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Canadian air travel roundup

Terminal 3 Pearson Airport, originally uploaded by Allan P1.

A somewhat random collection of bullet-points from the world of Canadian air travel.

  • Air France caves in to the class action suit brought by passengers of AF358, and settles for CDN $11.65 million.  The seriously injured (mentally or physically) will receive a maximum $175,000 payout, while the uninjured will receive the minimum payment somewhere between $5,000 and $10,000.  I remind readers that the AF358 incident was a runway overrun in which there was no loss of life amongst its 297 passengers and 12 crew, and in which the biggest financial loss was borne by the airline itself, which had to write off the aircraft completely.  Suits still pending: Air France, suing GTAA and Nav Canada for the loss of an aircraft; GTAA, suing Air France for the cost of post-accident environmental remediation; and one passenger (who opted out of the class-action lawsuit) who is suing all parties.
  • Airline and airport staff are not entirely clear on the specifics of the nonsensical and hastily composed new carry-on baggage regulations, and kind of making it up as they go along.  Big surprise there.  Your correspondent has a suggestion, based upon years of experience watching his wife haul around purses of various sizes (the largest of which could have discharged a tank platoon on Juno Beach in 1944).  A “small” purse is one that can accommodate your wife’s wallet and phone.  A “large” purse is one that has any excess payload capacity beyond that.  As far as laptop bags go, they are all “large”, even if made to cart around a 13″ netbook.  There is no such thing as a small laptop bag, because people cram them full of junk.
  • Farouk of the Flaming Underpants had fantasies of being a holy warrior, says the Toronto Star.  Well yeah—that’s what radical Islamists do.  If he didn’t want to wage jihad against the Great Satan, he probably would have sat down and watched a football game instead of fabricating explosive Y-fronts.
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Progress, of a sort

08403v hanno, originally uploaded by A30yoyo.

Professor Karl D. Stephan, author of the Engineering Ethics Blog, shares an interesting observation while reviewing Air Accident Investigation (3rd edition, 2006) by Mr. David Owen.

I was intrigued by a photo of what has to have been one of the largest biplanes ever built, a Handley Page H. P. 42 flown by Imperial Airways in trans-Channel service in the early 1930s. It was about four stories high and had four engines clustered around the fuselage. Owen’s point in including it was that although there were plenty of accidents back then, early commerical aviation was operated so conservatively that in ten years of use, the H. P. 42 never lost a passenger to a fatal accident.

All this changed after World War II, when jet aviation and economic growth transformed the flying public from a few privileged individuals into hordes of airborne bus passengers. Higher speeds and long over-water flights raised the cost of in-flight mechanical failure to the point that surviving a commercial airline crash was a dubious proposition at best.

— Stephan, Karl D.  “Air Accidents in Perspective.” Engineering Ethics Blog, 16 November 2009.

There are a huge number of factors that contribute to increased lethality in crashes of modern jet aircraft.  In addition to increased gross weight, payload, speed, and frequency of over-water flights, there is the nature of the aircraft themselves.

Airports of the day rarely had asphalt or concrete runways, so the H.P. 42 had to be able to operate from semi-prepared grass or dirt airstrips in the middle of nowhere.  Its takeoff ground roll was just over a thousand feet, and its maximum takeoff weight (MTOW) was around 28,000 pounds.

Today’s jet airliners are not capable of operating from 1,200 foot grass strips on a routine basis.  They weigh several times as much as an H.P. 42 (the 737-300’s MTOW is 124,500 lbs), so their takeoff roll is necessarily much longer.  Their gear is not designed to handle operations from rough fields; they need asphalt, concrete, or (with special tires and gear kits) gravel.  Your odds of randomly finding 1000 feet of open grass or dirt in any given spot in Central Europe, Africa or Southern Asia are pretty good compared to your odds of randomly finding 4-5,000 feet of level asphalt or concrete that can also withstand the weight of 125,000 pounds of airliner landing on it.

All that said, jet travel is here to stay, and in spite of the increased risks, it has also grown much safer.  I’d be interested in reading Mr. Owen’s conclusions for myself, so I shall check with the library to see if they have a copy.

SEMI-RELATED: Professor Stephan doesn’t post very often, perhaps once a week at best, but his entries are full of cogent thoughts.  I also enjoyed this post about toxic drywall from China, and what the likely outcome might be for banks and consumers stuck with such toxin-infused homes.  I look forward to reading more.

Category: Aeronautics, Industria  Tags:  Comments off

How to End your Flying Career

nwa188_flightpath

Path of Northwest Airlines 188, overflying and returning to KMSP

Former Hornet driver Neptunus Lex notes two unfortunate (and in one case, unfathomable) occurrences from the world of commercial aviation:

  • Delta Flight 60 from Rio de Janeiro to Atlanta landed not on the assigned runway 27R, but on parallel taxiway M.  (See the layout of Atlanta/Hartsfield Intl Airport [KATL] aerodrome here.)  The aircraft touched down at 0605 Eastern Time and there were no injuries, but the night lighting for runways and taxiways was active—runways are lit with bright white lights, taxiways are lit with blue lights.  NTSB is investigating.  For those in the know, Atlanta is Delta’s major hub in the eastern United States, so it’s hard to imagine how both pilots might be unfamiliar or unaware enough to mistake the taxiway for the runway.
  • Northwest Flight 188 from San Diego to Minneapolis remained at cruise altitude (FL370) and overflew its destination by 150 miles, out of contact with air traffic controllers.  The aircrew claimed they were having a vigorous discussion of airline policy and completely missed the TOD (top of descent) marker on their ND (nav display), the repeated calls from air traffic control, and so on.  NTSB has claimed the FDR and CVR for its investigation, but since the CVR only retains the last 30 minutes of activity, I doubt whether they will recover much more than the sounds of a crew in touch with ATC, getting clearances and vectors for their approach, and so on.
Category: Aeronautics  Tags: , ,  Comments off

Air France 447

An Airbus A330-200, flying from Rio de Janeiro to Paris with 228 people aboard, vanished over the North Atlantic just after crossing the equator.  It’s always a tragedy when something like this happens.

Some people, including an Air France spokesman, ruled out terrorism and initially speculated that the mishap was due to lightning, which is so fatuous and misleading as to verge on intentional falsehood.

An A330 flying at a cruising altitude of FL350 or 35,000 feet has a pretty good idea of where the bad weather can be found.  First of all, it is flying above all but the highest cirrus (and cumulonimbus) clouds, so the lightning-producing convection activity of tall, anvil-topped cumulonimbus clouds stands out like a beacon.  Even when they are surrounded by other clouds, a line of thunderheads tend to be obvious and easy to spot with the naked eye.  And the A330 has weather radar, naturally, which does a good job of spotting clouds, convection and lightning activity within the storm that the Mark I eyeball might miss.

In order to even have a shot at being lost due to lightning, the pilots would have to have ignored their weather radar (or turned it off), ignored the evidence of their own eyes, and decided to fly into convective storms without trying to “thread the needle” and find a way around the worst of it.  Ignoring passenger safety and comfort along the way.  And that is not even considering the many backup systems available to the aircraft and pilots should lightning happen to fry something.

They may well have gone down due to the inherent risks involved in flying heavy at high altitudes, meaning that the aircraft had less margin of error between cruise speed and minimum safe manoeuvring speed. In the convective turbulence of a thunderstorm, you can lose a lot of airspeed due to the buffeting of the weather, and that may all add up to a rapid and unexpected departure from controlled flight.

But the only way that lightning could down an A330 and cause structural failure too fast for pilots to react is by de-bonding one of its composite empennages or flight control surfaces.  Or in layman’s terms, putting so much voltage into the carbon/epoxy vertical and horizontal stabilizers that they vaporise or explode, leaving the aircraft with no way to control its attitude or altitude.  This scenario is possible, but not overly likely, as A330s (as well as every other type of airliner with composite structures) get hit by lightning on a fairly regular basis—on average once every 3 years—without their rudders or elevators going kaboom.

This is not to say that terrorism is the answer.  But the true cause occurred so suddenly that the aircrew had no time to issue any distress calls, and the resulting condition put such stress upon the airframe that, according to ACARS automated telemetry, it came apart on the way down.

UPDATE: I should point out that a lot depends on how far apart those ten ACARS error messages were transmitted.  If the electrical failure came first, followed by the remainder several minutes later, it is reasonable to suppose a lightning strike occurred and took out some vital system (perhaps the plane’s radar, as supposed by Miles O’Brien in this Reuters post).

If all ten failures occurred within a very short time period, with no significant delay between them, then something catastrophic happened at altitude and took the plane apart.

UPDATE 022105Z JUNE 2009: Interesting unconfirmed details from the Aviation Herald website (via commenter Tailspin at Neptunus Lex).

New information provided by sources within Air France suggests, that the ACARS messages of system failures started to arrive at 02:10Z indicating, that the autopilot had disengaged and the fly by wire system had changed to alternate law. Between 02:11Z and 02:13Z a flurry of messages regarding ADIRU and ISIS faults arrived, at 02:13Z PRIM 1 and SEC 1 faults were indicated, at 02:14Z the last message received was an advisory regarding cabin vertical speed. That sequence of messages could not be independently verified.

The whole Aviation Herald post is worth checking out, lots of good information there, including airway routes and infrared weather images.

UPDATE 040909Z JUNE 2009: Reuters is reporting that the debris field included a large fuel/oil slick on the ocean surface, which in the estimation of the Brazilian Defence Minister rules out a fire or explosion.  That is pure nonsense.

I’d say it indicates that one of the wings came down more or less intact, and that’s about it.  If both wings and their tanks had come apart at cruise, the fuel would probably not be a large 20km-long slick; it would be many smaller droplets spread out over a large area.  I also don’t see how the presence of the slick would rule out, for example, a fire in the cockpit (a la Swissair 111) or detonation of an explosive near the rear pressure bulkhead, which could cause separation of the vertical or horizontal stabilisers (a la Japan Air Lines 123) and render the aircraft uncontrollable.

The A330-200 has a few variants, one with a center fuel tank and one without.  Tanks common to both variants would be inner and outer wing tanks, wingtip vent tanks, and a trim tank in the horizontal stabilisers.  Tank location diagram can be found here.

None of this is proof that a fire or an explosion did occur, but neither is it wise of the politicians to rule out such a possibility while the most significant data and materials lie on the ocean floor.

UPDATE 060404Z JUNE 2009: So basically everything you have heard about AF447 from the media is wrong.  Except that the plane was flying from Rio to Paris, didn’t make it to the destination, and 228 people died.  They are now saying that the 20km-long oil slick came from a ship, not the aircraft.  And a wooden pallet reported to be payload from the aircraft is not actually from the aircraft, either.  Well done, fellas.

UPDATE 101146Z JUNE 2009: Reader Ghost of a flea emailed this article which contains an interesting nugget of information:

Unease over the A330 was strengthened by charges from the Alter pilots’ union that Air France had covered up problems with the airspeed instruments. It emerged this week that the airline advised pilots on November 6 last year that there had been “a significant number of incidents” in which false speed readings had upset the automated flight system — in the manner that appears to have happened on Flight 447.

These incidents, from which the crew were able to recover, occurred at cruising altitude, said the two-page circular. As a result of the false readings — apparently caused by ice clogging up the pitot tubes — the automatic pilot disconnected. The data from the doomed Airbus last week reported the same sequence, but the pilots were unable to regain control. A parallel is being drawn with an incident last October in which a Qantas A330 dived inexplicably under the command of its flight system, seriously injuring several passengers. James Healy Pratt, a lawyer with Stewart Law, a London firm handling the Qantas incident, said that the sequence of events was the same, with fluctuating airspeed indications apparently causing the auto-pilot to disconnect.

— Charles Bremner.  “Air France pilots told not to fly Airbus jets after Brazil crash“, London Times, June 10th, 2009.

UPDATE 151221Z JUNE 2009: No explosion, but an in-flight structural failure.

Post mortems carried out on 16 of the first 50 bodies found floating in the sea reportedly have no trace of burn marks or smoke, supporting the theory that the accident was not the result of a blast.

…Although an explosion is unlikely, investigators believe flight AF 447 broke up in the air because of the location of victims’ bodies found in the water.

Two trails of bodies were discovered, more than 50 miles apart, which suggests the jet broke up before impact.

They had no water in the lungs – which would have indicated drowning.

— Henry Samuel.  “Bodies of Air France flight 447 victims show no signs of mid-air explosion“, London Telegraph, June 15th, 2009.

Colgan Air 3407

There has been some good blog coverage of the Colgan 3407 accident lately.  For a perspective on the Catch-22 finances and schedules that the regional airlines (and their pilots) find themselves in, read Aviation Mentor‘s terrific post.  For an in-depth examination of the FDR (flight data recorder) and CVR (cockpit voice recorder) data, see Blogging at FL250.  Probably the best overall description of the events leading up to the fatal crash, far better than anything you will find in bowdlerised media accounts, whether print, web or television.

It’s hard to know what to make of this incident, as the accounts you get in the media inevitably focus on the sensational (CVR, shrieking final moments, etc) as opposed to the instructive (FDR).  What has become apparent out of the data is that the aircraft didn’t suffer a tailplane stall so much as an ordinary (wing) stall, something pilots all over the world are taught to recover from by pushing the nose down and increasing the throttle.  Yet the captain of Colgan 3407 did the opposite, and it’s not entirely clear why.  Media accounts paint him as inexperienced at best, and at worst they hint at several failed checkrides and come nigh to declaring him incompetent.

My own sense is that one doesn’t get past a PPL, instrument rating, night rating, commercial rating, multi-engine rating, ATP, type rating, several FO checkrides and captain checkrides by being an incompetent boob.  It strains credulity.  Which is not to say that pilots can’t occasionally be stupid, but they are not habitually stupid.  So how to explain pulling up on the yoke when standard stall recovery is to push the yoke forward?  A panic reaction?  Or did the captain mistakenly believe they were experiencing a tailplane stall (whose recovery procedure is to pull up), only to belatedly realise that it was a wing stall—but by that time, all manoeuvring altitude had run out.

The “how” is readily apparent from the FDR, but it’s hard to answer the “why” without having the aircrew able to answer for themselves.

UPDATE:  Sam at Blogging at FL250 cranks out another home run with his latest post.  In it, he unlocks the mystery of why the captain might have acted contrary to standard to stall recovery procedures.  The short version is that the Practical Test Standards for the ATP rating do not require realistic simulation of an approach or takeoff stall, where the aircrew is distracted.  This allows airlines to condition their pilots to “ride the shaker”, maintaining attitude and altitude during the stall, waiting for power to wrestle the airplane back up to a safe airspeed.  The practical outcome is that the aircraft remains in a stall longer than necessary, and when you’ve got relatively little altitude to play with—on takeoff or approach—that may have dire consequences.

Like one of his commenters says, if he’s not in the training department at his local airline, he ought to be.

Intuition, a little too late

In media accounts of the Colgan 3407 cockpit voice recording, there is this little snippet that is both tragic and ironic:

Seven minutes later, [Captain Marvin] Renslow complained of the ice that was forming on the plane’s windshield and wings.

“That’s the most I’ve seen … most ice I’ve seen on the leading edges in a long time,” Renslow said.

A moment later, the co-pilot, Rebecca Lynn Shaw, complained of her own inexperience.

“I’ve never seen icing conditions,” she said. “I’ve never de-iced. I’ve never seen any. I’ve never experienced any of that. I don’t want to have to experience that and make those kinds of calls. You know I’d ‘ve freaked out. I’d have like seen this much ice and thought oh my gosh we were going to crash.”

Moments later, the crew lowered the plane’s flaps and landing gear, and the plane quickly encountered trouble.

— Jerry Zremski.  ” Pilot: ‘Most icing I’ve seen’; Co-pilot: ‘I’ve never de-iced.’ “, Buffalo News, May 12th, 2009.

Maybe sometimes it’s best to go with your gut reaction.

A Cautionary Tale

While reading some of the updated news about Colgan Air 3407, I was reminded of a harrowing incident recounted on an aviation blog.  I include it here not as prognostication on what happened to Colgan 3407, but as a reminder that when flying into inclement weather, it is critical that the aircrew work together professionally and keep flight safety front of mind at all times.

runny_vortilons[The captain] has spoken to the boss, and they have decided that we will continue on and get back to our base. That means at least 1.5 hours in the ice, instead of the 30 min we have just completed. I am not happy about this, and we get into a screaming match in front of everyone. Classy. Eventually I give in and get into the plane. Though I am NOT happy about it. It is my leg to fly, but I refuse, stating that since my input was not required while making the decision to do this leg, I will not fly. I am a passenger. What else can I do, besides stay there, alone, cold, with no where to go.

We take off.

We start picking up ice.

Lots of ice.

We change altitude.

Still more ice.

We are now unable to maintain altitude.

Descend.

The captain comments that it ‘doesnt’ look as bad as the last leg’. I point out that we have an ever lower airspeed that before, and are using a higher power setting on the engines. In fact, we are at max power.

We are now drifting down towards the ground, the windshield caked in ice so bad we can barely see out. The ice on the wings extends back a foot and a half back from the boots. I feel ill imagining what the tail is looking like. We are inching closer and closer to a tail stall, I can just feel it.

— Anonymous pilot, “The Night of Ice“, Sulako’s Blog, April 8th, 2008.

Read the whole thing.  That particular aircrew is lucky to be alive.

Image “Runny Vortilons” from Fiveholer’s Flickr stream.

RELATED: Neptunus Lex presciently points to a 1998 NASA video describing the tailplane icing phenomenon.

What do you want, a hero cookie?

The pax on US Airways Flight 1549 are being upgraded to preferred status for a year, in addition to getting $5,000 for lost luggage and full reimbursement of their airfare.  Wonderful PR, and a smart move.  But not enough for some passengers, according to the WSJ and New York Post:

Some who were on the plane – brought down by a flock of geese after takeoff from La Guardia Airport on Jan. 15 – said the temporary tease of first-class perks is for the birds.

“I think if you survive a plane crash, being upgraded permanently is a good gesture too,” said Fred Berretta, 41, of Charlotte, NC, where the Airbus A320 was headed.

Manhattanite Tess Sosa, who escaped the sinking plane with her husband and two small children, thought the airline was too focused on self-congratulations – and “they want to exonerate themselves as much as they can.”

“They are happy they had such amazing results, and they applaud themselves, and then give us a small token?” she said. “That’s how I take it.”

…At La Guardia yesterday, other US Airways travelers were shocked by the airline’s lowballing.

“You’re going to crash me into the water, and you’re going to tell me all I get is an upgrade?” asked Antonio Sales, 20, who was traveling with the University of South Carolina’s track team. “That’s more of an ‘OK, you’re not dead, I’ll give you something to hold on to.’ It’s not enough at all.”

Teammate Gabrielle Glenn, 20, was more blunt: “That’s it. They should sue.”

— Ana Maria Alaya.  “Survivors Gilt: Give us more, US Aiways passengers demand“, New York Post, February 3rd, 2009.

This is what happens when you raise a few generations of kids with enormous self-esteem and absolutely no sense of responsibility.  Or perspective.

In order for the airline to owe anybody anything, they would have to be at fault.

In order for them to be at fault, they would have to have been negligent in their duty of care to the passengers.

Geese getting sucked into an engine nacelle is not negligence.  It is an accepted risk.  Your acceptance of that risk is spelled out in the terms of your ticket, if you read the fine print carefully.

There are something like 10,000 bird strikes in the US alone every year; 4,000 and change reported by the Air Force, and the remainder reported by civil aviators.

Airports and aircraft manufacturers alike do what they can to make the airport grounds less attractive, and the aircraft better at withstanding impacts.  Nonetheless, hitting a 4-pound body at 250kts or greater will do some damage to the aircraft.  Hitting a heavier bird, or multiple birds, will do a lot more damage.

Aircraft-mounted TCAS (traffic collision avoidance system) has a very limited ability to identify birds.  TCAS is mainly geared toward detecting larger, faster-moving targets, like other aircraft.  Hitting another plane can often be fatal, as you might guess.

Additionally, wild birds are horrible pilots.  They routinely fly without clearance, without Mode C transponders, and without keeping an ear tuned to the local ATC or CTAF frequency.  They change course and altitude without advisories to neighbouring traffic, and they have runway incursions every other day.

If you really want to make a difference in bird strike hazards, fund the hell out of the ABL program.  There is no bird strike hazard that an appropriate number of laser-armed 747s cannot handle.  Given the number of geese, gulls, and hell, squirrels and raccoons in this city, I’d say Toronto alone needs a fleet of about fifteen.  Being able to handle ICBMs as well is just icing on the cake.

Even the “technical” media get aviation details wrong

I’ve come to the conclusion that Popular Mechanics is a lot like the TV show Mythbusters—occasionally entertaining, but prone to screwing up its own product by operating from arbitrary supposition rather than diligent research and hard science.

Just about every time I see Adam Savage and Jamie Hyneman cooking up some crazy idea, like say a rocket-powered car taking flight, it’s plainly obvious they haven’t thought out big chunks of physics.  Stuff like the vehicle’s center of gravity, moment of inertia, control surfaces, stability during flight, et cetera.  That’s one episode where an appropriately scaled proof-of-concept would have been a good idea.  You don’t even get to see a little model car take flight; you just get to see the whole exercise end in flaming failure because of a manufacturing or installation defect in the car-to-be-flown.

Another Mythbusters goof would be the “Bullet Proof Water” episode, crafted to determine what calibre of bullet would penetrate deepest into a relatively shallow body of water.  The finding was that point-blank firing of high-speed bullets (in excess of around 1000 fps) resulted in bullet fragmentation within one or two feet of water penetration.  The implication is that the opening of Saving Private Ryan, showing GIs taking lethal rounds underwater, was a load of horseshit.  History may recall, though, that the Germans at Normandy weren’t firing into the water at point-blank range, they were firing from hardened emplacements several hundred yards away.  This would give German rounds time to fully stabilise in flight, and also, not coincidentally, to shed speed, making their entry into the water less traumatic.  Another factor is that blunt-nosed projectiles (i.e. low-velocity pistol bullets) create low pressure cavitation that reduces drag on the rest of the projectile, which is, not coincidentally, why submarines and torpedoes alike have that blunt-nosed shape.  Go figure.

Let us also not forget the “Firearms Folklore” episode, which tests the hypothesis that a sniper can kill another sniper by shooting straight through the victim’s scope.  Setting aside the fact that a Marine sniper (Carlos Hathcock) is on record as having achieved this remarkable feat, the Mythbusters did not use a period-appropriate scope (of Soviet design), nor did they use the rifle type issued to Marine snipers.  Yet they found the “myth” to be “busted”.  When they tested it again later, with a much smaller period-appropriate scope, they were able to duplicate the feat and call it plausible.  See what happens when you do better research?

At any rate, while pop-science media like Popular Mechanics and Mythbusters can occasionally be good illustrations of a principle or effect, they can also be dismal examples of poor research.  Check out this nonsense from a recent article about US Air Flight 1549:

The Right Stuff
When both engines failed, Captain Sullenberger found himself in the kind of situation that doesn’t arise even on a pilot simulator. At that point, “he found himself in the position of being an experimental test pilot,” says [Fred] George.  So Sullenberger did what all good aviators do (and what glider pilots know best): He kept flying the plane.

— Allen St. John.  “What Went Right: Flight 1549 Airbus A-320’s Ditch into the Hudson“, Popular Mechanics, January 17th, 2009.

[ed: Mr. Fred George is, according to Popular Mechanics, “a senior editor at Business and Commercial Aviation and a former Navy pilot who has clocked hours on an Airbus A-320”.]

Captain Sullenberger and First Officer Skiles are indeed sterling aviators, while Mr. Fred George is perhaps given to some hyperbole.  The captain’s dire engine-out situation is indeed envisioned and prepared for, even in the A320 simulator.  The checklist is called “Dual Engine Flame Out with Fuel Remaining“, and amazingly enough, at the Flight Level 390 blog, one can read about another A320 line pilot encountering that very checklist two years ago on a simulator checkride.  How very curious.

A checklist for dual engine flameout would also be required by the FAA as part of the aircraft’s certification to fly in the United States.  And during pre-production testing, the manufacturer’s chief test pilot would have flown that very checklist, in the simulator and in the actual aircraft (although, for safety reasons, with throttles at flight idle and not with engines shut down).

Alas, Popular Mechanics, it may be a rare checklist to encounter, but it is not exactly experimental.  Your source has led you astray.  To your credit, though, the rest of the article is a good summary of the things that the aircrew did right.

One good PM article is this one, “10 Plane Crashes That Changed Aviation“, although I quibble over the the inclusion of some of the accidents, like Swissair 111.

A far more significant accident was Pan Am 1736 and KLM 4805 at Tenerife, in 1977.  The resulting changes were worldwide—greater emphasis on English as the lingua franca of aviation, introducing standardised nomenclature and phraseology, and increased awareness of CRM as a critical factor.

Former governor-general almost lost in horrific aviation accident

From a Globe & Mail interview with the former Governor-General of Canada, Her Excellency the Right Honourable Adrienne Clarkson:

G&M: Any scary flying experiences?

AC:  I once remember flying in a plane from Ottawa and we were in a thunderstorm and we tried to land and we couldn’t and we were just a few feet from the ground when we started to go up again. I’ve been told by people who know about airplanes and about flying that this is one of the most dangerous things that can happen to you.

— Sandy Farran, “Executive class: Adrienne Clarkson“.  Globe & Mail October 17th, 2007.

No, I’m afraid it’s not.  These people you’ve talked to, who “know about airplanes and flying”, are capital-i Idiots.

Many, many things can cause a pilot to abort a landing a few feet off the deck.  Perhaps the weather conditions are below the RVR (runway visual range) minima specified for that runway.  Perhaps the runway is obstructed—by rain or snow, debris, a ground vehicle, or a previous arrival which may still be on the runway.  Perhaps the pilot has floated too far down the runway and realises there is not enough room left to stop.  In all cases, the safer course of action is to execute a missed approach and avoid whatever runway conditions the pilot deems unsafe.

Missed approaches, incidentally, are thoroughly, entirely routine.  So routine, in fact, that every runway in the country has a specific missed approach procedure published on its approach plates.  Even the ones way up in the high arctic only visited a couple times a year by Canadian Forces aircraft.  A pilot that executes a missed approach is not considered a “bad” pilot, or an inexperienced pilot.  It happens to everyone at all skill levels, often due to circumstances beyond their control—like say, weather.  I guarantee you that every pilot alive today has executed a missed approach.  Low-time student pilots are taught how to identify situations in which you may wish to abort your landing attempt; it’s not that dangerous.

CNE3_Rwy07 For example, to the left I have copied the missed approach procedure for Bearskin Lake, a small 3500-foot gravel strip in northwestern Ontario.  Click on it to see a larger image.  I have shaded the missed approach information in red.   A low-traffic gravel strip in the middle of nowhere still has a specific set of procedures to execute in case the pilot aborts the approach.  And they are printed on the approach chart the pilot will be referring to while flying down to the runway.  How about that.

More importantly, if a pilot is a dozen feet from the ground but, in the interests of flight safety, aborts the landing, the most dangerous thing that could have happened is for your pilot to continue to plunk his or her airplane down on the runway in spite of their better judgment.

As far as I’m concerned the most dangerous thing that can happen is severe structural/mechanical failure, where any decision the aircrew makes will have absolutely no effect on the fatal outcome.   Thinking of El Al Flight 1862China Airlines Flight 358 and China Airlines Flight 611 in particular.  Would you rather ride an aircraft with critically damaged control surfaces 3 miles down to the ground, or have your pilot abort the approach in a fully functional aircraft and try again?