Crash of Flight 111
Web site launch date: February 3, 2004
Program broadcast date: February 17, 2004
On September 2, 1998, Swissair Flight 111 plummeted into the sea off Nova Scotia while en route from New York to Geneva. All 229 people on board were killed. In May 2003, Canada's Transportation Safety Board published its final conclusions from an investigation that took more than four years and cost $30 million. NOVA's cameras were there from the beginning, revealing the inside story of one of the most baffling and intricate aviation investigations ever mounted. On the companion Web site, hear one air-safety expert's views on what's effective and what's not in crash investigations and their aftermath. Also, learn of policy and design changes that have followed crash investigations, see beneath the skin of a typical passenger jetliner to the myriad systems that make it run, and more.
A Wireless Black Box?
Black-box data from several recent major crashes, including SwissAir 111 and all four 9/11 planes, was either lost or irretrievable. This has left some aviation experts thinking the time has come to develop technology to transmit such data to ground stations in real time.
On Crash Investigations
David Evans, the editor of Air Safety Week, discusses the Swissair 111 investigation with an air-safety expert's deep knowledge and a seasoned journalist's objectivity.
Making Air Travel Safer
Learn what steps were taken following major commercial aviation disasters to correct the design of airplanes or the policies that govern their operation.
Anatomy of a Jetliner
In this interactive, get to know a passenger jet from the inside out, from its miles of electrical wires, to its complex ventilation ducts and awesome fuel supplies.
January 29, 2004 03:27 PM US Eastern Timezone
Exclusive Investigation: NOVA/PBS Investigate the Swissair Crash of Flight 111 and the Safety Recommendations That Have Yet to Be Implemented by the FAA
for Tuesday (Feb. 17)
--(BUSINESS WIRE)--Editor's Note - A copy of this program and expert interviews are available by contacting Jonathan Renes at 617-300-4427, firstname.lastname@example.org. Press Release and photography are available at http://pressroom.wgbh.org/nova
WHO: NOVA, PBS' award-winning science series that airs nationally
Tuesdays at 8pm ET.
WHAT: NOVA's cameras exclusively document the findings from the
investigation of the accident involving Swissair Flight 111.
Swissair Flight 111 took off from New York City bound for
Geneva, Switzerland with 229 people aboard on September 2,
1998. The flight crashed into the Atlantic Ocean off the coast
of Nova Scotia, leaving no survivors.
WHEN: Crash of Flight 111 airs on NOVA Tuesday, February 17, at
8PM ET/PT on PBS (check local listings).
NOVA was given unprecedented access to one of the most intricate aviation investigations ever mounted. This investigation cost $40 million, took four years, and involved a search for evidence among two million pieces of debris. Investigators eventually confirmed that the cause of the accident was a fire set off by conditions that still exist on many planes today.
In March of 2003, the Canadian Transportation Safety Board made twenty-three recommendations to the FAA to improve flight safety, including the installation of smoke detectors and video cameras to reveal hidden fires, providing black boxes with a back-up power supply, increasing the size and visibility of standby instruments, stricter standards on aircraft wiring, new flammability standards and the removal, from all airplanes, of the insulation material that burned in the Flight 111 accident, Metalized Mylar. To this date the FAA has not approved most of the recommendations that were made - including the installation of additional fire detection and suppression devices.
"If the cabin of a modern jetliner was a restaurant or a nursing home, it would fail safety standards and would not get an occupancy permit," says David Evans, editor-in-chief, Air Safety Week.
In the end the culprit for the fire on Flight 111 was faulty wiring located in the attic of the plane above the cockpit. A spark ignited materials - previously thought to be nonflammable - spreading smoke and fire in to the cockpit, blinding the pilots. Had there been fire detection and suppression devices in the airplanes attic, the disaster could have been avoided.
Let's just hope this is not still another 'kapton wiring' documentary. The spark was found on the ENTERTAINMENT SYSTEM WIRING- let's hope Nova mentioned that. There are those that would blame every crash on kapton wiring- rest assured swissair wasn't one of them. The Kapton agenda was around prior to sr111. I think the Canadian final report is pretty clear on this point. Let's not let the bad guys off the hook. Mark and I sent them plenty of compelling information and I hope it wasn't ignored. I just want the truth told about what happened to my daughter.
I think I have to go away with my daughter when this Nova documentary is aired. If any one is able to give a synopsis on it I would really appreciate that. Thanks.
The FAA is dragging its feet on safety recommendations resulting from the crash of Swissair Flight 111 according to the producers of a documentary television special on the crash. The Canadian Transportation Safety Board issued 23 recommendations from its investigation of the crash, which occurred off the coast of Nova Scotia while the flight was en route from New York to Switzerland. The documentary, to air Feb. 17 on NOVA, says few of the recommendations have been adopted...
This documentary appears to be a repeat of several others that were done before the final report came out last year. Instead of mentioning that the investigators actually found the arcing on an entertainment system wire, it is referred to as cable- leaving the viewer confused as to where the fire originated. An accurate book needs to be written about this tragedy before the real story fades into oblivion. I have no problem with the points they bring up but as far as I can see it leaves a huge part of this story out.
NOVA: The Deadly Legacy Of Swiss Air 111
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 221 people on board, disintegrated upon impact with the Atlantic Ocean, just six 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.
WGBH-TV in Boston (MA), which produces NOVA, 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)"
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.wgbh.org
The aero-news.net article that CD posted (thanks, CD) states:
quote:The language here is tricky. The TSB's term "lead event" apparently refers to the actual source of ignition. However ... The existance of the arced IFEN wire implies that there must have been a second wire invoved, since there has to be an electrical potential to create an arc. And the insulation on both wires had to be breached. So whether or not the second wire was an IFEN wire, and regardless of which wire was involved in the "lead event", it is clear that the IFEN wire's insulation failed. In the absense of this failure, the second wire would have been irrelevant, since there would have been no arc.
At the press conference for the release of the TSB's final report, lead investigator Vic Gerden was asked, "Had the IFEN not been present, would Swissair 111 have crashed?" He refused to answer the question directly, emphasizing the role of the metallized mylar insulation in the spread of the fire. However, I believe the evidence reported by the TSB shows clearly that the answer should have been no. Without the IFEN, there would have been no crash.
I understand that the TSB's position is that the greater good is served by those actions which most effectively reduce future risk ... and since IFT's IFEN posed no future risk, it received lesser emphasis.
This is the ugly politics of air safety at its worst. If the IFEN is to blame, and the IFEN is gone, there is no need for further corrective action. If Gerden had answered the question directly and (IHMO) truthfully, he would have seriously undermined the TSB's ability to influence the safety improvements they recommended.
Our feedback to the Nova producers:
As parents of 16 year old Tara Fetherolf, who was killed in the crash of Swissair 111, we are glad that you calling attention to some of the lingering safety issues related to the crash, but dissapointed that your coverage makes no mention whatsoever of Swissair 111's inflight entertainment system and the story of the regulatory failure that its certification represented.
If you would like to give your internet visitors an opportunity to learn about these issues, you might includle a link to www.swissair111.org. In fact, since your website does inclulde important Swissair 111 related links, it is something less than forthcoming *not* to inclulde the most comprehensive private internet resource on the crash.
You might also consider posting a link to Gary Stoller's feature article on the subject in USA Today: http://www.usatoday.com/money/biztravel/2003-02-16-swissair-investigation_x.htm
Mark and Barbara Fetherolf
NOVA Hits A Sore Spot
Program On Crash Of Swissair 111 May Be Flawed, But It Does Raise Questions
When WGBH in Boston sent me a pre-release copy of "NOVA Presents: Crash Of Flight 111," I ran over to the neighbor's apartment, borrowed a VHS, spun up the tape and heard this:
"I was thinking at the time these things are flying firetraps. I mean, how is it that we can put 200-plus people in an airplane with all this flammable material? This is the tinder waiting for the match."
I came up out of my seat. The comment was made by the one man the airline industry most loves to hate -- David Evans, editor of a weekly aviation safety newsletter. He went on to say, if commercial passenger aircraft were restaurants, they'd be shut down by the health department in a heartbeat.
Hoo boy, I thought. It's another hatchet job on aviation, the likes of which we've most recently seen from CBS Correspondent Bob Orr. Then I watched the rest of the program.
I saw and heard a simulation of the crash of Swissair 111 on September 2, 1998. I heard dramatic music. I saw crying relatives grieve the 229 people lost on board the flight. And, buried in the show business, I heard some news.
To NOVA's credit, it wasn't buried too deep in the sentimental and highly calculated heart-tugs. The news was that metalized mylar, once thought flameproof, isn't. Silicone air duct components also thought fire-resistant aren't. In the 150 or so miles of wiring it takes to fly an MD-11, there could be up to 1500 cracks in wiring insulation -- cracks that, when exposed to the type of condensation typical of the high temperature differences between the cabin of an aircraft and the outside air, could cause electrical arcs. Those arcs can reach 12,000 degrees (F). Although brief in duration, they can be devastating in damaging aircraft systems.
NOVA is a program that bills itself a science show and, to reach aviation neophytes, the producers did what television does best. It grabs you by the collar and slaps you in the face to get your attention. Then it tells you what the producers want you to know. In the case of the CBS story on general aviation security, there was no meat. The NOVA piece, for all its show biz flaws, is filled with facts.
It's also filled with the kind of emotional manipulation that can make a pilot red-faced angry. Words like "flying firetraps" are the kind of words that are virtually guaranteed to scare passengers and threaten an already depressed airline industry. We all know that crews are trained in firefighting techniques, that sophisticated fire detection and prevention technology is employed in many parts of the aircraft and that, in the event of an emergency evacuation, the exits are here, here, here, here and here.
So it might be easy for an aviation enthusiast, industry worker or pilot to dismiss the story. The fact is, there is a preventable fire danger on board most of the world's civil fleet. The wiring. The metalized mylar. The lack of fire detection and suppression equipment in places nobody goes but the A&P -- when he has to.
The program also leaves the story there, as if to hold it out to the flying public and say, "Warning, Will Robinson, warning!" But the story doesn't end there.
The rest of the story is that it takes a lot of time and money to fix the problems raised in the NOVA program. Replacing the metalized mylar insulation could take hundreds of man-hours and cost millions of dollars. Developing, testing, installing and operating additional fire suppression equipment, as called for in the Canadian Transport Safety Board findings on the Swissair 111 tragedy will also take millions and millions of dollars. And if you haven't noticed lately, the airline industry -- along with manufacturers Boeing and Airbus, don't have a lot of spare change to throw around these days.
The NOVA program quotes one NTSB official as saying it took a tragedy of this type to point out the dangers of an in-flight fire to lawmakers and regulators. That's a sad truth. But motivation isn't the issue here. Methodology is the real problem.
If the NOVA story makes you squirm, makes you want to throw shoes at your television and cancel your PBS membership, so be it. We in this business have been battered, bruised and bewildered by events since 9/11. But we are an industry of can-do people. A clear issue has been raised. For once, let's examine the facts, disregard the panic-mongers and address these issues. We can find a better way to insulate wiring and detect faults in that insulation. We can find a replacement for metalized mylar products like MK, MPET and AN-26. We can install better fire protection and suppression systems on board aircraft. All aircraft.
Despite the economic issues we face, despite the uphill battle we have in educating the non-flying public, despite regulation that is often seen as ham-handed, we have a problem folks. And we need to figure out a solution.
Sadly, aircraft manufacturers don't seem willing to engage in this discussion. Aero-News contacted both Boeing and Airbus. We sent both companies copies of our initial story, which was published a week ago. We offered to play portions of the WGBH tape down the phone line. But so far, neither company has chosen to address what will most certainly become an industry hot-button issue in the coming week.
Why? Because on Monday, CNN and Fox News will report the NOVA story. ANN considers itself an aviation-friendly publication. Because it lacks aviation-specific knowledge and experience, the jacks-of-all-trades-masters-of-none general media are more likely to miss important information or center on emotional issues that play to the heart instead of the mind. Both Boeing and Airbus have apparently chosen to miss an opportunity to reach out with the facts to its most sympathetic and knowledgable audience. Now, the general media -- broadcast in particular -- will almost certainly pick up on the most sensational aspects of this story and the voice of industry reason will be shunted aside as an attempt to excuse what will be painted as the unexcusable.
One last thing. In spite of its flaws, I appreciated the NOVA story. Even though it scored about a four on the emotional manipulation scale of ten, It dealt with a timely and important issue in a (mostly) responsible fashion. Sure, go ahead and blow raspberries at the likes of Bob Orr. Be ready to blow some more this week when other media outlets get ahold of the story. But watch the NOVA piece. It's worth your time and will make you think.
CD, Thanks for the article. I find it bizarre that they didn't address the certification issues surrounding the IFEN in their documentary/report. I think it is extremely important that they stress that this plane was a fire-trap and that aircraft flying around continue to be, but to ignore pages and pages of the final report and the probable cause is really odd. Mark spoke with their reporter and provided him with very accurate, extensive information which btw he never even bothered to acknowledge. Very odd. The thing is, not only does it make their information inaccurate (the inference that aircraft wiring was the problem and no mention that the initiating event was on a wire that was improperly added on by Hollingsead- a govt. approved repair station) and incomplete, but if they are trying to alarm the flying public they should have addressed the whole federal government's use of thousands of private companies to inspect and certify airlines' planes and aircraft alterations. There are so many lessons from sr111, and this documentary IMHO has totally missed the boat. I'm left wondering why they would leave this information out and IMHO mislead the flying public about sr111. You also have to wonder why the reporter never spoke to Gary Stoller in light of his factual USA Today articles (links appear on front page of this website) regarding sr111.
Nova's program on Swissair 111 crash investigation is actually an adaptation of a CBC (Canadian Broadcasting Company) film, directed and written by Halifax-native, Howard Green, and was a co-production of CBC-TV's "The Nature of Things" and Swiss National Television. It aired in Canada on April 3, 2003.
During the investigation, "embedded" reports and film crews documented the investigation in detail, but were "sequestered" until the publication of the TSB's final report.
In Canada, the film was aired, followed by a panel discussion led by Nature of Things host David Suzuki. Members of the panel included David Hall, former head of the U.S., other air safety advocates and me. The Nova version of the program presents an edited version of the film along with commentary by David Evans and others.
The sound bites that have been most quoted in the pre-broadcast publicity for the show are exclusively from the new Nova commentary ... which is no surprise, because Mr. Green's film is anything but controversial. It is primarily about the techniques and the science employed by the TSB investigators - far more than it is about the results.
The commentary, on the other hand, has little to do with the film, and everything to do with the conclusions of the investigation (wherein lies the controversy). What the TSB concluded was that aircraft material flammability standards are inadequate and fire detection and suppression are nonexistent. However, I doubt that most viewers would even come away from the film understanding this much without someone saying something along the lines of "flying firetraps".
But if airplanes are full of tinder and there are no fire extinguishers, the question still remains, what about the match? What started the fire? The Nova pre-broadcast coverage discusses the hazards of aircraft wiring. Yet strangely, there is little in the TSB's report that indicts aircraft wiring in general, whereas there is much that specifically indicts the electrical wiring of the inflight entertainment system (IFEN). Why is the IFEN getting the soft-soap treatment these days? Might the experts, many of whom are highly critical of Kapton wire insulation, find the IFEN uninteresting because it didn't use Kapton-insulated wiring? Or is there some other reason why the broadcasters, the media and the FAA don't want to confont this?
In any case, the TSB places greater emphasis on the MPET insulation. In other words the tinder is the cause, the match is a risk. If one lights a match in a room full of tinder and starts a fire, is the cause of the fire really the tinder? One could argue that both are required and so they are both elements of the cause. But why would one blame the tinder and excuse the match?
In the case of the TSB's report, the answer is clear. If the match is the cause, or even the cause in equal part with the tinder, then getting rid of the matches solves the problem. No further action is required. And that's exactly what the industry would do, since disposing of the matches is a lot cheaper than getting rid of the tinder.
For safety's sake and the greater good, this view has merit. Even if it was the IFEN's wiring that caused the fire and there are no more IFEN's, any electrical wire *can* arc. It happens. Better to take away the flammable material and install fire suppression systems.
Unfortunately, what's lost in the fog is the truth of why Swissair 111 crashed. And ironically, in spite of the TSB's best efforts to spin the story so as to influence the course of safety improvements, things remain much the same as ever.
All in all, itï¿½s a pretty sad commentary - and itï¿½s unfortunate that Novaï¿½s treatment of the material fails to confront the true scope of the issues involved.
The Nova special on 110/111 was very enlightening. I had no idea about the internal world of the airplane, how behin the panelling there are electrical wires sandwiched between flammable mylar... and, no fire extinguishers in the cockpit nor even a smoke detector. That is just crazy! I have extinguishers and smoke detectors throughout my house.
My eyes have been really opened to write letters asking congress to please mandate laws to force commercial airlines to equip all fleets with extinguishers and detectors.
A response we received to Mark's comments to Nova- a form letter (see Mark's comments below):
Dear Mr. and Mrs. Fetherolf,
Thank you for your message. Weï¿½re glad you were pleased with the program. We appreciate your comments and will share them with the appropriate NOVA staff. We regret that, due to the large volume of mail, we cannot respond individually to your questions.
If you want to find out about any future NOVA programs or Web sites that may be of interest to you, feel free to subscribe to our e-mail list. If you subscribe, youï¿½ll receive an e-mail message whenever a new NOVA program or Web site becomes available. To subscribe, reply to this e-mail and write "subscribe" in the subject heading or visit
Thanks again for sending in your thoughts.
I saw on an aviation discussion board (Yahoo) another family member found it strange (he referred to it as a whitewashing) that the IFEN was barely mentioned in the Nova documentary.
Havenï¿½t yet seen the NOVA treatment but ï¿½.
Casting aside all the (albeit important) secondary causes and underlying systemic abuses that led to Swissair 111, we come down to the bottom line that fire in the air is a killer. We can take all kinds of HAZMAT precautions, ban smoking, fix fuel tanks so that they won't explode and have cargo-bay fire suppression - but every time an airplane takes off it carries "the makings" for a fire in its many hundreds of miles of wiring and thousands of electrical components. For many long-haul ETOPS aircraft there will be no Land ASAP solutions when the day comes. The scope for simple failure or human error or just "fair wear and tear" is there. No-one can guarantee that airplanes won't age or deteriorate through hard use - or that heavy maintenance will turn up all the glitches that reside within it. Hydraulic systems normally have triple redundancy and if they fail they normally do so via a leak that leaves a puddle (at least) or shows dropping pressures - and so hydraulics don't have a nasty reputation for traumatic events. Wiring on the other hand doesn't have any redundancy and it is subject to clandestine failure. It sits there chafing and vibrating with the natural high frequencies of flight for thousands of flight hours - and then fails without warning.
Apart from the TWA800 fuel-tank explosion scenario and the explosive mix in Valujet 592's holds, most "fire of unknown origin" electrical happenstances follow a fairly low key development (or at least it was low key for most pilots before SR-111). The smell of acrid fumes or sighting of wisps of smoke starts a search process via a drill. And (as you will have seen in many reports) success often depends upon there being a concomitant system failure (windscreen cracks or ATC reports your transponder return is lost or maybe the radio in use quits). Rarely will that avionic piece of kit be seen to be smoking because that resides in the racks of the E&E bay below the cockpit and it's only a control panel there on the centre console (or side pedestal) beneath your hand. So not every failure will manifest itself as smell or smoke beneath your nose. Evidence will be hard to come by and (per SR-111) the real problem can reside elsewhere in a component or wiring loom that's quite distant and tucked away behind panels and thermal-acoustic insulation blankets.
The MD-11-99-04 Long Beach Pilot Bulletin by Tom Melody (Chief MD-11 Test Pilot)
LINK HERE admitted that the MD-11 smoke checklist would take at least 35 minutes and yet possibly still be inconclusive. They can't change that situation because the whole search procedure revolves around the infamous Smoke/Elec/Air Switch that depowers and repowers busses via the smoke checklist.
The flawed expectation is that a pilot will be able to pick the S/E/A selection that will make the smell go away. Well that's highly unlikely as acrid fumes get into your mouth, eyes and nostrils and they just don't go away. After SR-111 the informal solution was Land ASAP but that has its own attached perils and as per SR-111, the pilots might find that even if they do make it to finals, the a/c may be in poor shape (no flaps, slats, brakes etc).... and still full of fuel and overweight for landing.
Well perhaps that's why there's only about a dozen MD-11's still flying pax now and the rest are cargo converted or parked in the desert awaiting that. But it's not only an MD-11 problem. It's a problem of time and configuration and the power remaining on the wire while the situation deteriorates. What is the answer to the lack of electrical redundancy that causes pilots to piece-meal de-select busses and gradually power down whilst the power remains on the wire and fire is given its best chance (time elapsed) to propagate and take hold?
The answer is here and
here (and in the associated IASA links). It is a system development that has been mentioned publicly in writing by ALPA reps (and even ALPA's fire and cabin safety man) as a possible solution (and ALPA doesn't say such things lightly).
The bottom line for Swissair 111 is whether or not the absence of electrical system redundancy and lack of an alternate fallback configuration is acceptable. All the other reasons behind SR-111 are still extant - the lousy build standard in a climate of industrial unrest, the dangerous aromatic polyimide wire used, the electrical system design philosophy, the tacked on IFEN, the SR training and simulator emphases, an airline that believed its own PR hype and a nation that now has to eat its own words and publicly go in search of where their global air safety reputation got derailed.
Whenever I think about Swissair 111, and that's quite often, my thoughts and pity go to the pilots who were stuck within a lousy system with lousy procedures and tried to make the best of it. The fact is that, thanks to unsubtle changes in circulation as the electrical configuration was switched, they were always chasing a will o the wisp - and finally Fate and Destiny caught up with them all. It didn't have to be that way. When you look for the real reason for Swissair 111, look first to the prime mover - without which there'd not have been an accident. Then think about the system described above and the scope offered by that option.
Thanks, Dirk, for your excellent insight. I think you make an important point that I'll try to reiterate.
Aircraft fires are, in some respects, like fires encountered elsewhere. The first steps are detection and supression (presuming that prevention measures have already failed). But for in-flight fires, there is another key element: keeping the aircraft flying while the fire is dealt with!
If the electrical wiring in your house caught fire, you would pull the main circuit breaker, call the fire department and evacuate. None of these actions are possible in-flight. The Virgin Bus provides flight-critical systems with a backup power source so that all of the primary electrical circuits can be shut off.
The TSB of Canada's report on the crash of Swissair111 makes a number of recommendations related to in-flight fire:
quote:While the TSB's analysis cleary points to risks associated with electrical systems, it does not go so far as to recommend a specific approach (e.g. the Virgin Bus) to the problem of maintaining power for flight-critical system. I think this is partially the result of their view that flammability standards for many materials used in aircraft manufacture are inadequate, and electrical systems are but one potential source of ignition.
The TSB's report did cite an FAA policy guideline memorandum developed in the wake of the SR111 crash:
quote:Of course the right answer to the problem of in-flight fire is a combination of prevention, detection, supression and fault tolerance.
While I'm sure we can all agree that an ounce of prevention is worth a pound of cure, it is crucial that the problem is attacked on each of these fronts. It seems that the engineering and regulatory community are of the opinion that potential faults should be "engineered out". While this is a worthy goal, it is ultimately unattainable. Of course, each individual aircraft component should be engineered for the most reliable and safest possible operation, but should also be part of a fully fault-tolerant overall system.
This program is being broadcast again on PBS Tuesday, March 1 at 8 p.m.
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