It is amazing how quickly and unexpectedly this can happen. The average time lapse between application of take-off thrust and the nose wheel leaving the runway is about 35 seconds. A few seconds after that... Disaster struck this aircraft.
Another thing that is amazing is the inaccuracy of eye witness accounts. There were numerous witnesses who claimed to have seen the number one engine on fire while the aircraft was taking off. Not true. Witnesses reported seeing the number one engine explode as the nose wheel lifts. Also, confirmed as not true after an airport video was reviewed by investigators.
This is eerily similar to another crash that happened in Detroit twenty-one years ago involving the same model of aircraft. One of our own captains lost his wife (flight attendant) in that crash.
So, now we wait for the final accident report. It is a huge tragedy... For a little review of how big, consider this morbid rule of thumb (which they used to teach in ground school years ago, before it was deemed too insensitive): Each of the 154 fatalities directly affects 10 people (1,540), but also indirectly affects 100 people (15,400). That is the reason I do not whine about how much the CEO makes while I am in the cockpit. Bad things happen quickly and when it involves a large volume of Jet-A kerosene, you had better already be thinking is the #2 engine going to fail in 10 seconds, not how much is the CEO's latest stock option worth.
Life on the Line continues...
Another thing that is amazing is the inaccuracy of eye witness accounts. There were numerous witnesses who claimed to have seen the number one engine on fire while the aircraft was taking off. Not true. Witnesses reported seeing the number one engine explode as the nose wheel lifts. Also, confirmed as not true after an airport video was reviewed by investigators.
This is eerily similar to another crash that happened in Detroit twenty-one years ago involving the same model of aircraft. One of our own captains lost his wife (flight attendant) in that crash.
So, now we wait for the final accident report. It is a huge tragedy... For a little review of how big, consider this morbid rule of thumb (which they used to teach in ground school years ago, before it was deemed too insensitive): Each of the 154 fatalities directly affects 10 people (1,540), but also indirectly affects 100 people (15,400). That is the reason I do not whine about how much the CEO makes while I am in the cockpit. Bad things happen quickly and when it involves a large volume of Jet-A kerosene, you had better already be thinking is the #2 engine going to fail in 10 seconds, not how much is the CEO's latest stock option worth.
24 comments:
Dave, I always wondered what kind of conversations they have with pilots in training. Crashes are a rare but unfortunate mathematical certainty, just like they are in my business of finance. I saw in a previous post that these things happen in three's, looks like there was a small one that went down out west and a commercial flight in Russia today. Very sad.
Hi Dave,
Well said - As a regular reader of your posts and someone who sells travel for a living, this is the worst possible scenario. We hope and pray that it doesn't happen but such is life sometimes that it does. Our thoughts and prayers go out to all those families affected.
cheers Steve
Although it is true that there is a statistical probability that some mechanical, electrical, or hydraulic device will fail unexpectedly and lead to accidents such as this, it is far more likely that someone will miss the significance of some detail, become rushed and overlook a step in the checklist, or that something will be misinterpreted and will react in a manner that leads to terrible circumstances. The "human factor" is, more often than not, the prime contributor.
But it is also true that when failures happen for whatever reason, it is also the "human factor" that rescues the situation. Skilled professionals with decades of experience are, more often than not, going to be able to compensate for such problems and save the lives of everyone on board. And only the two up front may be the only ones that know.
From the back, with my noise-cancelling headphones and the seven dollar sandwich, and in blissful but acknowledged ignorance of what you are dealing with, I thank you.
Yes, I'll ride on your airplane.
Is it part of pilot training to correlate the failure to achieve lift during a takeoff roll with possible failure to deploy flaps? I realize there's very little time to troubleshoot in that context but it would seem that checking the flaps would be on the short list.
Also, if a pilot were to realize that flaps were not deployed and he's at V2, would deploying them produce enough lift take the plane safely out of ground effect? In other words, would the small % of flaps available as they deploy provide enough additional lift to get the plane safely out of the airpot?
What too late after V2 to do this, the deployment speed is too slow for one thing and the pilots are too busy just trying to fly the plane in most cases..
If they were at V2, the airplane would already be at a flyable speed to lower the nose on the remaining engine and make a slow climb to a safe altitude..
One the the things all of in airlines try NOT to do is be sideline quarterbacks early in in accidents.. we let the investigators do their job, release the tapes so we can all learn were things went bad..
In your question, there is still the aircraft weight to consider, the exact airspedd when they lost the engine, runway remaining, was the airplane configured correctly.. just too many things to consider, with all of it pure speculation.. this is why we dont speculate (aviators)that is.. the press is the polar opposite and can get away with this...
As usualy Dave is dead on right in his assessment..
Dave can correct me if I'm wrong for the big iron. But generally speaking, the training is to address what happens when something out of your control happens, rather than how to fix something you should have done from the checklist.
There have been instances where a resourceful, alert and experienced crew can address these issues. The exact details escape me, but a number of years ago a 727 crew flew too low on approach and clipped some trees. This killed two engines and they looked to be going in short of the runway, but the captain extended flaps at just the right moment.
Of course, there was a 747 accident in Kenya where they took off without slats. They experience pre-stall buffet, raised the gear (to reduce drag) and then got a stall warning before sinking back to the runway. The thinking was that the added drag from all the gear doors opening caused them to slow below stall speed...
Good post Dave. Don't comment much but I read every one of your posts. In essence I'm living my airline career vicariously through your blog.
Good work.
anonymous 935- yes, flap deployment at V2 would help the aircraft fly. Believe it or not, the atmosphere in the flight deck has a direct effect on the safety of the flight. There have been three accidents in 60 years where the crew was arguing about union politics, etc., missed an important item on the checklist, like flaps, then crashed. This information is always suppressed for obvious reasons. Personally, I use the tried and trued... FLAPS, TRIM, FUEL that I learned as a kid.
gps direct- correct assesment, also, the accident you are thinking about is a twin engine MD-80, Hartford, CT. This is a very interesting study and if you have not read the report, please do.
grant- that is probably the best way to live an airline career.
Hi, Dave. I have absolutely no knowledge of the field of aviation (just an armchair fascination), but I love your blog.
Just wanted to share something else scary, but very fortunately, not tragic. My husband was on a redeye from SFO to ORD on 8/23 when the plane experienced a “compressor failure” in the left engine (it was a 767). Although the airline reported very little to the media about the incident, passengers recount both flames coming from the damaged engine and smoke in the cabin prior to landing. Here's a link to an article:
http://www.topix.com/forum/sf/TG9BT8USL13AU6E43
There are many other reports out there, too.
On the tail of the Madrid tragedy, this scared us both very badly.
Maybe a blown compressor isn't a big deal in the world of aviation, but in my mind, the pilots and crew deserve much credit for making sure everyone got back safely.
I don't know if it is directly relevant to this accident or not but this does highlight something I have long thought was not a good practice.
As you know, in recip's you always apply full power for take off every time. You get off the ground and get to a safe altitude as quickly as possible no matter how long the runway is. I have always been leery of the practice in turbines of setting EPR's (partial power) based on a calculated take off distance.
I don't see why increasing TBO should outweigh the common sense practice of not wasting runway. Since turbine TBO's are already so much higher than recip TBO's it makes just that much less sense to me.
I think this is just another case where using full power would have bought the flight crew another 5-10 seconds of time to figure out what was wrong. Whether those extra seconds would have been enough or not no one can ever say. However, off the top of my head I can come up with about 6 accidents that could have been prevented by the routine fire walling of the thrust levers for the take off roll. Normally a few accidents is enough to change SOP but the airline accountants seem very wedded to this particular practice.
Yeah I know, nobody cares what I think about it. :)
Seems that the takeoff run was longer than usual (indicating loss of power). But they went for it, so I guess they had V2? The Flight recorder should tell us that.
The cockpit recorder indicates
loss of (directional?) control, TV reporter here said.
Somehow I'm thinking of that Lauda Air crash where thrust reversal deployed in flight. I wonder if that happened here? Would certainly raise the Vmc speed.
Just speculating, we'll have to wait for the report.
Cum granis salis....
nerdy redneck bob- of course I care what you think, hence allowing comments. I know what you are getting at, but the practice of setting partial power is a good one, in my view, because it lowers stress on the engine. For example, in the southwest on a hot day, it is better to have an EGT of 580 degrees than 635 degrees. As far as runway length goes, most of our runways are in excess of 8,000 feet. Most of our take-off rolls are around 3,000 to 5,000 feet even on hot and heavy days.
I'd much rather use a reduce thrust take off then max blast off a runway if I can help it. There was a figure floating around (and I don't know how true it is) that for the CF34 engine (which powers a whole lot of different airplanes) there had never been a engine failure on take off when using a reduced power setting.
Great blog Dave! I'm with you on this unfortunate crash. And what a surprise to have "eyewitnesses" give inaccurate accounts. It's media driven for sure.
And you're right....a simple FATS check is as valuable as the old GUMPS check was (and still is).
Regarding reduced-thrust takeoffs: I'm with Dave -- I've seen the data on projected failure rates of turbines due to heat.
Another advantage of reduced thrust takeoffs is easier directional control if an engine fails -- less asymmetric thrust to deal with. fwiw
Note – this post is only for conversational purposes, and to hopefully obtain the educated opinion of an experienced airline pilot, not to speculate on the cause of the tragedy, as only an appropriately conducted investigation can reveal that...
Anonymous 9:35's comment about flap extension has taken on a whole new light on this tragedy. The wall street journal reports that sources close to the investigation stated that the flight data recorder (one of the black boxes) revealed that the flaps were not extended for take off. - Dave, would a stall upon leaving ground effect be consistent with the witness accounts (however inaccurate they may be) that one of the wings “dropped” before the aircraft "settled" back onto the runway? I am not familiar with the aerodynamics of big iron wing planform, and how much of a difference there is in between the stall speed at, say, flaps 0 and flaps 15.
I'm not familiar with big iron aerodynamics, but the light twins I fly, I would have felt the missing lift force and stay in the ground effect, is that the same case in wide bodies?
My London newspaper says that flaps were not set, and that an 'electrical fault' prevented the warnings from sounding.
If true how sad and how unecessary.
Dave- off topic, but your opinion would be valuable here.
There have been some cases in England where people have shone lasers at aircraft- mostly police helicopters, but also some airliners.
There's a discussion of this on an English legal blog here:
http://tinyurl.com/5tou45
Some contributors think the danger is exaggerated. What do you think?
Nerd for Justice
anonymous 503- it is very dangerous. I have actually been lasered from the ground. We were on downwind leg, turning left base when some idiot lasered us (about 5 years ago). It hurts and temporarily blinds the eye that got hit. Then you see spots for a few minutes after...
From all the available evidence so far, it appears that the flaps may not have been selected for the planned take-off configuration. This is the only reason for the aircraft to wallow after take-off besides engine problems, which have been ruled out. In case the flaps are not selected then modern sweep back wing aircraft would be very close to their stalling angle at the take off attitude and one of the wings stalling before the other due to various reasons is a distinct possibility leading to the wallowing that was seen. The only other thing that would strengthen/negate this fact would be the condition of the TAKE-OFF CONFIGURATION warning. When the flaps are not in the take-off configuration, an audio alarm should have sounded cautioning the crew.
Another reason could be very aft Centre of Gravity. There has been one fatal accident of a freighter due to this cause, as per my information.
Wow, I can’t believe this post, at least the earth didn’t cave in, that’s the only thing that could have made this accident worse. I had an accident myself not that long ago, I had to hire an accident lawyer in Los Angeles, I was actually able to recoup some of the costs but there’s still a bit of mental damage.
Evertime I see an accident like this it makes me wonder if they violated the sterile cockpit rule. As a passenger, this is the single most important thing I want flying professionals to adhere to. A well-trained pilot follwing the rules in a well-maintained plane should be perfectly safe.
I also believe there were far, far more than 3 accidents in 60 years caused by violation of this rule. Comair was the most recent and tragic. There may be 3 well-known and documented cased but I am sure I have read of more than 3. There are also many near-disasters that were caused by ignoring this important rule.
It is really a huge tragedy...
Our thoughts and prayers go out to all those families affected.
I think Plane's devices must be checked by more persons in order to avoid such a disaster.
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