from the fire on each side of the fuselage. Temperatures, light transmittances, and heat fluxes were measured for each of these 90-second tests. The opening of doors away from the fire was varied from test to test s was he ambient wind velocity. Wind direction coupled with the door opening configuration were found to be controlling factors in the accumulation of heat and smoke within the aircraft cabin. Heat fluxes into the cabin through the fire door also changed significantly with wind and door openings and depended on the degree of flame penetration through the fire door. When flames did not penetrate into the cabin, the symmetry plane heat flux at the fire door station agreed very well with earlier modeling predictions

George B. Geyer, Lawrence M. Neri, Charles H. Urban

Information was obtained by conducting laboratory experiments and large-scale fire tests which were of value in estimating the fire extinguishing effectiveness of eight Aqueous-Film-Forming-Foams (AFFF), 11 fluoroprotein foams (FPF), and three protein foam (PF) agents.

Large-scale fire tests were performed under fixed fire conditions employing airaspirating and non-air-aspirating nozzles on 82.4-, 101-, and 143-foot diameter Jet A fuel fires. Experiments were performed with only one foam agent which was: considered representative of each class.

Experiments tend to validate the continuation of allowing a 30-percent reduction in the water requirement at certificated u.s. airports when AFFF is substituted for protein foam (Federal Aviation Regulation (FAR) Part 139.49) and to maintain a 1:1 equivalency ratio when fluoroprotein foam is substituted for protein foam. The data also tend to substantiate the validity of allowing an equivalent reduction in water requirements at airports when the 3-percent AFFF, FPF, and PF agents are substituted for the 6-percent agents within each class.