Similar Safety Issues Spur Differing Responses In Commercial And Military Aviation Sectors

Air Safety Week,  Feb 4, 2002  

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The commercial airline industry both leads and lags the military in various safety programs, and the two sectors could profit through better sharing of information, according to a recent investigation of safety oversight practices.

The investigation was conducted by the U.S. General Accounting Office (GAO), the investigative arm of the U.S. Congress. The January 2002 report (No. GAO-02-77) concluded that although the Federal Aviation Administration (FAA) and the U.S. armed forces operate comparable aircraft types (helicopters, transports such as B737, B747, DC-10, etc.), "Similar aviation safety concerns do not necessarily lead FAA and the military services to take the same actions to mitigate or eliminate them, or to act at the same pace."

In some cases the FAA, often criticized for the glacial pace of its safety-related regulatory activity, is years, if not decades ahead of the military. In other cases, the FAA has not been nearly as proactive and is distinctly years behind military practices and programs.

The GAO review presented six case studies. Details are highlighted below:

Aromatic polyimide insulation. Sometimes referred to by its trade name, Kapton, the military services have restricted its use, as in the U.S. Air Force, removed it from moisture-prone areas, as in the case of the U.S. Navy, or undertaken costly programs to remove it entirely from aircraft, as did the U.S. Coast Guard in the case of its H-65 helicopters. The U.S. Army is removing this wire type gradually from its aircraft to counter a chafing problem. According to the GAO report, "As of June 2001, aromatic polyimide had been removed from 1,389 of the 1,523 Blackhawk helicopters in the Army's fleet."

Even though aromatic polyimide dominated findings of the Aging Transport Systems Rulemaking Advisory Committee (ATSRAC), the FAA has not mandated its removal, consigning the problem to further study and wiring-related research (see ASW, March 19, 2001).

An FAA official told GAO investigators that rules permitting the use of aromatic polyimide 20 years ago "would prohibit it today because of the failure modes that have been identified." This statement was made with particular regard to the explosive properties of aromatic polyimide wiring under arcing conditions. As reported in this publication, the FAA is placing its primary hope in arc fault circuit interrupter (AFCI) technology to reduce the hazard posed by in-flight arcing. However, the AFCI technology is years from deployment and basically deals with a wire failure more promptly after it has occurred (to include pernicious "ticking faults") rather than before the integrity of the insulation has been compromised by age, wear and exposure.

Mid-air collision avoidance technology. Also known as Traffic Alert and Collision Avoidance Systems (TCAS), the FAA has been pushing deployment of this lifesaving technology for at least the past 13 years. It is now pushing for deployment of the more advanced TCAS II on all regional aircraft with 10 or more seats, and most recently for cargo aircraft (see ASW, Nov. 19, 2001). According to the GAO, the military has lagged. As examples, the Army won't have its fixed- wing aircraft TCAS-equipped until 2006, and the Air Force did not start installing TCAS in its passenger-carrying aircraft until 1996, some three years after TCAS had been installed in all large jetliners.

Terrain avoidance warning systems (TAWS). A similar tale applies with this technology - the military has lagged far behind the commercial sector. The FAA has pushed for the deployment of ground proximity warning systems (GPWS) since 1974. The enhanced version of this technology (EGPWS) with its vital "look ahead" function has been required on large jets since March 2000. The fatal 1996 crash of an Air Force jet, a military variant of the B737, carrying then Commerce Secretary Ron Brown, galvanized the Air Force into deploying EGPWS technology. The accident aircraft had been outfitted with GPWS but not the enhanced version. As one commentator observed, the accident that killed Secretary Brown likely would not have happened if the aircraft had been equipped to civilian standards.

Flight operations quality assurance (FOQA) programs. The FAA and the airline industry are well ahead of the U.S. military. "Efforts by the military services to initiate FOQA programs are in the very early stages, with the Air Force taking the lead through a demonstration project using C-17 aircraft," the GAO observed. The situation by service is revealing:

* Air Force: Has a one-year demonstration FOQA project; will use a maximum of 30 C-17 jet transport aircraft.

* Navy: Still debating whether FOQA should be used as a training tool to improve aviation safety or as an enforcement tool to protect taxpayer investments in naval aircraft. According to a senior Navy Safety Center official, implementing FOQA in the Navy would be a "tough sell" given competing needs, such as funding to repair engines.