Air France 358 crash was avoidable

First published 03 October 2005.

But lazy, half-assed reporting was not.

Sunday’s Toronto Star had a nice three-page story about the September 2nd incident involving Air France 358 (web version here).  As citizens of this city are no doubt aware, the A340-313X arrived at Toronto Pearson’s Runway 24L in the midst of a severe thunderstorm.  The aircraft did not touch down until almost halfway down the 9,000ft runway, and it did not manage to stop, but ran off the end of the runway and went careening down into the Etobicoke Creek ravine.  The plane caught fire and the composite-based fuselage was almost completely destroyed, although no passengers were killed.

The Star leads off its coverage with a splashy front-page colour photo of the burning aircraft, with the bold headline “THIS COULD HAVE BEEN AVOIDED: An exclusive investigative report into this summer’s Air France crash at Pearson“. CTV News also summarized the story in their web edition here.  Naturally, I was eager to see what Star reporters Scott Simmie, Kevin McGran and Catherine Porter had to say about it.  I thought I was going to hear interesting anecdotes from current A340 pilots, runway design enhancements from GTAA staff, a discussion of the typical decision tree when flying in severe weather, and speculation on what might have occurred in the cockpit during the event itself.

What I got instead was at least one full page devoted to the detailed story of two particular passengers, some idle speculation from lawyers handling the class action suit, quotes from exactly two pilots, four specific recommendations for field improvements to the airport, blasé rebuttals from a GTAA official that at least one of the runway improvements may not be effective in winter, and some very, very sloppy reporting.

I am disappointed in the Star‘s coverage for a number of reasons:

1) Focusing exclusively on airport safety measures and not pilot decision support systems.  Here are the Star‘s four recommendations:

A) Terminal Doppler radar.  Doppler radar allows meteorologists to see inside the storm structure and determine where wind shear is likely to occur.  This predictive function can be automated, with alerts passed to air traffic controllers when wind shear has been detected (or likelihood of it is very high).  ATC would then pass on the warning to inbound aircraft, who would then make decisions about the wisdom of an approach into such conditions.  Pearson International does not have its own Doppler radar but instead relies upon the Environment Canada doppler system based in King City, Ontario.  While this is a great suggestion and Pearson ought to have its own terminal Doppler radar in any event, it does not take rocket science to predict the occurrence of unsafe wind shear within a thunderstorm.  That assumption is routine for GA pilots whose smaller aircraft do not carry their own weather radar.  Although large commercial aircraft regularly fly into severe weather conditions, private pilots in smaller aircraft generally do not.  Why?  Because there are certain life-threatening risks associated with doing so, and you learn that in ground school before they ever let you near your very first prop-driven, piston-engined aircraft.  You don’t need Doppler radar to figure out that thunderstorms are inherently dangerous to flight.

B) Grooved runway surfaces.  Cutting small 6mm grooves, spaced 24-38cm apart, into a runway’s surface can help drain water and prevent hydroplaning.  The grooves are perpendicular to the runway’s direction of travel.  The FAA requires grooving of concrete and asphalt runway surfaces, but Transport Canada does not.  Pearson’s concrete runways were grooved at the ends in the 1970s, but its current asphalt runways are not.  Transport Canada believes the grooving technique may be effective in the summertime, but results in increased maintenance and marginal effectiveness during the winter.  Note also that TSB lead investigator Real Lavasseur has publicly cast doubt on speculation that hydroplaning was a decisive factor in the AF358 incident.  This did not stop the Star’s crack team of reporters from quoting a retired pilot and other experts who speculate that hydroplaning did occur and was in fact a decisive factor in the erosion of AF358’s braking performance.

C) Engineered Material Arresting System (EMAS).  ICAO recommends a 1000ft overrun area and the end of each runway, but not all airports have enough real estate to accomodate large overrun areas.  EMAS mitigates that limiting factor to a degree.  It is special, crushable concrete placed at the end of a runway in the overrun area, designed to crush under the weight of an aircraft, but support the weight of emergency vehicles.  EMAS slows down an overrunning aircraft rapidly by absorbing the aircraft’s inertia while denying its wheels traction, much like a car trying to drive on loose sand.  Airports whose runways end in a body of water have been most of the early adopters for this technology, and it is credited with some impressive saves.  Since the EMAS concrete is very porous, the GTAA has questions about its effectiveness in winter.  In wintertime, the EMAS concrete is likely to fill with water and freeze, increasing its structural strength slightly and raising its weight threshold.

D) Covering over the Etobicoke Creek.  Putting any kind of effective overrun area (EMAS or otherwise) on the 06-24 runways would involve covering over a portion of the Etobicoke Creek ravine.  What the Star doesn’t mention is that covering the ravine and installing a 1000ft overrun area without EMAS would be a big-ticket Bad Idea, as Highway 401 angles northward west of the runway end.  Any aircraft travelling fast enough to have a significant overrun on Rwy 24L may just end up on the 401 westbound collector lanes.  If we install any kind of major overrun area on the 06-24s, it has to have some kind of inherent decelerative properties, like EMAS.

In the Star‘s world, the installation of these four technical solutions at Pearson International would have saved this flight.  And to its credit, the paper’s discussion of the possible field improvements is informative, largely factually accurate and relevant.  But these systems (with the exception of Doppler radar) are essentially a last-minute fail-safe.  Technical means provide some buffer from bad decisions made in the cockpit, but on their own they are utterly inadequate to prevent future tragedy.

For these fail-safe systems to come into play, your flight crew must already have shown questionable judgment and landed under marginal weather conditions… on a very wet runway… without enough room to stop.  With all due respect to the Star, air travellers generally want the avoidance of disaster to consist of more than last minute, on-the-ground airport and runway improvements.  There is no ground-based system which can definitively prevent errors in judgment.  The best flight management systems in the world are up there in the airplane with you, housed inside the skulls of the flight crew.  Getting the right information into that grey matter, at the right time, is critical to flight safety and the best way to avoid screwups.  If your flight crew makes a series of bad enough calls, even the world’s best weather detection systems and a three-mile runway with a thousand-foot EMAS overrun zone can’t help you.  You have to catch each little questionable decision long before they collectively add up to something approaching disaster.  This is generally well ahead of the point where the flight crew is staring at the rapidly approaching opposite end of the runway.

And what about other safety measures, like distance-to-go markers.  In addition to grooving the runway and installing this EMAS overrun zone stuff, wouldn’t it be a whole lot easier and cheaper to give pilots the tools to know what’s left in front of them?  Then they can make their own decisions about whether a full stop or touch-and-go is viable.  Why make them guess and wait for the concrete embrace of Nanny GTAA’s overrun zone?  They are pilots for heaven’s sakes, trained and accustomed to multi-tasking — talking to ATC, maneuvering the aircraft, fiddling with the FMS and avionics all at the same time.  They are not your typical poorly-trained civilian driver who can barely manage to safely maneuver his or her commuter vehicle down the highway while talking on a mobile phone.

2) Non-explicit accreditation of the two quoted pilots.  Neither were Air France pilots, and neither were credited as being currently or formerly rated to fly the A340.  I’m going to excuse the first pilot because he was quoted in context as the head of the Canadian safety branch of the Air Line Pilots Association, and he was speaking about weather detection capabilities at Pearson.  Although he only flies regional jets and turboprops, he has additional knowledge and a role dealing with air safety in a professional pilots’ organisation.  That’s a reasonable linkage.  The second pilot, however, is credited only as being retired from Air Canada, and he was speaking about this particular landing incident.  Look, guys, I know you’re just mere reporters but not all pilots are created equal.  Different airlines have slightly different operating procedures, even for the same type of aircraft.  Not all pilots are qualified to fly every aircraft in the airline’s inventory.  Some pilots are captains and some are FOs (first officers).  Some have additional training duties, like checkrides and pilot qualification.  All of these things have a bearing on the relevance of their commentary to a news story like this.

For instance, my own experience in single and twin piston-engine general aviation aircraft does not make me an expert witness in terms of multi-engine turbofan-powered commercial air transports.  I know what I know, but more importantly, I know what I don’t know.  If you want to know about a particular aircraft’s performance limitations, then talk to someone qualified in that aircraft type, plain and simple.  Don’t find the first off-duty guy with a uniform and ask him to comment about flight systems, avionics and procedures he’s not familiar with.

What made the retired Air Canada pilot worth talking to?  Special training?  Involvement in a similar accident?  Familiarity with Air France’s training doctrine and procedures?  Similar tastes in the choice of neighborhod pub?  His kids play with yours in day care?  Where does his expertise, aside from being a generic ATP-rated commercial pilot, bear relevance to this incident and your story?  Anyone?  Anyone?  Bueller?

3) Failing to follow up on obvious questions.  Leave the fluffy human interest crap at home.  I’m not interested in the devout Iraqi Christian woman who prayed through the whole flight and busted her femur getting out of the burning plane.  Thrilling to some, no doubt, but leave the Reader’s Digest “Drama in Real Life” tear-jerkers for Oprah.  The whole article is supposed to be about how THIS COULD HAVE BEEN AVOIDED, remember?  Where was your editor when the three of you decided to phone in this under-researched story?  Ask some real frickin’ questions for a change:

  • The Star mentions the unsourced Figaro story I mention here, and then goes on to say that the twelve-second delay in reverse-thrust deployment may have been “software related”, even though Airbus’ safety circular after the incident noted no software problems.  This is the simpleton’s method of saying that all of the thrust reverser interlock conditions (wheel rotation speed, main gear compression, throttle setting, radio altitude) may not have been met.  Airbus would not have indicated any software problems because the software is not at fault — even if hydroplaning occurred, no one is going to recommend disabling the interlock criteria for wheel rotation speed — it was operating properly as designed.  Disallowing reverse thrust because not all interlock criteria are present is not a fault with the software (which can not detect a hydroplaning condition) — but with the pilots, who are supposed to assess the risk of hydroplaning long before touchdown, and adjust their landing and rollout procedures accordingly.
  •     * What’s really important is not whether or not the reversers engaged twelve, ten, or even two seconds after touchdown.  Reversers will slice off, at most, 11% of the landing distance on a very wet runway.  Other conditions, such as weather and runway contamination (water, oil, etc.) can totally nullify any landing distance reduction from operational thrust reversers.  Significant tailwinds, for instance, can increase the landing rollout by as much as 24%.  Didn’t any of your pilot sources tell you?  Perhaps none of them were rated to fly the A340, were they?  So I guess they wouldn’t be able to approximate the landing weight of an A340 flying a transoceanic LFPG-CYYZ route with 309 souls (and luggage) aboard, nor estimate precisely how runway and weather conditions affect the length of the A340’s landing rollout.  You know what remedies lack of personal knowledge? Research.  Where the hell was yours?  You could at least find the last reliable METAR, and figure out how much of a tailwind there was.  Would reversers (delayed or otherwise) have made any impact at all, given the late touchdown, tailwind and poor runway conditions?
  • Why did the crew elect to execute an approach when there was significant storm activity on the field?  Significant convection activity (like cumulonimbus clouds [CBs] and lightning) are reliable indicators of the presence of wind shear — i.e. rapid wind direction or velocity changes.  Wind shear is not exactly a new phenomenon to pilots, especially those with enough experience and training to hold an ATP rating and type-certification on multiple varieties of turbofan-powered airliners.  GA pilots are generally advised to stay away from an airport that is showing cumulonimbus (CB) activity within 15 nautical miles of the field.  What sort of restrictions or advisements exist for commercial aircraft?  Were any of these in effect at the time?  What are Air France’s guidelines for approaches into marginal weather.  What, if any, are the decision criteria for diversion to an alternate?
  • Newer A340s, like the A340-600, carry enhanced weather radar with predictive wind shear detection capability.  These systems warn pilots as much as a minute in advance of expected wind shear activity.  Was the A340-313X fitted with these systems, or not?  What sort of weather detection capability (besides the aircrew’s Mk I Mod 0 eyeballs) does it have?  How would these systems have helped or hindered the aircrew in their decision to divert or execute a full-stop landing?
  • The retired pilot indicates that landing with 40% of the runway behind you is a classic “Don’t do it” situation.  The preferred solution to a rejected landing is applying power (TOGA or take off/go around thrust), executing a touch-and-go followed by the missed approach procedure.  Since an aircrew cannot see how much runway lies behind them, how do they know how much runway remains in front?  At what point does the landing become rejected and TOGA thrust applied?  What decision factors lead an aircrew to make this call?  Does Air France include these scenarios in routine simulator drill?  Do any other airlines?  How frequently do they practice it?  How many flights, on average, ever execute a touch-and-go?
  • One of the lawyers suing the airline speculates the plane was low on fuel and had to land or risk fuel exhaustion.  What is the basis for this claim?  Has the lawyer ever heard of a thing called “reserve fuel”?  Does the laywer even know the regulations for flight and fuel planning for commercial transoceanic flight?  Has Air France or any of its aircrews violated any of these fuel planning or must-divert regulations in the recent past?
  • The Star mentions the loss of the anemometer, which gives wind speed and direction information to air traffic control (and hence also to the pilots).  Did air traffic control pass on the anemometer failure to Air France 358, and how would this have affected the aircrew’s land-or-divert decision?  What level of equipment failure is sufficient to jeopardise flight safety and/or shut down the runway?  What are Air France’s regulations for landing at fields in severe weather that have non-operational weather detection gear?

I am just a plebian, non-ATP-rated civilian but I have managed to answer a few of these questions on my own, here on this blog.  I could literally write volumes about this stuff.  If I somehow — horror of horrors — looked upon blogging as a journalistic effort I might even be motivated to write more, but I’m not paid to do this and frankly the idea of being a reporter does not and never will excite me.  I like to do things, not write stories about other guys doing things.  Most of my pilot pals fly GA (general aviation), and the commercial guys I know mostly fly Boeings.  And none of them work for Air France, so I will never be able to answer all the airline-specific questions.

But some folks do get paid to write stories, and among those people are the ones who forgot to ask all sorts of pertinent questions in the course of this so-called investigation.  In the Star‘s case, it took not one but three J-school grads to forget or avoid asking all of these questions.  Yet they still managed to milk this weak article in a major Canadian daily for a full three pages, and many other media outlets picked it up and ran with it — without asking questions of their own.

I stopped reading the Star a while ago, because sometimes while scanning a half-baked, poorly-researched story I could actually feel a net loss of brain cells.  News coverage is supposed to inform the public, not make us dumber for having read it.

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