Wednesday, August 29, 2001



 Toughen standards - TSB 

Swissair crash was preventable, investigators say



By RICHARD DOOLEY -- The Daily News

Swissair Flight 111 crash investigators say tough fire safety standards are needed to protect air passengers from the type of fire that sent the doomed jet plunging into the sea near Peggy's Cove three years ago. Less than a week before the third anniversary of the Sept. 2, 1998 crash that killed all 229 aboard the New York to Geneva MD-11, the Transportation Safety Board called yesterday for better flammability standards for all
materials used in the manufacture of aircraft, especially wiring.

In three broad-reaching recommendations announced at an Ottawa news conference, chief investigator Vic Gerden said a fire such as the one that disabled Flight 111 should not cause a catastrophe.

"It is time to raise the bar on the type of material that is put in airplanes," said Gerden.

Stringent flammability regulations are applied to materials in the passenger compartments of aircraft, but Gerden said there are fewer restrictions on materials used in inaccessible areas of planes.

The board is particularly concerned about the testing of aviation wiring that examines only individual wires, not live wire bundles, and doesn't look at how wires can ignite a fire.

TSB investigators speculate a short-circuit aboard Flight 111 may have ignited a fire fed by flammable material above the cockpit ceiling.

Frighteningly, one of the devices intended to help the pilots get the plane to safety may have contributed to the fire.

The MD-11's emergency oxygen supply, intended to feed fresh air to the cockpit crew during a fire, may have instead fed the fire.

Investigators found the stainless-steel oxygen lines had aluminum fittings, which could leak during a fire and feed enough oxygen to turn a small blaze into an inferno.

The TSB hasn't determined the cause yet, and expects to release a final report in a year.

Lyn Romano, who lost her husband Ray aboard Flight 111, said she is pleased by the recommendations.

"But the fact these issues have been out there for 20 years or more without being addressed should be appalling to everyone," she said in a telephone interview from her New York home.

Romano founded the International Aviation Safety Association after the crash to press the U.S. Federal Aviation Administration - the world's leading aviation regulator - for better standards.

FAA spokesman Les Dorr said that while the TSB's recommendations are noted, the organization is not likely to act on them.

"We take it seriously, but we have to ask whether or not it is practical to implement," said Dorr.

The FAA's own wire standards are under review, but no problems have yet been found, said Dorr. He said the FAA must have data from the U.S. civil aviation fleet before new rules are made.
http://www.hfxnews.southam.ca/story6.html

  Link to IASA response to The FAA's Les Dorr

IASA Commentary:  Re the TSB's "aluminium endcaps on the oxygen lines".

If arcing aromatic polyimide (Kapton) wiring bundles are in contact with or in close proximity to the flight-deck's stainless steel oxygen lines, you have essentially the equivalent of an arc-welder at work. Temperatures far in excess of the melting point of most (if not all) alloys of stainless steel are easily achievable. Once the Stainless Steel high-pressure oxygen line is broached, you then have a pin-point source of incendiarising oxygen - a "blow-torch effect" that will obviously incinerate anything - and one that will certainly propagate the fire widely (and wildly). It may well explain the fan-shaped burn patterns found behind the cabin linings in the ceiling crown by the TSB (which then led them to carry out airflow tests airborne). An oxygen blowtorch obviously doesn't need flammable and combustible materials in order to wreak havoc with other wiring, systems and structure.

 And also of course, if the crew is totally dependent upon that oxygen for their consciousness, well..... that's all she wrote. If the final emergency upgrade by the sr111 pilots was in fact precipitated by just such an outbreak, no-one should be surprised.

So the TSB's isolated "aluminum endcaps" are neither the beginning nor the end of the story when you consider what can be done to systems and other flammables by an arcing wire-bundle. Not so long ago an arcing wire-bundle burnt through an MD-83's fuselage skin. Part of the solution is obviously to quench such a fire very effectively by promptly getting the electrical power off the wiring. Current "smoke of unknown origin" checklists just do not do that. They attempt to trouble-shoot the source of smoke and fumes and these delays can lead directly to the sr111 scenario. This is something that the TSB is still tip-toeing around. The MD-11 Chief Test Pilot at Long Beach (Tom Melody) released a pilot's bulletin almost two years ago which admitted that running the smoke and fumes checklist would take in excess of a lethal 35 minutes. You can view that under Tell-Tale Docs on the IASA web-site. Melody added that, because of the MD-11 design (meaning the smoke/elec/air switch), there appeared to be no alternative approach by which they could expedite matters. That's the reason why three years later crews smelling fumes have no other guidelines than "Land ASAP". That so-called solution can become a panic-stricken process that is itself accident-prone - whether or not there is a fire. There are other methodologies for coping with airborne electrical fire and smoke, ones that ALPA is aware of and are looking into. You can read about them on the IASA web-site or email us and we will provide you with the data.

I agree with Vic Gerden that it doesn't really matter where or how the fire started. It could have been the InFlight Entertainment System (IFEN), map-lights, ceiling fleuro-lights, entry-doors chafing on ceiling wires or the bus-tie sensing relay that was swapped out and shorted during maintenance a few flights before. The problem is that, as the TSB has said, it looks like it was an electrical fire and no one failure should be able to bring a plane down. If the airlines insist upon living with Kapton wiring, then they have to find a checklist that quickly gets the power off that lethal type of wiring. In order to be able to do that, they need a Virgin Bus. The Virgin Bus is quite simply a standalone integral electrical system that powers all the "get you home in bad weather at night" type essential flight-deck systems. You may not have inflight entertainment, a hot meal or a reading light - but at least you will be sure of getting where you're going - simply because the electrical system that had the problem has been inerted and because the Virgin bus is designedly a very high integrity system that has nil commonality with the standard aircraft electrical system. It is solely a normally unpowered electrical fall-back position. Because of the tentacular miles of wiring in a modern airliner and the possibility of a continuously powered hidden fault quickly turning into a blazing inferno, the sensible solution MUST BE that the power should quickly come off the wire. Arc Fault Interrupt Circuit Breakers (AFCI) may eventually improve that situation - but as yet they are an unproven technology. So if crews had this solution at their fingertips the high accident potential of LANDING ASAP anywhere they can, (despite the nasty weather and with a heavy aircraft) would also fade away. If weather dictated, crews could press on to their original destination if they wished.

These are some of the points that the TSB did NOT make, and perhaps could not - within their responsibilities. However they are certainly the points that should now be debated sensibly. I have a feeling however that the FAA will simply apply their cost/benefit formula and say that it's all statistically not doable. In fact Les Dorr has already said as much.

So the airline passenger public, whilst sitting through their next airborne emergency, should reflect upon whether they consider the FAA's approach to aviation safety is actually "raising the bar" or simply "barring the way".
Wednesday, August 29, 2001 Back The Halifax Herald Limited
Tougher standards urged in Swissair crash report

Analysts cheer recommendation to beef up tests on plane wiring

 

Tom Hanson / The Canadian Press
Vic Gerden, lead investigator in the Swissair crash investigation, reads his statement while Benoit Bouchard, chairman of the Transportation Safety Board of Canada, listens at a news conference in Ottawa on Tuesday.

By Brian Underhill / Ottawa Bureau

Ottawa - Regulators should require more stringent testing of electrical wiring used in aircraft, investigators of the crash of Swissair Flight 111 said Tuesday.

That was one of three recommendations contained in a report released Tuesday by the Transportation Safety Board.

Board officials also want tougher flammability standards for materials used in pressurized areas of aircraft and an evaluation of air conditioning and cockpit oxygen systems to determine if they can aggravate a fire already in progress.

The recommendations are aimed at reducing the risk of inflight fires like the one that caused the deadly plane crash, which occurred Sept. 2, 1998, off Peggys Cove.

"Our purpose in issuing these recommendations now is to enhance the safety of the travelling public as quickly as possible," board chairman Benoit Bouchard said Tuesday.

"Today, we wish to draw attention to a number of safety deficiencies related to flammability, the tendency of certain materials used in the construction of aircraft to cause or sustain an inflight fire," said Mr. Bouchard, who also announced he's resigning from his post after five years.

Tuesday's report, particularly the recommendation dealing with testing of wiring, was welcome news to one of the aviation industry's most vocal critics.

"That's a giant leap for humankind," said Ed Block, a Philadelphia wiring expert with the International Aviation Safety Association.

"That's the igniter. That's the genesis of all the problems you're going to encounter in the air."

Investigators expect to complete their investigation of the crash, which killed all 229 people aboard, next year.

Pilots reported smoke in the cockpit about 53 minutes after Flight 111 left New York en route to Geneva. The plane's electrical systems began failing about 15 minutes later, and the jet plunged into the Atlantic Ocean six minutes after that.

Cycling pilgrimage

Over two million pieces of the plane have been brought up from the ocean floor during the investigation, which has cost $52 million so far.

Investigators have found extensive fire damage above the ceiling in the front section of the aircraft. While the origin of the fire has not been determined, Mr. Bouchard said investigators know that the fire could have been ignited by an electrical arc from a wire.

"But a fire has many parts," he said. "It needs an ignition source. It needs material to burn. It needs a flow of fresh air to feed it. Each of these elements needs to be addressed, and today's recommendations speak to several of them."

Vic Gerden, the board's lead investigator in the Swissair case, said tests are being carried out on 20 burnt wires - measuring anywhere from a few centimetres to about a metre - that were damaged by electrical arcs between wires on the doomed MD-11.

But he said it is extremely difficult to determine if the arcing occurred before or during the fire.

He expects to get those test results in the next week or so, but noted they may not provide conclusive answers.

Mr. Gerden, who said that over 6,500 pieces of the plane were fire-damaged, also said there is still some material to be tested in an effort to determine how the fire developed and how fast it spread.

"The analysis of how these materials, either alone or in concert, have contributed to the progress of the fire . . . is pretty complex, and it is ongoing," he told reporters Tuesday.

Mr. Gerden said the objective of the probe is not simply to find the origin of the fire because that is "just one link in that chain of events that led to the crash."

"An airplane should not crash as a result of one ignition source."

Mr. Block has been fighting for safer aircraft wiring for years. He co-authored a report, released earlier this month, that looked at aviation incidents around the world over the last three decades.

Mr. Block praised the safety board for recommending tougher tests that he says are long overdue. But real change will depend on whether regulatory agencies such as the powerful Federal Aviation Administration in the United States turn the recommendations into new rules.

"This is an issue that is being addressed with research that the FAA started, and more will be done over the next few years," FAA spokesman Les Dorr said.

Transport Minister David Collenette also noted that recommendations like those made Tuesday will require international co-operation among regulators, manufacturers and the airline industry.

"The (board's) recommendations involve very complex issues that cannot be resolved overnight," he said Tuesday.

His department has taken a lead in encouraging authorities like the FAA and European Joint Aviation Authority to develop a plan to address issues like material flammability and wiring properties, he said.

Tuesday was the third time the board has made safety recommendations in the course of the investigation, with previous reports focusing on issues ranging from aircraft wiring to flight recorders, thermal acoustic insulation, map-lights, inflight fire-fighting equipment and emergency procedures.

Previous recommendations include:

- Cockpit wiring on all MD-11s should be inspected.

- Flight recorders should have independent power sources and the capacity to record up to two hours rather than 30 minutes.

- Use of metallized Mylar blanket insulation, found to be flammable, should be reduced or eliminated.

- The airline industry should fully review fire-fighting capabilities and improve fire suppression and detection equipment on planes.

http://www.herald.ns.ca/cgi-bin/home/loadmain?2001/08/29+211.raw 

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