PBS Program Focuses On In-Flight Fire Danger

A new program to air on PBS later this month reports the majority of America's civil aviation fleet is prone to undetectable and unfightable in-flight fires. "NOVA Presents: Crash Of Flight 111" further alleges the FAA and the airline industry have been aware of this problem since 1993 and have, in the case of most recommendations from the Canadian Transportation Safety Board, failed to act.

NOVA, renowned for its scientific approach to technically complex stories, takes an inside look at the Canadian investigation into the watery crash of Swiss Air Flight 111. On September 2, 1998, the crew aboard that New York to Geneva flight reported smelling smoke in the cockpit approximately 53 minutes into the flight. The MD-11 was diverted to Halifax, Nova Scotia for a non-emergency landing. Upon reaching the vicinity of the airport, the crew decided the aircraft was too high and too heavy for a safe landing -- especially given the possibility of a fire. So they turned back out to sea to dump fuel and lose altitude.

That's when things started going horribly wrong for Flight 111. The CTSB, in a report last year, wrote, "About 13 minutes after the abnormal odor was first detected, the aircraft's flight data recorder began to record a rapid succession of aircraft systems-related failures. The flight crew declared an emergency and indicated a need to land immediately. About one minute later, radio communications and secondary radar contact with the aircraft were lost, and the flight recorders stopped functioning. About five and one-half minutes later, at 10:31 p.m. Atlantic daylight saving time (ADT), the aircraft crashed into the ocean about five nautical miles southwest of Peggy's Cove, Nova Scotia, Canada. The aircraft was destroyed and there were no survivors."

That was the beginning of a four-and-a-half year long, $39 million investigation into why Flight 111, with all 229 people on board, disintegrated upon impact with the Atlantic Ocean, just sig smiles from Peggy's Cove, Nova Scotia.

Investigators knew there had been a fire on board Flight 111. But they were unable to figure out where or how it started.

NOVA, which is produced by WGBH-TV in Boston (MA), reports the investigation was all but finished without conclusion when a Canadian investigator, wrapping up his inconclusive report on the accident, came across evidence that an electrical arc within the aircraft's in-flight entertainment network (IFEN) may have sparked the fire. Eventually, the CTSB concluded, "Reconstruction of the wreckage indicated that a segment of arced electrical cable associated with the in-flight entertainment network (IFEN) had been located in the area where the fire most likely originated. The Board concluded that the arc on this electrical cable was likely associated with the fire initiation event. The Board also concluded that it is likely that one or more additional wires were involved in the lead arcing event, and that the additional wire or wires could have been either IFEN or aircraft wires. Therefore, it could not be concluded that the known arcing event on the IFEN cable located in the area where the fire most likely originated was by itself the lead event."

NOVA reports the electrical arc, generating up to 12,000 degrees (F), ignited the supposedly fireproof mylar insulation surrounding the interior of the aircraft. The program quotes experts who say, in aircraft where there's as much as 150 miles of wire on board, there can be up to 1500 cracks in wiring insulation. Couple that with the type of condensation typical in the upper compartments of an aircraft in flight and NOVA's experts suggest the possibility for a disastrous in-flight fire event are extraordinary.

Isn't that metalized mylar insulation, variants of which are used in most commercial aircraft, supposed to be fireproof? It is. But it isn't, reports NOVA. The program quotes one NTSB official who acknowledged the flammability of metalized mylar, saying, "I think quite clearly that there was an oversight, that the testing procedures were not adequate to reveal the danger from this metalized mylar. And it took a tragedy such as Swiss Air 111 to highlight that more needed to be done in this area."

Further, the PBS program reports silicone end caps used in air circulation ducts -- also certified by the FAA as fireproof -- burned after just four seconds' exposure to an ignition source. The end caps were flame-tested at the FAA's testing center near Atlantic City (NJ).

"I think it was a surprise to a number of people," said a CTSB official, "and not just our team. It certainly was a surprise to me. I didn't think it would burn like that. I never even thought about it. I think that most of the other pilots in the world would be in the same boat."

With the end caps burned away, fresh air was allowed into the area where the metalized mylar was already burning, lending fresh fuel to the fire and forcing the flames toward the overhead wiring compartments above the cockpit.

NOVA reports the flight crew, which originally believed they had time to dump fuel and descend at a reasonable rate, actually ran out of time. The fire burned through the cockpit ceiling, filling the cockpit with fire, smoke and toxic fumes. Before their power and sensor leads were burned out by the fire, the flight data recorder indicated a loss of primary instrumentation, forcing the flight crew to rely on hard-to-read backup instruments and, finally, trying to fly over water at night, peering through a smoke-filled windscreen.

"The pilots seat was retracted," said Ken Adams, the ALPA representative to the Swiss Air 111 investigation. "So we have a pretty good indication he was not in his seat, which means to me he was actually up fighting the fire. He was probably using a fire extinguisher. But if he didn't have any protection from the toxic gasses, then he was probably disabled."

The Legacy Of Swiss Air 111

The most stinging allegation uncovered in the NOVA story on Swiss Air 111 is that the FAA and airlines knew about the flammability of metalized mylar as far back as 1993, after an MD-11 burned on the taxiway at an airport in Denmark. The program reports an MD-87 also burned on the tarmac in China. In fact, NOVA sources allege there were several aircraft fires in China during the 1990s -- so  many, in fact, that Chinese officials contacted the FAA and suggested "you guys might have a flammability problem." But NOVA reports there was no action taken by the FAA until after the Swiss Air tragedy.

The FAA eventually did order airlines to remove the metalized mylar used by McDonnell-Douglass in its passenger aircraft by this year. The airlines quickly appealed and were given until next year to remove and replace the insulation.

The CTSB issued 23 recommendations on improving the fire detection and protection philosophies among aircraft manufacturers and air carriers. Replacing the metalized mylar was chief among them. But they also included adding detection capabilities in inaccessible parts of aircraft -- the wiring compartments in particular.

"The TSB believes that the risk to the flying public can be reduced by re-examining fire-zone designations in order to identify additional areas of the aircraft that should be equipped with enhanced smoke/fire detection and suppression systems. Therefore, the TSB made the following recommendation:

"Appropriate regulatory authorities, together with the aviation community, review the methodology for establishing designated fire zones within the pressurized portion of the aircraft, with a view to providing improved detection and suppression capability. A00-17 (issued 4 December 2000)

"Along with initiating the other elements of a comprehensive firefighting plan, it is essential that flight crews give attention, without delay, to preparing the aircraft for a possible landing at the nearest suitable airport. Therefore, the TSB made the following recommendation:

"Appropriate regulatory authorities take action to ensure that industry standards reflect a philosophy that when odor/smoke from an unknown source appears in an aircraft, the most appropriate course of action is to prepare to land the aircraft expeditiously. A00-18 (issued 4 December 2000)

"Aircraft accident data indicate that a self-propagating fire can develop quickly. Therefore, odor/smoke checklists must be designed to ensure that the appropriate troubleshooting procedures are completed quickly and effectively. The TSB is concerned that this is not the case, and made the following recommendation:

"Appropriate regulatory authorities ensure that emergency checklist procedures for the condition of odor/smoke of unknown origin be designed so as to be completed in a time frame that will minimize the possibility of an in-flight fire being ignited or sustained. A00-19 (issued 4 December 2000)"

Advice Ignored?

The problem, according to NOVA, is that these safety recommendations are not being implemented by the FAA, considered the world's leader in implementing aviation safety protocols.

"We're presently having new airplanes designed -- they're on the drawing board," said ALPA's Ken Adams. "Boeing has one. Airbus has what's called the Airbus 380, a 550 passenger airplane. The regulations haven't changed. They don't have to provide any more fire detection or fire protection than we had on Swiss Air 111."

"NOVA Presents: Crash Of Flight 111" airs on PBS stations February 17th at 8:00 p.m. EST.

FMI: Canadian TSB Report On Flight 111, www.pbs.org/nova/aircrash