MK Airlines B747 crash at Halifax
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SNAM
The LE flap indication light on a 747 classic is general, meaning one light for the 20 krueger flaps that are on the plane, with not even a distinction between L or R. One little green light indicates whether your plane will make it into the air in time or not.
But if this LE flaps hypothesis is what happened, the problem is not with the light or the gauges but like on LH540 with the crew. On the Lufty flight both LE flaps lights were extinguished, indicating that the LE flaps were not deployed. The crew failed to take notice, so subsquently the aircraft had difficulties getting airborne and crashed 1100m past the threshold. I'm suggesting that if the MKJ didn't have the suggested modification fitted to alert the crew to the configuration error which -if that is what happened- they failed to pick up initially, the same course of events might be what happened at Halifax.
So to answer your question: if the crew didn't check the position of the LE flaps properly and the suggested modification to the T/O config warning was not implemented, they started the takeoff without LE flaps and with the increased weight compared to the Lufthansa flight the plane would have refused to lift off the relatively short runway and continued roaring down the ground either until it picked up enough airspeed to take off without LE flaps or until she hit something.... regretfully the latter was the case.
On another note though: the eyewitness reports that state the plane was both "really heavy" and at the same time state that is was taking off from a point of decreased runway distance (2000m vs. 2700m) suggest the crew started the takeoff without having enough runway, and found out when it was too late.
The LE flap indication light on a 747 classic is general, meaning one light for the 20 krueger flaps that are on the plane, with not even a distinction between L or R. One little green light indicates whether your plane will make it into the air in time or not.
But if this LE flaps hypothesis is what happened, the problem is not with the light or the gauges but like on LH540 with the crew. On the Lufty flight both LE flaps lights were extinguished, indicating that the LE flaps were not deployed. The crew failed to take notice, so subsquently the aircraft had difficulties getting airborne and crashed 1100m past the threshold. I'm suggesting that if the MKJ didn't have the suggested modification fitted to alert the crew to the configuration error which -if that is what happened- they failed to pick up initially, the same course of events might be what happened at Halifax.
So to answer your question: if the crew didn't check the position of the LE flaps properly and the suggested modification to the T/O config warning was not implemented, they started the takeoff without LE flaps and with the increased weight compared to the Lufthansa flight the plane would have refused to lift off the relatively short runway and continued roaring down the ground either until it picked up enough airspeed to take off without LE flaps or until she hit something.... regretfully the latter was the case.
On another note though: the eyewitness reports that state the plane was both "really heavy" and at the same time state that is was taking off from a point of decreased runway distance (2000m vs. 2700m) suggest the crew started the takeoff without having enough runway, and found out when it was too late.
Last edited by A-FLOOR; 17th Oct 2004 at 19:48.
Phileas,
<<I think you'd be surprised how many Ops guys understand little about route planning and computerised flight planning, many have been trained only to tap the right buttons without understanding the theory behind it.
>>
Not where I come from, luckily. I'd certainly feel less than enthusiastic working in such an environment. In any event, a recheck of RTOW by the crew would be expected before any departure, especially on a comparatively short runway such as this one.
It is as you say, I have been on and around longhaul planes for the better part of 20 years and 2700m and a max gross (insert widebody type) are not what I would expect to compute.
Ah well, we'll know soon enough I guess.
Best regards
AN2 Driver
<<I think you'd be surprised how many Ops guys understand little about route planning and computerised flight planning, many have been trained only to tap the right buttons without understanding the theory behind it.
>>
Not where I come from, luckily. I'd certainly feel less than enthusiastic working in such an environment. In any event, a recheck of RTOW by the crew would be expected before any departure, especially on a comparatively short runway such as this one.
It is as you say, I have been on and around longhaul planes for the better part of 20 years and 2700m and a max gross (insert widebody type) are not what I would expect to compute.
Ah well, we'll know soon enough I guess.
Best regards
AN2 Driver
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A floor, I was asked to post this tread by a member of this board and the board I frequent due to the amount of pure speculation going on in here. I read, too late that someone had done it for me.
I haven't read every post in this thread but I must say there are some real "experts" in here...
Cheers.
I haven't read every post in this thread but I must say there are some real "experts" in here...
Cheers.
Usual disclaimers apply!
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Just a couple of minor points ref the LH accident, there were 2 parts to the SB for the leading edge flaps one as described was the config warning and the other more important was that on the early classics it was possible to start the engines without selecting the pylon (bleed air) valve switches to on first. Therefore it was possible to start the engines with the pylon valves selected closed with only the reverse flow solenoid opening the valve until the start switch was released.
There is not only the leading edge flap lights on the P2 panel but also the annunciator on the FE panel which has amber (transit) and green (extended) flap motor position lights.
There is not only the leading edge flap lights on the P2 panel but also the annunciator on the FE panel which has amber (transit) and green (extended) flap motor position lights.
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RCMP help find crashed jet's data recorder
CTV.ca News Staff
Thanks to a break in the weather, search teams have found the black box of a cargo jet that crashed at Halifax's International Airport last week.
RCMP helped with the search by taking advantage of Sunday's dry weather to move heavy equipment into the crash site.
Bill Fowler of the Transportation Safety Board is calling the discovery of the flight data recorder a break in the investigation, but said they are still looking for the cockpit voice recorder.
The recorder will be taken to TSB headquarters in Ottawa, where it will be examined.
Fowler told a news conference that the data recorder might have suffered some heat damage.
"We are not certain of the integrity of the data, but certainly this is an important milestone in our investigation," Fowler said.
The cargo jet crashed in flames off the end of a runway last week. So far investigators know that the tail of the plane hit the runway. They aren't sure why.
CTV.ca News Staff
Thanks to a break in the weather, search teams have found the black box of a cargo jet that crashed at Halifax's International Airport last week.
RCMP helped with the search by taking advantage of Sunday's dry weather to move heavy equipment into the crash site.
Bill Fowler of the Transportation Safety Board is calling the discovery of the flight data recorder a break in the investigation, but said they are still looking for the cockpit voice recorder.
The recorder will be taken to TSB headquarters in Ottawa, where it will be examined.
Fowler told a news conference that the data recorder might have suffered some heat damage.
"We are not certain of the integrity of the data, but certainly this is an important milestone in our investigation," Fowler said.
The cargo jet crashed in flames off the end of a runway last week. So far investigators know that the tail of the plane hit the runway. They aren't sure why.
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A-FLOOR: Thanks for the link.
gas path: I don't think that the F/E (Lufty at NBO) necessarily had to have started the engines, as you had said, with the pylon bleed air valves deliberately closed, as it is not a normal procedure to turn off the bleeds. A more likely scenario was that he had turned the bleeds off during taxi-out (backtrack on Rwy) just as the flaps were lowered to Ten degrees. (No 2 Pack could continuously have been powered from APU air with isolation valves closed). Perhaps because of the high altitude airport, Lufty's procedure, or the captain's preference, was to take-off with the bleeds off to extract max thrust from the engines.
But Captain Krack's response on the CVR (from A-FLOOR's attached link on his previous post) to the Flaps callout was: "10/10 and GREEN." So whether he had actually seen the green LE light, or whether he had just answered a conditioned response, it was undetected by the F/E and F/O.
gas path: I don't think that the F/E (Lufty at NBO) necessarily had to have started the engines, as you had said, with the pylon bleed air valves deliberately closed, as it is not a normal procedure to turn off the bleeds. A more likely scenario was that he had turned the bleeds off during taxi-out (backtrack on Rwy) just as the flaps were lowered to Ten degrees. (No 2 Pack could continuously have been powered from APU air with isolation valves closed). Perhaps because of the high altitude airport, Lufty's procedure, or the captain's preference, was to take-off with the bleeds off to extract max thrust from the engines.
But Captain Krack's response on the CVR (from A-FLOOR's attached link on his previous post) to the Flaps callout was: "10/10 and GREEN." So whether he had actually seen the green LE light, or whether he had just answered a conditioned response, it was undetected by the F/E and F/O.
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McGinty - without questioning your reasons, or qualifications, why would you only suspect "some failure regarding flap config"?
king air guy - if "3 sources (pilots, loadmaster, linecrew) confirmed the load, and albeit heavy, on paper was not overweight + was within C of G limits", why on earth would the operating crew decide on an intersection take-off "as reported by line crews"? Come on guys, on a 2700m runway, I hardly think that's likely?
king air guy - if "3 sources (pilots, loadmaster, linecrew) confirmed the load, and albeit heavy, on paper was not overweight + was within C of G limits", why on earth would the operating crew decide on an intersection take-off "as reported by line crews"? Come on guys, on a 2700m runway, I hardly think that's likely?
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king air guy - but your later comment of there being some real "experts" on this thread is oh so true! Too many bored people with too much time on their hands perhaps? To those experts - get a grip, get objective, and get off the wagon!
A-Floor
A wrong turn? I don't know if you've seen the airport chart, but how hard is it to get confused between three taxiways? Middle of the night or not, I think if they had conferred and agreed that they were heavy (as the "linecrew" said they had), then they would have all been particularily aware of where to taxi? This whole leading-edge theory bothers me too - how many times does a group of people in a 747-200F have to check the LE devices in order to satisfy the "experts" out there? The NBO crash was so long ago, and all those lessons have been deliberated for so long, just for them to all be brought out and dusted off now that another one has had an accident on take-off? Surely all the pilots that this concerns might have learned from that one guys? Any other theories?
Tan
Thanks for the update on the black-box recovery
A-Floor
A wrong turn? I don't know if you've seen the airport chart, but how hard is it to get confused between three taxiways? Middle of the night or not, I think if they had conferred and agreed that they were heavy (as the "linecrew" said they had), then they would have all been particularily aware of where to taxi? This whole leading-edge theory bothers me too - how many times does a group of people in a 747-200F have to check the LE devices in order to satisfy the "experts" out there? The NBO crash was so long ago, and all those lessons have been deliberated for so long, just for them to all be brought out and dusted off now that another one has had an accident on take-off? Surely all the pilots that this concerns might have learned from that one guys? Any other theories?
Tan
Thanks for the update on the black-box recovery
Last edited by csomesense; 18th Oct 2004 at 00:08.
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csomesense
Welcome to PPRuNe.
Your profile indicates you just joined, have two posts so far, both of them is this topic, and fly 747s and DC-8s for a living. Something you want to tell us perhaps?
While I don't know if you somehow knew the guys who lost their lives in this tragic accident, we are all very sorry this happened and I can assure you our thoughts are with them.
But however understandable, there is absolutelty no need to take your frustrations out on me or anyone of us simply because we like to talk about the possibilities as to why this happened.
Your profile indicates you just joined, have two posts so far, both of them is this topic, and fly 747s and DC-8s for a living. Something you want to tell us perhaps?
While I don't know if you somehow knew the guys who lost their lives in this tragic accident, we are all very sorry this happened and I can assure you our thoughts are with them.
But however understandable, there is absolutelty no need to take your frustrations out on me or anyone of us simply because we like to talk about the possibilities as to why this happened.
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A-Floor
Thank you for your welcome.
As you and I know well, it is very easy to assume you know a candidate by viewing their profile. But how easy is it to register under a new name with any relevant criteria to fit a profile? Haven't we met before? Is there anyone in your past who has questioned your motives, causing you to jump and check? The obvious may not be as simple as you first think. All I'm asking is that you answer the questions asked, not the profile where they come from!
see your pm!
Thank you for your welcome.
As you and I know well, it is very easy to assume you know a candidate by viewing their profile. But how easy is it to register under a new name with any relevant criteria to fit a profile? Haven't we met before? Is there anyone in your past who has questioned your motives, causing you to jump and check? The obvious may not be as simple as you first think. All I'm asking is that you answer the questions asked, not the profile where they come from!
see your pm!
Last edited by csomesense; 18th Oct 2004 at 02:02.
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Ofcourse you are totally right, but I must say that regging on a forum time after time just to put people in their place is a very silly thing to do, and neither do I expect anyone I see on the forums I frequent who might be new to be someone from my past who has come to haunt me or something 
So, to answer your question: As I've mentioned in this topic and as you might have read in my profile I'm a student in aerospace engineering. Personally, I don't think there is anything wrong with theorizing a case to try to explain what happened with the limited information that is available to us, and I don't think that my LH540 comparison is excessive, as you might have noticed that the two accidents appear to be very similar and involve the same type of aircraft.
So until the proper facts are presented to us by the people who are rightfully in charge of this, theorizing is all we can do to try to and quench the thirst for answers.
So, to answer your question: As I've mentioned in this topic and as you might have read in my profile I'm a student in aerospace engineering. Personally, I don't think there is anything wrong with theorizing a case to try to explain what happened with the limited information that is available to us, and I don't think that my LH540 comparison is excessive, as you might have noticed that the two accidents appear to be very similar and involve the same type of aircraft.
So until the proper facts are presented to us by the people who are rightfully in charge of this, theorizing is all we can do to try to and quench the thirst for answers.
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A-Floor
see your pm.
Rather than bog this thread down with endless "clever" use of the English language - let's examine the possibilities. Don't get all caught up on the mis-config theory, but rather examine other things which might have gone wrong. As you said, until the relevant authorities tell us what actually happened, all we can do is speculate. But three pages of threads on the same topic is going nowhere fast - rather open other avenues which other people might be interested in?
Do you think we could interest anyone else out there to comment on any other theories - load shift, mis-bugging, engine failures (according to ground "witnesses", there was an "explosion" heard?) In my recent experience of aircraft accidents, 747's don't just run off the end of runways, and I don't think this particular company's crew training can be that much different from anyone else's in the world?
see your pm.
Rather than bog this thread down with endless "clever" use of the English language - let's examine the possibilities. Don't get all caught up on the mis-config theory, but rather examine other things which might have gone wrong. As you said, until the relevant authorities tell us what actually happened, all we can do is speculate. But three pages of threads on the same topic is going nowhere fast - rather open other avenues which other people might be interested in?
Do you think we could interest anyone else out there to comment on any other theories - load shift, mis-bugging, engine failures (according to ground "witnesses", there was an "explosion" heard?) In my recent experience of aircraft accidents, 747's don't just run off the end of runways, and I don't think this particular company's crew training can be that much different from anyone else's in the world?
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In response to csomesense's question: McGinty - without questioning your reasons, or qualifications, why would you only suspect "some failure regarding flap config"?
As with many others. I cannot help but speculate on the underlying causes of tragedies such as this particular crash, especially in the absence of hard data. Puzzles such as this naturally draw the curious into speculation as to the cause.
As noted in my first post, if this accident had occured in the midst of winter, then one would immediately suspect that icing might be the primary cause of a failure of a modern airliner to achieve sufficent lift to become airborne at a Canadian airport.
Given the absence of icing, there are really only three possible causes: c of g out of whack (including possible load shift); insufficent thrust; or insufficient lift.
It is difficult to imagine that the c of g was out of whack if the plane was fully loaded, given the description of the cargo. Similarly, if the plane was full of pallets, it is difficult to imagine anything that would stimulate a major load shift. A few empty spots would be required for a destabilising load shift to take place.
Regarding insufficent thrust, there are no eyewitness reports of unusual sounds or sights regarding engine performance prior to the plane hitting the berm. In addition, the kinetic energy of the plane was clearly very high, given how far it ploughed through the forest at the end of the runway. Also, there are no reports of any engine debris on the field prior to the collision with the berm.
All in all, my curiosity leads me to think that this plane just did not have enough lift, the two tail strikes indicating a desperate attempt to get the thing off the ground.
There are a number of accidents in modern times of planes not leaving the ground or barely getting airborne, and nearly all of them seem to have involved flap problems when icing was ruled out as a possible cause.
Just my guess, and of course there may be other compounding elements that may be revealed in due course.
As with many others. I cannot help but speculate on the underlying causes of tragedies such as this particular crash, especially in the absence of hard data. Puzzles such as this naturally draw the curious into speculation as to the cause.
As noted in my first post, if this accident had occured in the midst of winter, then one would immediately suspect that icing might be the primary cause of a failure of a modern airliner to achieve sufficent lift to become airborne at a Canadian airport.
Given the absence of icing, there are really only three possible causes: c of g out of whack (including possible load shift); insufficent thrust; or insufficient lift.
It is difficult to imagine that the c of g was out of whack if the plane was fully loaded, given the description of the cargo. Similarly, if the plane was full of pallets, it is difficult to imagine anything that would stimulate a major load shift. A few empty spots would be required for a destabilising load shift to take place.
Regarding insufficent thrust, there are no eyewitness reports of unusual sounds or sights regarding engine performance prior to the plane hitting the berm. In addition, the kinetic energy of the plane was clearly very high, given how far it ploughed through the forest at the end of the runway. Also, there are no reports of any engine debris on the field prior to the collision with the berm.
All in all, my curiosity leads me to think that this plane just did not have enough lift, the two tail strikes indicating a desperate attempt to get the thing off the ground.
There are a number of accidents in modern times of planes not leaving the ground or barely getting airborne, and nearly all of them seem to have involved flap problems when icing was ruled out as a possible cause.
Just my guess, and of course there may be other compounding elements that may be revealed in due course.
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Gentlemen..
I feel compelled to dispel any rumors and speculations regarding this aeroplane, which I personally have flown under an earlier tail number.
1) The leading edge devices are not slats at all, they are leading edge flaps. There are 4 on each wing and there are individual annunciator lights on the Flight Engineer's panel (Fondly referred to as 'Nairobi Lights, as they were fitted after the Nairobi incident), repeating to a master light on the pilots forward panel which will illuminate amber for any ONE OR MORE leading edge out of agreement with selected flap position.
2) The aircraft in question was fitted with a takeoff warning horn to alert the crew to any configuration deviations.
The chances of the crew failing to observe two different warnings (Aural and Annunciator) are slim, but naturally not impossible.
I would like to say for the second time on this forum, that investigation is best left to professionals who have access to relevant info, and speculation is best pursued around a few drinks, where no-one is taking notes of all the dumb ideas we come up with...
I feel compelled to dispel any rumors and speculations regarding this aeroplane, which I personally have flown under an earlier tail number.
1) The leading edge devices are not slats at all, they are leading edge flaps. There are 4 on each wing and there are individual annunciator lights on the Flight Engineer's panel (Fondly referred to as 'Nairobi Lights, as they were fitted after the Nairobi incident), repeating to a master light on the pilots forward panel which will illuminate amber for any ONE OR MORE leading edge out of agreement with selected flap position.
2) The aircraft in question was fitted with a takeoff warning horn to alert the crew to any configuration deviations.
The chances of the crew failing to observe two different warnings (Aural and Annunciator) are slim, but naturally not impossible.
I would like to say for the second time on this forum, that investigation is best left to professionals who have access to relevant info, and speculation is best pursued around a few drinks, where no-one is taking notes of all the dumb ideas we come up with...
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Airguitar,
Your statement, "that (the) investigation is best left to professionals who have access to relevant info" is the best statement that I have read so far concerning this accident.
Good on ya, mate!
One thing is for sure-there was not enough runway available for WHATEVER configuration they were in, i.e. intersection departure, loss of thrust or low thrust on one or more engines, flaps not in the proper position for this departure or more weight for this aircraft on this runway. I can't think of many other possibilities.
I need to correct you on one statement. The -200 (not sure on the -400) has 20 leading edge flaps, 10 on each side-not 4. They are in 4 groups.
classic
Your statement, "that (the) investigation is best left to professionals who have access to relevant info" is the best statement that I have read so far concerning this accident.
Good on ya, mate!
One thing is for sure-there was not enough runway available for WHATEVER configuration they were in, i.e. intersection departure, loss of thrust or low thrust on one or more engines, flaps not in the proper position for this departure or more weight for this aircraft on this runway. I can't think of many other possibilities.
I need to correct you on one statement. The -200 (not sure on the -400) has 20 leading edge flaps, 10 on each side-not 4. They are in 4 groups.
classic
Airguitar, whilst you are of course quite right, this is an aviation forum. It will always be a human trait to be curious about what may have caused an accident. Discussing the subject in a bar will only involve a handful of people at best. This forum advances the opportunity for many more to air their theories and for others (often professional pilots) to support or discount them. A good example is your own answer about what features the a/c was equipped with based on your “hands-on” experience of the a/c concerned. We all know that we will have to wait for the final report to know what actually did happen. That though will be a long time coming. In the meantime humans will speculate, pilots just as much as non-pilots. I think that we are all mature enough to understand that it is just that: speculation.
