Bureau of Air Safety

During 1988 the aviation service and regulatory divisions of the Department of Transport & Communication (DTC) will be amalgamated to become the Civil Aviation Authority.

A.J. Allerton

The purpose of the tests was to establish compliance of the European OSU equipment operators with regulation FAR 25.853 Appendix F, Part IV Amendment 25-61, and give a comparison of the test results from European OSU equipment with the results obtained from identical specimens tested by the FAA Technical Centre, Atlantic City, USA.

Richard D. Bloomberg, Edward W. Bishop, John W. Hamilton

This technology assessment determined the feasibility of FAA support for development of a computer-based system to supplement cre'w function during in-flight fire/smoke incidents. The system was designated Aircraft Command in Emergency Situations (ACES). It was limited to fire/smoke incidents in areas other than power-plant or lifting and control surfaces. It would be used in large commercial air transports. Thirteen scenarios of in-flight fire/smoke incidents which had occurred or were likel y to occur were written to define the events to which a flight crew might have to respond. The responses to each scenario, based on current practice, were described and presented on a timeline. The development of each incident was described as were the significant operational and environmental features. An analysis of each scenario was then made to identify problems encountered in detection and management of the incident. Separate analyses of current sensor technology, aircraft computer/display technology,' and of human factors led to a hypothetical ACES system using smoke/heat sensing with determination of rate and extent of change in both. ':'he postulated ACES was incorporated into the master warning concept with advisory displays forced to the cockpit. The scenarios were reanalyzed using the ACES and results compared to the first scenario analysis. It was concluded that, an ACES is technological I y feasible and can be used in and facilitate air creW: emergency procedures. Training will be needed but crew workload will not be negati vel y affected. In almost every incident the ACES concept significant! y reduced reaction tice and severity. The continuation of ACES development is encouraged.

Timothy Marker

Tests were conducted on the cargo liner burnthrough apparatus simulating the design features of actual cargo liners. The design features include joints, seams, fastening systems, corners and a light fixture. Due to geometric constraints, many of these design features cannot be readily tested in the prescribed cargo liner test rig, and therefore a standardized method of testing has been developed.

Patricia L. Cahill, James H. Dailey

Electrical wet-wire are tracking is a phenomenon that has been known for many years. This can occur when leakage currents on a wet insulation surface are great enough to vaporize the moisture, resulting in the formation of dry spots. These dry spots offer a high amount of resistance to current flow. In turn, an induced voltage will develop across these spots and result in the occurrence of small surface discharges. Initially, these discharges will appear as scintillations at the insulation surface. These discharges produce highly localized temperatures on the order of 1000 degrees Centigrade ©. Temperatures of this magnitude will cause thermal degradation of the insulation material, the nature of which depends on the insulation material used.

The Federal Aviation Administration (FAA) conducted a series of bench scale tests which demonstrated that the ability of an aircraft wire to resist wet are tracking and possible flashover is highly dependent on the composition of the wire insulation. In addition, the conductivity level of the electrolyte may influence the time and the type (arc track or open circuit) that can occur.