Wednesday, May 13, 2009

Thirty Seconds of Silence

By now you've likely heard the news accounts of Colgan 3407's last minutes as captured by the Cockpit Voice Recorder (CVR). The NTSB released the CVR transcript today along with hundreds of pages of analysis, much of which is actually more informative than the CVR. Of course, the contents of the CVR transcript are easiest for the general public to grasp - and appeals most to voyeuristic impulses - so that is what was mostly reported.

Most news accounts that I saw focused on the two most sensational elements of the transcript: a statement by the First Officer regarding her inexperience in icing several minutes before the crash, and the crew's last expletives and cries in the moments before impact. Both tidbits are completely irrelevant to the investigation in and of themselves, yet do indirectly offer some clues. The First Officer's statement - that she'd never been in icing before Colgan and was glad to get a winter under her belt before upgrading - was noteworthy mainly in that it was part of a rambling, unceasing conversation that began in cruise and didn't abate until a few miles outside the marker. Put bluntly, sterile cockpit was not observed. The crew will be harshly and universally condemned for this, from the NTSB to the web boards to the lawyers. It is important to note that one cannot point to this conversation as the cause of the accident because most everything was normal while it was ongoing, and the oversight that resulted in the upset took place several minutes after the conversation had ceased. The superfluous chatter may, however, be taken as a symptom of a crew that was not 100% focused on the task at hand.

The last thirty seconds of the CVR, meanwhile, are notable for just how little gets said. Beyond the few exclamatory comments relayed by the press, there are only a few fragments and half-sentences exchanged from the time that it becomes clear that all is not well until impact: "uhhh," "I put the flaps up," "should the gear up?" and "gear up oh #!" It's an indication of how thoroughly surprised and quickly overwhelmed this crew was. There were no standard recovery procedures used, no callouts or coordination, only furious reaction. If the CVR was the only tool at the investigators' disposal, the one and only clue it would provide is a constant noise in the background through the end of the recording: the staccato chatter of a stick shaker.

The Flight Data Recorder (FDR), on the other hand, tells the grim story with an accuracy and clarity that the unfortunate crew never knew. It records in exquisite detail the status and output of every single major sensor and system on the aircraft, 121 parameters in all. The NTSB painstakingly graphed out every pertinent piece of data against various timelines, from the entire flight to the last desperate seconds. Simply thumbing quickly through the graphs gives the very distinct impression that things went south very quickly: the lines go from straight and orderly to severe and chaotic in a manner of seconds. Much closer study of the data contained within, taken alongside the CVR transcript, gives one a very good idea of just what happened on that snowy February night.

The best place to start is at 22:16:00 Eastern Standard Time, a mere 53.9 seconds before impact. Up to this point, everything is utterly normal so far as aircraft control goes. The Q400 is level at 2400 feet and 180 knots, intercepting the localizer for Runway 23 at Buffalo; the flight has been cleared for the approach. The autopilot is engaged, and the flaps are extended to five degrees (Flaps 5). The Captain is the Pilot Flying and the First Officer is the Pilot Monitoring. The aircraft has a moderate amount of ice on it, but not enough to affect performance significantly. The crew has correctly switched the "Ref Speeds" switch on the ice protection panel to "Increase," which decreases the angle of attack at which the stall protection system activates. During their preparation for the approach, the crew set a V-app speed of 118, which was correct for their weight and configuration but did not include the mandatory 20 knot icing additive. It's a small but important detail that got overlooked during their conversation.

At 22:16:00, the Captain reduced the power levers to flight idle to slow down for landing. A few seconds later he called "gear down, loc's alive" and the FO extended the landing gear and moved the condition levers to their maximum position, 1020 RPM. Both landing gear and flat-pitch propellers on the Q400 are quite draggy, and the rate of deceleration increased. In the next ten seconds, the airspeed decreased from 170 knots to 149, already a fairly slow speed for Flaps 5. At 22:16:21 the FO noted "gear's down," and the Captain immediately called "Flaps 15, before landing checklist."

Perhaps the FO noticed the low speed cue rising menacingly on the Primary Flight Display, because she paused a few seconds before moving the flap handle, only put it to 10 degrees, and began "uhhh...." One second later, the stick shaker began clattering away, almost immediately accompanied by the autopilot disconnect horn. It would continue to blare through the rest of the recording, although it could've been silenced by pushing the autopilot disconnect on the control wheel. At the moment the stick shaker activated, 22:16:27.4, the flaps were moving through 6.7 degrees and the airspeed was 126 knots.

Neither the Captain nor the FO said anything about the stick shaker. In fact, neither pilot said anything at all for a full ten seconds. The Captain did react, however, immediately and decisively. Within half a second, he hauled back on the yoke with almost 30 pounds of force. It was enough to send vertical acceleration from 1G to 1.44G. He subsequently relaxed the back force somewhat, but pitch continued to increase to a maximum of 30 degrees by 22:16:33. Meanwhile, the Captain advanced the power levers to around 70 degrees and left them there; neither he nor the FO seem to have noticed that they weren't at the rating detent, much less the mechanical limits. The Q400's engines can produce up to 130% torque in an emergency, but in this case they never went above 80%.

The Q400 is notorious for its left turning tendencies when power is advanced, and they were magnified by the aircraft's slow speed. As the aircraft pitched up, it also began banking left despite increasing right rudder. By the time the aircraft reached its apex of 2600' feet, it was in a 45 degree bank. The Captain responded with significant right control wheel deflection, which deployed the roll spoilers on the right wing.

We don't know exactly when the stick pusher fired because the FDR only samples it once every four seconds. We know it was active by 22:16:34, and that the Captain responded with renewed stick force of around 40 pounds. The airspeed was now under 100 knots; angle of attack reached 23 degrees. At 22:16:34, the aircraft simultaneously pitched down rapidly and snapped to the right, rolling straight through level and reaching 110 degrees of right bank within seconds. It was at this point that the Captain muttered "Jesus Christ," the first word he spoke since calling for Flaps 15 and the before landing checklist. At the same moment, the First Officer put the flap handle to zero without prompting, and then announced "I put the flaps up." The flaps move slowly on the Q400; they only reached Flaps 0 a few seconds before impact. Its questionable whether the situation was recoverable at this point, but retracting the flaps certainly didn't help matters.

Using full deflection left aileron and rudder, the Captain was actually able to recover from the past-vertical right bank to a shallow left bank. The pitch was bobbling near zero, and the angle of attack fluctuated between 15 and 25 degrees. The stick pusher momentarily stopped firing, and suddenly the control wheel back pressure increased to over sixty pounds. The pusher fired again, and the Captain overrode it for the last 12 seconds with 80 to 120 pounds of force. The plane snapped right past 90 degrees bank again; this time the nose dropped well below the horizon, to about -45 degrees pitch. "Should the gear up?" the FO asked; the CA responded, "gear up oh #."

The crew fought to the end, getting the bank back to around 30 degrees and the pitch to -25 degrees. The airspeed momentarily increased to 160 knots. The angle of attack, though, was still well in excess of 20 degrees and the rate of descent was around 10,000 feet per minute. The crew's last words make it clear that they knew the gig was up a few seconds before the recording ends.

It was 27 seconds from the time the stick shaker went off until impact. When the shaker went off, the airplane was still flying just fine; in fact, the angle of attack was only about 8 degrees. At this point the recovery procedure was fairly straightforward; the Captain practiced it several times quite recently in the simulator. Why he instead reacted by yanking back on the yoke is going to be the cause of a lot of speculation throughout the aviation world, but will never be truly known. Even after the pitch up and subsequent stall, recovery was not out of the question with the right stall recovery technique. Most airlines, however, do not teach stall recovery, and even if Colgan had it is impossible to say whether this crew would have recalled and executed it in time to save the airplane.

This is the easy part of an accident investigation: finding out what happened. Investigating why it happened can be much, much more difficult. This is what the NTSB is focused on now; they'll have plenty to say on the subject, and I'll have a few things to say myself. In the meantime though, this accident provides a reminder of how quickly things can turn bad in our profession. A read through Colgan 3407's CVR transcript should provide more than enough motivation to focus on the matter at hand and leave the distractions at cruise altitude.

52 comments:

VanMan said...

Thanks for that analysis, the best I've read on any media since the NTSB reports became public

AccessVegas.com said...

Sam... thanks so much for the insight.

Look... I'm a lowly FlightSim lover who has some time in a 182 with a CFI. But I'm troubled because even with the little computer game I play... I've learned something:

Sterile cockpit:

We morons who do FlightSim may watch TV or listen to music or talk on the phone "at altitude" with autopilot, but landing the damn thing even on the computer game takes concentration. On the rare times I've crashed on final (plus the numerous go-arounds), it was because I didn't "get my head in the game" until too late on final.

Final Note: I hesitated to write the above because I have no background or expertise to "Monday Morning Quarterback" the situation.

Here's why I do write this: I'm probably not the only person reading your blog who has a few CFI hours in and eventually wants to get my private ticket.

I think you stressed it best: When flying, focus on the matter at hand. Distractions in life area all too easy. Flying (even for fun in a very real airplane) has moments we need to be very, very serious about.

C-GAUN™ said...

Ahahaha Loved your comment AccessVegas

siouxpilot said...

Sam, my first thoughts when I heard about this accident was tailplane stall. The recovery for a tailplane stall is to pull on the yoke, not push like a normal stall. When I heard thats what he did it confirmed it more. Now that I'm hearing more I don't know. Do you think that the captain just assumed, because of the icing, that it was a tailplane stall and used the wrong recovery procedure?

Also thanks for reading my blog, it's always nice to meet former instructors from UND.

Sarah said...

Thanks for the cogent analysis of the time-line, Sam. We'll never know what the crew was thinking in those 30 seconds, only what they said, did and the parameters of flight.

The lesson to take away is unclear to me, a non-professional pilot. Sterile cockpit? Over use of the autopilot? Fatigue & crew health? Spotty training? Mistaken unspoken diagnosis of the problem as tail stall? All issues played a role, but in the end there were just too many to recover from.

May they all rest in peace but wake up the rest of us.

Ron Amundson said...

I reviewed the FDR charts this morning. Not being familiar with the Q400, the pitch trim changes as well as the ice detect plus the uhhh on the CVR raise an eyebrow or two. As you state the A/S was low for the configuration, so perhaps that was the rationale... but being tail plan stalls were likely on their mind, the combination and sequence of FDR events is troubling.

I'm always leery to attribute things to Pilot error, as almost always there are hidden demons lurking waiting to get the next guy. Yet, I must admit some bias too, as a youngster I know trained with the FO, and it seems very hard to believe the FO would be behind the A/C, despite the sleep, training, and sterile cockpit issues. Otoh, every pilot out there has had a series of events stack against them at one time or another.

Kate said...

Thanks for such a clear and concise description of the events. Lots to think about in this one, and I hope we all can learn something from it... (I remember discussing accidents like Air Florida in Siewert's Aviation Safety class, and something like this would be much more relevant to talk about at that point in a young pilot's career.)
Anyhow, I have to agree with "VanMan" - good job with the post.
-Kate (UND 2000, found your blog thru Cockpit Conversation, I believe.)

Sam said...

sioux - I initially thought tailplane stall, but realized that the Q400 doesn't really fit the profile. It has a hydraulic elevator rather than aerodynamic tabs, and the tail is tall enough and far enough back to be out of the wings' downwash. The Captain *thinking* it was a tailplane stall and reacting accordingly is a possibility; for that matter, that could be what the FO was thinking when she retracted the flaps.

We do know the Captain had just come from the SF340, which is susceptible to tailplane stall, and had just watched a tailplane stall video in recurrent training. Whether it was actually on his mind is impossible to say. Of course, a stick shaker is the strongest clue of an impending wing, not tailplane, stall. The event he reacted so strongly to to was not an abrupt pitch down, but a stick shaker. Its possible that he later mistook the pusher for a tailplane stall, forgetting that with a hydraulic elevator you'd never feel the tailplane stall in the control column. It's a possibility, but to my mind no greater than the possibility that he was simply recovering from a stick shaker the same way it's stupidly taught in a sim - maintain altitude! - and overreacted in his surprise.

Sarah - a very fitting epitaph, indeed.

Ron - reading the human performance group interviews, one gets the impression that both pilots were well liked and respected. The NTSB couldn't find anyone willing to speak ill of the dead's flying skills, busted checkrides notwithstanding. I agree that while we all try to find the lessons to glean from this, it's important to not pass judgement on the pilots too hastily because we simply weren't there and have no idea how we would react in that situation.

Kate- welcome to the blog, I'm UND '02. I think that training for aspiring career pilots in general needs to place greater emphasis on professionalism and the need to approach each flight with a dead serious attitude. This is the latest in a string of regional airline accidents where the crew exhibited a rather cavalier attitude toward operating the airplane. I'll have more to say about this in a future post.

Capt. Wilko said...

Good analysis, Sam.
Yes, sterile cockpit was broken but that is unlikely to have alone contributed to this accident. It is, unfortunately, broken all-too-often and rarely leads to an accident.
I heard through some channels that the FO was a commuter from the West Coast and had considered fatiguing or calling in sick, but didn't. While the FARs are very clear about the pilot's responsibility in this respect, you know as well as I do that the decision isn't always that clear-cut because of how individual companies deal with these matters.
I haven't looked at the NTSB report yet, but I hope they consider fatigue seriously in this crash. It is often brushed off as a mere contributing factor but is a much bigger problem than the board makes it to be.
Problem is I doubt the airlines would welcome more stringent rest rules...

Tim said...

The NTSB site has been hammered ever since the report came out. Any chance you can put the PDF of the report (which you must have due to your excellent analysis) up somewhere where I can pull it from? Would love to read in more detail.

Sam said...

You know, I haven't had a ton of problems with the NTSB site. Sometimes the connection will get interrupted, but I can usually pull the docs on the 2nd or 3rd try. Here are the relevant links from the public docket:

Flight Data Recorder contentsCockpit Voice Recorder contentsAircraft Performance Group report (FDR analysis)Operations Group reportHuman Performance Group reportThere are a ton of supporting documents available here.

Sam said...

Ack forgot those pesky < br > tags...

Jerel said...

Sam, as I watched the NTSB video on 'YouTube' over and over, I kept wondering one critical thing. The speed of the aircraft. After the stall, I'm compelled to believe that had the captain just gotten his speed back above 135 knots or more he would of been able to get his plane flying again. Despite his various bank angles, and trying so hard to get his wings level, his speed constantly remained so slow (around 95-105 knots or so) that the aircraft just couldn't keep flying. Like watching a horror movie, I'm screaming "Lower the nose!", "Lower the nose!". He might of overstressed the flaps, but I think he would of been able to recover, reconfigure the plane, and live to fly another day. So now I wonder if there was something that kept the captain from doing just that? I know hind-sight is 20/20. It's just so sad what happened to all on board. As you say, we'll never truly know what the crew was thinking and experiencing during that event; just that it wasn't good. (UND Class of '96)

Anonymous said...

Great Post. Your objectivity is refreshing. This crew has been reamed in other blogs and boards all accross the net. Although I am sure some of it may be justified, I am not really in a position to make that determination.

I am not in your business, but I am in a businees where disasters occur and people lose their lives or become injured. Disasters are usually not a single large event, but a chain of smaller events that lead to a catastrophic result. The objectivie is to remove as many of the links in the chain to prevent the occurance.

Having said all of that, a few items come to mind after reading the entire transcript last night.

First was the dynamic between the Capt. and the F/O. It did not appear to be an instructor / student dynamic or a peer / team member dynamic but rather as sort as if the F/O did not have confidence in her abilities and the Capt. compensated for it through wit and casual conversation. The dynamic just seemed odd to me.

Second, I would have thought the F/O would have known what a chip detector light/warning was, even if the Q400 isn't equipped with them.

The above items as well as the physiology / fatigue issues I am sure will lead to scrutiny in the industry. Good luck and thanks for the blog.
Bob M.

Brent F. said...

Sam, thanks for the great post and analysis, as always. Good to hear a perspective from someone with time in that type.

I do have a question about the "Most airlines, however, do not teach stall recovery, and even if Colgan had it is impossible to say whether this crew would have recalled and executed it in time to save the airplane" bit.

Is stall recovery drastically different in bigger planes than in little ones? I would think that, after having that been ingrained into me since my private cert, that it would be second nature to ATP's? Or is there some part I'm missing?

David said...

1)If the tailplane had indeed been iced up, as it appears the flight crew seemed to believe, couldn't it have stalled even though it's tall enough & far enough back to be out of the wing downwash?

2)Do commuter airliners--and this one in particular--usually have angle of attack gauges?

jetdrvr said...

I'm retired from heavies and have no time in medium turboprops. I flew the Herc for 8 years, but that's no T tail.

My question is why did he continue to pull back against a stick shaker, fail to apply max power and regain flying speed? It makes no sense to fight the stall warning device. Stall recovery is pretty much the same for every aircraft, yet this guy was pulling up-elevator while fighting an incipient stall/spin. Airspeed, airspeed, airspeed! Why did the FO retract the flaps in the middle of a stall situation unilaterally? I'll never understand it. It makes no sense. RIP.

Thanks for the good post.

Kevin said...

Nice technical summation.

I don't read it as a violation of sterile cockpit, I see the FO beating around the bush about the ice.

She made a very passive, indirect approach at the issue (the old UA Assertive CRM Statement stuff from 1978).

She was obviously trying to say "Yo buddy, this shiites scary have we done everything we're supposed to? i.e. set Vref correctly, maintain enough power for the boots, have all the switches switched right.

For whatever reasons he didn't pick up on her reverse assertive statement.

Perhaps, had she done the boring old assertive statement taught to every freaking new hire and recurrent slob for the last 31 years we wouldn't know the poor guy couldn't fly out of a stall. Who said paper bag? Not me.

He would have set the bug to 138 and if the company culture is fly Vref he probably could have flown it. Stick shaker went off at what 131?

I'm old and frequently mess up all those switches, knobs and bugs. I need an FO to keep my stuff right.

Paul said...

I reckon they had no idea what really happened. Their stall training had only involved their deliberate entry and recovery by their own hands. Here they were confronted with a cacophony from autopilot disconnect and stall warning, and that memory of "don't lose altitude." This was compounded by the nose-up trim left by the autopilot, and the added inclination of the nose to rise with application of power on wing-mounted engines. No doubt, there were errors that led to the event, but with practical training they might have recognized their situation and, perhaps, recovered.

Eric said...

The one thing that bugged me most watching the video is that they leveled off (on autopilot the whole time) without taking the throttles out of idle.

I teach my students (in complex aircraft) to keep the throttle(s) at the bottom of the green during descents, as that way they have enough power to remain level, even if the AP takes them out of the descent while their attention is elsewhere. The captain of the Q400 had idle throttles, 5 (going to 15) flaps, and gear down... is that a typical situation for the aircraft, Sam?

VanMan said...

The Buffalo News has good coverage including all of the NTSB reports.
http://www.buffalonews.com/532

Sam said...

Jerel, it wasn't simply speed, the AoA was seriously high, up to 30 degrees at times. I don't know whether recovering a Q400 that's so deeply stalled in 1500 feet is possible...transport category aircraft aren't required to demonstrate it in flight testing, since the assumption is that a stick pusher will keep them *out* of a stall. That said, I'd imagine recovering a Q400 from a deep stall would be a lot easier than most swept-wing jets. You're certainly not going to recover by holding in 80-120 lbs of nose up stick force, though....

Anonymous 10:58 - I noticed that too. It sounded like a mentor/protoge dynamic, she was playing the newbie and he was playing the crusty old salt regaling her with stories from the good old days. Now, that's not unusual in the regionals: we have a lot of newbies, and a lot of CAs who consider themselves crusty old salts after a few years in the left seat. The funny thing here was that he didn't have that many more hours than she did, she had previously had a real job as a CFI while he paid to sit in the right seat of a 1900 (Gulfstream), and she had 700 hrs in the Q400 vs his 100!

I don't suppose one would know what a chip detector is unless one had taken an in depth systems course, had flown an aircraft with one, or had previously heard a story involving a chip detector. Most modern aircraft that have them don't have the chip detector light, they have a "Eng 2 No Dispatch" EICAS message, and furthermore nowhere in the QRH, MEL, or AOM will it tell you what that message really means other than you can't take off again!

Sam said...

Brent F - you unstall an airliner just like you unstall a 172, by reducing angle of attack. Unfortunately the airlines operate under the assumption that their airplanes will never actually stall, because the stick shaker will alert the pilots to the dangerous slow speed situation first, and if that doesn't work the stick pusher will kick in. Therefore, the airline's "stall training" is actually misnamed, it's really "stick shaker recovery training." The idea is that you simply go full power, don't gain or lose altitude, and reconfigure as you gain airspeed. The not losing altitude thing comes straight from the FAA's PTS. The problem is that many aircraft actually require back elevator pressure to not lose altitude during this maneuver, so you actually "ride" the stick shaker longer when simply releasing all pressure on the yoke would've stopped the stick shaker immediately (lower the AoA) and resulted in very acceptable altitude loss of two or three hundred feet. The other problem is that the entire maneuver is done with the autopilot off and you stop trimming well before the stick shaker.

There are therefore three problems with airline "stall training":

1. You train to recover from a stick shaker in very different circumstances from those in which most stick shaker events take place (autopilot on, distracted).

2. Your training introduces motor memory that, amplified by adrenaline, can bring you closer to a stall.

3. The stick shaker recovery procedure is useless for stall recovery and can lead a panicked pilot to do counterproductive things like trying not to lose altitude, raising the gear & flaps, etc.

I recently got to experience how one regional airline does things completely differently. Right now they're the only one in the industry that does practical stall training, but I don't think they'll be the only one for long. Look for a post about this very soon.

Sam said...

David, the airplanes that are most susceptible to tail stalls are those with unpowered or aerodynamically powered elevators, fixed (untrimable) horizontal stabilizers, and tails that are close enough to the wings wake to be affected by increased downflow when flaps are extended. The Q400 does have a fixed horizontal stab, but the tail is 15 feet above and 40 feet behind the wing, and the elevators are hydraulically powered. It doesn't fit the profile.

2) The JungleBus has an indirect indication of AoA in that we have a flight path indicator on the PFD. The Q400 has no indication of AoA.

Sam said...

Kevin, her one statement that might've been meant to come across as "this ice scares me, do something" was part of a larger conversation that really didn't stop at all when they went below 10k. You can make the argument that her statement indirectly pertained to safety of flight, but most of the rest you cannot.

Paul - I agree. Is this Paul K? I'll be posting the writeup of our time in the sim soon.

Eric - Umm, they were already level at 2400 feet. They initially had around 35% torque to stay level at 180 kts with flaps 0 and then 5; the Captain subsequently went to flight idle to slow for the approach. The flying really was 100% standard for that aircraft right up to the point that he called for Flaps 15 late, and then neglected to bring the power levers up to arrest the decay in airspeed.

Anonymous said...

Just curious. Besides the drag from the landing gear, why did the airspeed decrease so dramatically?
From what I can see it went from 170 to 130 in about 10 seconds.
Seems any pilot would have had a heard time dealing with that.

D. Patrick Caldwell said...

You know Sam, I think one problem is that most pilots think that the stick changes altitude. The fact is that the stick isn't an altitude control, it's a pitch control.

I mean, 120 lbs of force is a lot of effort to deepen a stall, you know? It strikes me that this pilot believed that he was supposed to pull back on the stick to get more altitude but that's just not the case.

Also, he seemed to have a poor understanding of the aerodynamics of the stall. When you're that close to a stall, full aileron deflection is good way to stall the wingtips and start spinning.

Do you agree?

Kevin said...

Sam -

Point taken about the non stop nonessential chatter for the entire descent. I may be jaded. I've logged quite a few thousand hours (seems like it) with a person whose need to speak incessantly increases with her level of agitation. Perhaps I could point out the TV in the living room is well below 10,000 ft. and therefore it's a "sterile" environment. Sorry to digress.

Did anyone pick up on the Check Airmen and sim instructor interviews regarding the stall training?

Seems the Training Department may not have kept up with the regulation. At least the Sim Instructor talked about training the CA to his "Personal Standard" of 100 ft altitude loss. I cringed when I read that.

Wasn't it changed to "minimum altitude loss appropriate to the aircraft" to specifically address this type of event?

Seems I recall a few years back reviewing "Startle Factor" and then exchanging altitude for energy. Was this just high altitude (turbojet) upset recovery?

Rosenker seems to be a very impressive Chair during these proceedings. That being said, when I participated in inspections by FAA, DOT, at our training department I never would have shown up with out a FCOM, QRH, GOM, Training Manual, FAR's and 8400.10. It appears most of the interview subjects tend to just rely on memory while on the "hot seat".

Does the NTSB not allow the use of reference material for the interview subjects? Seems like the company employees would have had a much better showing had they referred to the current approved manuals rather than winging it.

Mike said...

what really stinks is that all the preventive measures implemented in the AP to prevent such a crash actually didn't do squat.

Stick shaker=>pull up
Stick pusher=>pull up even more

I wonder how the outcome would have been if the approach had been flown by hand...I'd love to speculate but I only know enough on the subject to say I don't know enough :)

Anonymous said...

here's an article that was in canada's national paper today:

http://www.theglobeandmail.com/servlet/story/LAC.20090514.CRASH14ART2240/TPStory/TPInternational/America/

Anonymous said...

Life in the cockpit 'a recipe for an accident'
A hearing into a deadly crash near Buffalo, N.Y., casts a light on the threat posed by poorly paid, and often tired, junior pilots

JOSH WINGROVE

With a report from The Associated Press

May 14, 2009

An up-and-coming pilot with a commuter airline, Rebecca Shaw was paying her dues.

The 24-year-old old lived with her parents near Seattle, Wash., and worked at a coffee shop there on her days off. When the time came for her to fly, she commuted to work at Virginia-based Colgan Air.

As a copilot, she was paid $21 an hour, but only for flying time - not for layovers, typically in the New York area, or her cross-continent commute. She grossed $16,254 in her first year of work.

"I had gone back to visit with her, and she actually shared what she was making. 'Well, it's ... $1,000 a month, Mom,' " said her mother Lynn Morris, in an interview with a Washington news station yesterday. She had visited her daughter during a layover.
Print Edition - Section Front

Section A Front Enlarge Image
More World Stories

* Recession fuels China's Expo worries
* Pope expresses 'solidarity' with Palestinians
* Life in the cockpit 'a recipe for an accident'
* Cash-poor French pawning their grand crus
* In about-face, Obama seeks to keep abuse photos secret
* IN BRIEF Pirates co-ordinating attacks, naval leader says
* Go to the World section

The Globe and Mail

"And I go, 'Well, how can you [afford] a crash pad in New York?' And to answer that question, she had done her thinking. Her plan was to get a hotel room when she needed to get one."

She could rarely afford one. To make ends meet, Ms. Shaw took naps in a staff lounge the company kept at Newark Liberty International Airport in New Jersey. She often joked that a couch in the room had her name on it, though the company insists it doesn't allow sleeping in the room.

Last February, Ms. Shaw reported for work once again. She flew red-eye from Seattle to New Jersey, stopping in Memphis, Tenn. She was tired and complaining of a cold when she boarded as the copilot of Continental Connection Flight 3407 operated by Colgan Air on Feb. 12. Hours later, the plane crashed into a Buffalo-area home, killing 50 people, including everyone aboard.

Yesterday, during the second of three days of hearings into the causes of the crash, National Transportation Safety Board officials explored the fatigue of pilot Marvin Renslow and his copilot, Ms. Shaw. They painted a worrying picture of the working conditions of pilots who commute cross-country and work around the clock for minimal pay.

"When you put together the commuting patterns, the pay levels, the fact that the crew rooms aren't supposed to be used [for sleeping] but are being used - I think it's a recipe for an accident, and that's what we have here," NTSB member Kitty Higgins said.

"People can't go live in these major cities, or even in the suburbs of these major cities, at $16,000 to $17,000 a year," added Paul Rice, vice-president of the Air Line Pilots Association.

Ms. Morris agreed the conditions were less than ideal, but said her daughter did the job to accumulate flight hours and work her way up to a coveted and highly-paid job as a national airline captain.

"My original thought is it's a wonderful opportunity to progress your career," Ms. Morris said yesterday.

Ms. Morris said the hearings, which have questioned the conduct of her daughter and Mr. Renslow, are making "scapegoats" of the pair. Mr. Renslow commuted from his home in Florida to work. There were suggestions he hadn't slept before the night of Flight 3407, the worst air crash in the United States in seven years.

Mary Finnegan, Colgan's vice-president of administration, said the company permits pilots to live anywhere in the country. NTSB investigators said 93 of the 137 Colgan pilots who worked out of Newark at the time of the accident were commuting from far away.

"It is their responsibility to commute in and be fit for duty," Ms. Finnegan said.

Daniel Morgan, Colgan's vice-president for flight safety, said the airline industry has a long history of flight crews commuting long distances to report for work.

"It's not an ideal way to work, but neither is working overnight in the post office."

Among those attending the hearings was Captain Barry Wiszniowski of the Air Canada Pilots Association. He said Canadian pilots don't typically commute as far as American ones, but added that everyone can learn from the case.

"The lessons from this tragic event, from Colgan Air Flight 3407, they are lessons the entire aviation industry can learn from," Mr. Wiszniowski said yesterday.

One Canadian industry veteran said small airlines pay their young pilots very little because they know the pilots need experience.

"They know they can afford to treat the people like crap, because if the people quit there are people standing in line to take their job," said the source. "I feel sorry for her, and her parents. She couldn't afford to come a day early, stay somewhere and do the trip well-rested."

Anonymous said...

Well written and thought out Sam. I'll admit I'm a private pilot in Houston with no commercial experience like most of you, but I can't help but notice a few important items that come with experience, military training, and 39 years of observing humans:

1. Pilot: Stall recovery is like learning to ride a bicycle. Either an outside variable yet undiscovered is to blame, the captain lost his marbles, or he deliberately yanked back thinking he was in a tailplane stall?

2. FAA/Airline: Stall recovery not mandatory in sim? Good grief. I still pracice it myself in me humble 172 and it is required for a VFR private!

3. Crew/airline: No dialogue or discussion of emergency procedures between pilot & copilot smacks of lack of THOROUGH emergency training.

4. Macro systemic: There is a reason the military insists on aerobatic, aggressive, and unusual attitude FLIGHT (not sim). You cannot prepare for the elements of surprise, fear, and performance under pressure without practice in an environment which stretches your comfort zone. I remember 10 years ago thinking that ALL pilots need a 2 week boot camp on aggressive flying techniques, unusual attitudes and basic aerobatic emergency practice in real flying conditions. Sims are great and amazing. This crew lost their minds and did not perform their training, we guess in hindsight. If that is the case, we need to acknowledge this tendency and not dismiss it - it can happen to anyone who has not dealt with a potentially catastrophic emergency in highly stressful situations with little time to react.

6. FAA/airline/industry: Fatigue, pressure to pass people on check rides, and unwillingness to fail or remove marginal pilots cannot be dismissed. The military has not problem flunking and removing questionable performance.

7. Ultimatey, the crew deserve the benefit of doubt. We will never know exactly what happened. And sometimes, s*&* just happens.

Josh Martin said...

Good writeup.

Florida Fred said...

Hi Sam:

So, I don't like how the pilots are getting all of the blame for this crash and feel that I need to get this off of my chest. I flew in to Buffalo that same night about three hours prior to Colgan 3407's arrival. We were in a B737-200 and coming in from Pittsburg. There was light to occasional moderate rhime ice between 5500 and 2500 feet. (Nothing that bad.) We were being vectored in from the South for the ILS 23 approach (sound familiar?). I was the FO for this leg and the ATIS had reported under the Notices to Airmen that "runway 23 glide slope information not available to the right of the approach course". So, I informed the pilot flying of the NOTAM as part of the approach brief.

We were given a final vector and cleared for the ILS RWY 23 approach just outside the approach gate (7-10 miles) just like Colgan 3407 was. I am not sure if you know this, but the autopilot system is very old in the 737-200 and we are always used to it failing during a coupled approach. So, like clockwork, we were monitoring the flight controls closely. We were IMC and I happened to notice that the aircraft started a very gradual descent before we captured the Localizer. I mentioned to the PF that we were not aligned with the runway and that we were descending. With that, he said that he was going to hand fly the approach. Then, I noticed that we were momentarily above glide path, and then we went well below glide path within seconds. The PF noticed it too and said, "Hey, make sure we have the right frequency dialed in..." We both confirmed the frequency and before we knew it we had shot through the localizer. ATC called and asked if anything was wrong and I said that I thought we were having a problem with our autopilot.

ATC's response was... "No, it's the glide slope; we have been having problems out there since they put in this temporary damn near the approach end of 23..." "No problem, guys, I will just vector you in from the other side." So, we got vectors back in from the North side of the field and the landing was uneventful.

I can't help but to wonder if Colgan was coupled up like we were on the right side of the localizer and they got the same indications as us... If that was the case, then that would explain why the aircraft chased after the glide slope in the up direction. As you mentioned before, the Q400 does not have auto throttles, so the PF would have to be really on top of things in order to mash the thrust levers forward. I was reading the CVR transcripts too and it happened at the same place that it happened to us. I also noticed that the FO did not brief the CA of the NOTAM in the ATIS. I wonder if when she got ATIS information Romeo, if that NOTAM was still being broadcast. I think that the NOTAM should read "glide slope information erroneous to the right of localizer". If you look in the AIM 5-4-3 it talks about False Glide slopes. I believe that is what we experienced that night. I placed a phone call to the NTSB, but no one has since called me back. I, like you, will let the investigation play out, but I truly hate how no one has mentioned a faulty ILS system.

Just for grins, and to cover my arse, I doubled checked my paper Notams (Local and FDC) and there was no mention of the glide slope having a problem before we launched to Buffalo. I don't believe that the crew should bear 100% of the blame, but like you said, I think that "sterile cockpit" techniques would have had them talking less and watching the instruments more. Either way, it's a shame to lose fellow pilots.


PS: I heard that the pilots at Southwest have an internal NOTAM system where they mentioned the False Glide slope problem at KBUF. Not sure if that is true or not.

Sam said...

Florida Fred - that's very interesting stuff; it's true that SWA put out a memo regarding false glideslopes at BUF right after the crash. However, the FDR shows that the airplane was completely level until *after* the stick shaker activated & the autopilot disconnected.

The crew screwed up badly, that much is clear. That doesn't mean the blame is 100% theirs and everyone else is innocent. There are a lot of other issues here that the NTSB has been talking about the last three days.

Sam said...

Mike - I don't doubt that handflying would have alerted the pilot to the decaying speed in this case. However, mandating that all approaches be handflown would result in an overall decrease in safety, in my opinion.

Anonymous 11:40 - I saw that article in the Globe & Mail, very excellent.

Kevin - Yes, the problem is that most companies/check airmen seem to be interpreting the "minimum altitude loss appropriate to the aircraft" as meaning the pilots should try to do the maneuver with the absolute minimum loss of altitude rather than actually explicitly saying "Trade up to 300 feet of altitude for airspeed, that is appropriate in this aircraft." I didn't see that one interview with the check airman but it's not at all out of line with how stalls are being presently taught at the airlines.

Anonymous 6:46 - The Q400's big props produce a tremendous amount of drag at flight idle and 1020RPM. At Horizon we had a "Reduced NP" button that let us keep the props at 850RPM for landing and would advance the props to 1020 in case of goaround. Colgan did not order this option. In any case, 170 to 126 in about 10 seconds of gear down and props 1020 sounds about right. Normally not a problem if you're paying attention.

D Patrick - I don't think the pilot literally thought "pull back for altitude." I don't think he was "thinking" at all at a certain point, just reacting with instinct...some part of which was perhaps prompting him "pull back to go up."

Sean said...

Sam,

What type of audible warnings, alerts, or annunciators are present on the Dash 8 (other than stick shaker) to indicate a wing stall?

Sam said...

Nothing audible, if the stick shaker doesn't get your attention nothing will. It's pretty loud and you can feel it even if your hands aren't on the yoke at the time.

Prior to the shaker, your best clue of what's coming is that the red portion of the airspeed tape (the low speed cue) is rising. I suspect that's what the FO saw when she paused before dropping the flaps and said "uhhh...."

Reed said...

This is a really great post! I am one of those guys with too much "jet time" in flight simulator to count. One of those guys that all real pilots love. Lucky for you guys, I hope to join your ranks in a few years. I've even built myself a nice home cockpit with a yoke, rudder pedals, projector, and other odds and ends. At the risk of doing the classic Monday morning quarterback/ flight sim pilot, I would love to ask about something that I haven't really seen touched on yet. What was the trim situation like? When the speed gets low, the AP will put in trim and I am curious to know how much this affected the initial pitch up. I would also like to question whether the declining airspeed was overlooked due to the fact that the pilots had their heads turned back examining the ice on the leading edges. We will never know if this was a factor or not but it is an interesting point to raise. They obviously lowered the flaps and seemed to have caught a bit of airspeed decay, but maybe they were so focused on icing that they missed the big picture. This is only speculation. I am very interested to read the NTSB report and hope I didn't offend anyone with my inquiries. The one thing I feel we can all agree on though is the sadness of the rampant pilot slandering going on in the media. Seeing Marvin and Sarah's picture on the front of the NY Post with the caption "Flight to Doom" just makes me sick.

Sam said...

Reed--

Some very astute questions there from a FS pilot... I didn't really mention trim in my post and that was kinda an oversight because it certainly played a part in how the pitch got to 30 degrees. The autopilot was continuously trimming until the stick shaker activated. This ensured a pitch-up moment when the power was advanced. The power was brought up around two seconds *after* the CA used 25-30 lbs of nose-up stick force, however, so the trim up only exacerbated an already deteriorating situation. I'll have something to say about this in the new post I'm writing now.

As to what distracted them from flying the airplane in the five or ten seconds before the shaker, we'll likely never know. Looking at the ice on the wingtips is one possibility, at QX it was standard procedure to look at the wings once more before approach to make the final determination of what position the REF SPEEDS switch should be in (and which bug speed to use, we set both Vref and Vref(ice)). Ultimately, *what* distracted them at a critical moment isn't nearly as important as *why* they were prone to distraction (fatigue & being rushed due to their chatting during descent are two possible culprits) and why the CA & FO did what they did after the shaker.

It was quite inevitable that the pilots were going to get raked over the coals in the media. There are plenty of other pilots who have joined in...I think the implication is that if you can simply peg these two as bad pilots who screwed up horribly, it's easier to say "I never would have done that." I dislike that stance very much. I fully recognize that this crew screwed the pooch, but they paid for it with their lives, I see no reason to heap further scorn on them. I wasn't there and have never been in an inadvertent surprise stick shaker situation, so I can't say with absolute certainty what I would have done. I think that unless pilots recognize that under certain circumstances it could have been any of us, and that there are some systemic issues here that are far bigger than the two pilots involved, we are collaborating with management in their efforts to sweep this one under the rug and go back to business as usual.

Standby for a few posts that'll say pretty much the same thing but with less conciseness! [grin]

Anonymous said...

Even if they were bad pilots (and I'm definitely not saying that they are), well, so what? It's the airline's job to make sure that bad pilots are not flying their planes, to determine which pilots are good and which are bad, and to either train the bad ones until they're good or fire them if they're hopeless. And it's their responsibility to pay enough that they can attract employees who can do the job well, and who can afford to sleep somewhere other than the crew lounge.

Sam said...

Anonymous, that's precisely what I meant by saying there are systemic issues much bigger than the two pilots involved. Those are all things that the majors have done pretty well at, and where the regionals leave a whole lot to be desired. This doesn't simply stop at the regionals, though. You can lay a lot of blame on the doorstep of the majors that outsource on the basis of cost alone, the unions that let them do it, and ultimately the traveling public that demands ever cheaper air transportation.

But I'm getting ahead of myself...

Anonymous said...

Hello Sam and others and thank you for some interesting and accurate analysis. I agree with reasonable certainty and informed opinion that the Q400 IS NOT suseptible to a tail plane stall, but unfortunately given the data, and in light of his previous experience, it is evident that the captain employed its recovery technique. The activiation of the stick shaker was a clear indication of the classic wing stall and proper stall recovery would have prevented this accident.

This accident is clearly pilot error, that much is certain, however, under scrutiny should also come Colgan's training program and their pay and benefits and the conditions they create for pilots. It is unlikely that deep stalls be mandated in airline training since the stress is to recover from them at first indication, but it is likely that the NTSB will make recommendations for more meaningful stall recovery training including AP on to stick shaker, low level on approach and even during go arounds.

C-GAUN™ said...

In another news, a ColganAir Bombardier Dash Q400 lost wheels of one of its landing gear right upon impact with the runway on May 12 2009. It was captured live on video by a passenger. Visit the video at http://bit.ly/xtcx0

Anonymous said...

Hi Sam, why do you say that hydraulic elevators make tailplane stall unlikely?

Anonymous said...

I'm not a pilot and have flown a Cessna 172 for 2 minutes under supervision. Much of this discussion is over my head.

What I want to talk about is minimum wage employees commuting across to country to work (!??). Then it's the minimum wage employee's responsibility to get a good night's sleep by renting a room in a city they have no chance of affording? Give me a break!

I find it very difficult to believe that Colgan management didn't know this was a problem.

While we're at it, why not supply sleeping "cubes" like I've seen at airports recently? Isn't that the least you can do for pilots earning "burger" wages?

Sam said...

Anonymous 9:13 - when airflow detaches from the underside of an unpowered elevator, or especially one which is moved aerodynamically via control tabs, the elevator can be snatched to the full nose down position, and pulling up, which is essential to unstalling the tail, can be very physically difficult, requiring well over 100 lbs of force in some aircraft. A hydraulic elevator both resists being moved aerodynamically after airflow separation, and can be unstalled with very minimal effort on the pilot's part.

The Q400 is also considered not susceptible to tail stall because the horizontal stabilizer is well out of the wing's downwash, which on conventionally-tailed airplanes can increase the tailplane angle of attack at high wing AoA or flap extension.

bud,usmc said...

neither one of these people would ever qualify as a navy/marine corps carrier pilot.

aviatorpr said...

so if they were ex navy/marine this would have never happened, yeah right....what a irresponsible comment.

Sam said...

Bud--

That statement is a short step away from "this could never happen to me," which is a giant leap towards it happening to you. NewCo's DO sent out an email this week reassuring crewmembers that "NewCo is nothing like Colgan" which, besides being untrue because we're much like Colgan in a number of ways, is something that I felt was horribly irresponsible for a DO to say.

I completely agree that the military's selection and weeding out process is much better than that of the regional airlines, and military training is generally very good. This hasn't stopped a couple of bad eggs slipping through, sometimes for long careers before they balled up an airplane. The military has had some crashes just as senseless as this one.

katie graczuk said...

Sam-

This was a great post! Although I don't have any aviation experience and know very little about planes it was very readable and I understood some (not all!) well. Do you have any opinions on, dare I say it, blame? I'm writing a feature about the crash and am interested in what the public thinks should be done (i.e additional stall training) to avoid these problems in the future and what they think of the evidence that has been presented from the investigation. Thanks so much in advance,Katie

Sam said...

Katie - if you're talking Probable Cause, we have some pretty good ideas but I'll leave the final determination to the professionals at the NTSB. If you're talking blame in a legal sense, I'll think that'll get covered pretty thoroughly by various lawyers, judges, and juries. If we're talking about blame in a moral sense, that's something I have a few opinions about, and goes a ways beyond two dead pilots. Look for my next post.