Lufthansa cargo plane crash
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pof2MDA
You are so right. I mean only to discuss, not pass judgment. Narita video is haunting enough without adding any blame to the airframe.
After the fire, I became transfixed by the Nose Gear strut protruding into the sky from an inverted and burnt out a/c. It occurred to me that the strut was responsible for the instant Pitch up of 30 degrees, and the roll left which caused the inversion. Had the strut collapsed, the Nose would have remained on the ground, and the a/c would have slid to a stop, perhaps. The wings I believe were already broken, from the hard contact; they broke downward, their weak spot.
When the wings were reloaded due the last Pitch Up, they snapped, and the right wing presented gobs more lifting surface to the airmass, hence the rollover.
If you review the video, you might be amazed at the strength of the NoseGear. That it survived is astonishing, at least to me.
You are so right. I mean only to discuss, not pass judgment. Narita video is haunting enough without adding any blame to the airframe.
After the fire, I became transfixed by the Nose Gear strut protruding into the sky from an inverted and burnt out a/c. It occurred to me that the strut was responsible for the instant Pitch up of 30 degrees, and the roll left which caused the inversion. Had the strut collapsed, the Nose would have remained on the ground, and the a/c would have slid to a stop, perhaps. The wings I believe were already broken, from the hard contact; they broke downward, their weak spot.
When the wings were reloaded due the last Pitch Up, they snapped, and the right wing presented gobs more lifting surface to the airmass, hence the rollover.
If you review the video, you might be amazed at the strength of the NoseGear. That it survived is astonishing, at least to me.
fuselage failed aft of wing TE
the wings snapped off
refer the
report pg5,
figure 12 on pg21,
figure 15 pg 23
figure 16 pg 24
1.12.2.2 Main landing gear
The left main landing gear remained intact (Figure 16). The wing rear spar,
upper fixed brace, upper side brace, lower side brace, lock links, strut (PN
NRG6719-501, S/N BFGS 01027) and truck had no visible damage that would
suggest gear failure or strut over-compression. The chrome extension on the
strut measured 4.75 inches (in.) and the paint below the chrome did not
demonstrate signatures of strut over-travel. All four (4) tires were inflated.
The center main landing gear remained relatively intact; however, the aircraft
structure surrounding the gear attach points was largely consumed by fire. The
gear sat slightly forward and to the right of the normal down and locked
position. The strut ( no visible data plate), gear braces and truck had no visible
damage that would suggest gear failure or strut over-compression. The chrome
extension on the strut measured 9.5 in. and the paint below the chrome did not
demonstrate signatures of strut over-travel. The two (2) tires were inflated.
The right main landing gear remained intact. The wing rear spar, upper fixed
brace, upper side brace, lower side brace, lock links, strut (PN NRG6719-501,
S/N BFGS 01028) and truck had no visible damage that would suggest gear
failure or strut over-compression. A piece of speed tape type material was
located just above the junction of the upper side brace and upper fixed brace.
This speed tape was partially peeled back. There was also evidence of an
imprint on the bottom side of a wheel well upper panel that appeared to have
been made by a hinge located on the upper fixed brace. The chrome extension
on the strut measured 4.13 in. and the paint below the chrome did not
demonstrate signatures of strut over-travel. All four (4) tires were inflated
The left main landing gear remained intact (Figure 16). The wing rear spar,
upper fixed brace, upper side brace, lower side brace, lock links, strut (PN
NRG6719-501, S/N BFGS 01027) and truck had no visible damage that would
suggest gear failure or strut over-compression. The chrome extension on the
strut measured 4.75 inches (in.) and the paint below the chrome did not
demonstrate signatures of strut over-travel. All four (4) tires were inflated.
The center main landing gear remained relatively intact; however, the aircraft
structure surrounding the gear attach points was largely consumed by fire. The
gear sat slightly forward and to the right of the normal down and locked
position. The strut ( no visible data plate), gear braces and truck had no visible
damage that would suggest gear failure or strut over-compression. The chrome
extension on the strut measured 9.5 in. and the paint below the chrome did not
demonstrate signatures of strut over-travel. The two (2) tires were inflated.
The right main landing gear remained intact. The wing rear spar, upper fixed
brace, upper side brace, lower side brace, lock links, strut (PN NRG6719-501,
S/N BFGS 01028) and truck had no visible damage that would suggest gear
failure or strut over-compression. A piece of speed tape type material was
located just above the junction of the upper side brace and upper fixed brace.
This speed tape was partially peeled back. There was also evidence of an
imprint on the bottom side of a wheel well upper panel that appeared to have
been made by a hinge located on the upper fixed brace. The chrome extension
on the strut measured 4.13 in. and the paint below the chrome did not
demonstrate signatures of strut over-travel. All four (4) tires were inflated
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No analysis of failure paths? None? I'll have to stop observing the airport vid.
You disagree the Nose Pitched up due the remarkable tenacity of the Nose Gear?
You think it was elevator?
You disagree the Nose Pitched up due the remarkable tenacity of the Nose Gear?
You think it was elevator?
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prof2MDA
What I read was a post that seemed to downplay the discussion. How many times in the past have there been no audio/visual records from the observer's pov? It is an asset, not a resource to downplay.
The chain (visual) is explicit, the forensics unknown at the time. Do we ignore the painful evidence?
There is a reason these cameras exist, and their use is important, albeit open to interpretation, and casual misuse. All records of revenue flight are important, and make progress possible, No?
cheers
What I read was a post that seemed to downplay the discussion. How many times in the past have there been no audio/visual records from the observer's pov? It is an asset, not a resource to downplay.
The chain (visual) is explicit, the forensics unknown at the time. Do we ignore the painful evidence?
There is a reason these cameras exist, and their use is important, albeit open to interpretation, and casual misuse. All records of revenue flight are important, and make progress possible, No?
cheers
pitchin'
Nose Pitched up due the remarkable tenacity of the Nose Gear?
You think it was elevator?
You think it was elevator?
would think that the take away is to avoid large stab inputs at the touchdown point, as we as humans tend to lag the dynamics by enough to get out of sorts. It does appear that had the elevator been held in the flare position for a couple of seconds, and then just washed out towards a neutral flare, that it just would have been a write up and debriefing event.
The simulators we use in general are pretty good, but they are not always representative of the real world in all aspects, even within the normal envelope. The QTG criteria permit a substantial variance from manufacturer dynamics vs the simulators performance. The particular MD11 sim when I evaluated it a long time back was problematic in many respects, particularly given the "advanced" training that was being conducted in it. LH appears to properly acknowledge the fit for purpose issue of the MD11 sim for landing training, and that probably is justified, but has high cost and increased risk.
If you feel like putting in full forward elevator in a flare/landing, I hope it is in the latter part of a J3 rollout, and not in any large conventional gear aircraft. It would be a warning to the system that the technique being employed has associated risks.
The LH aircraft held up rather well, and the crew are indeed fortunate that the MLG/aft spar didn't fail, that would have increased the risk to life considerably. The VS of the HKG MD11 was 1650FPM (IIFC) which is not far out from the third touchdown of this event...
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No evidence of spar failure in Narita crash?
Prof2MDA,
I took the still photos that showed the smoldering wreckage at rest upside down in Narita as a rather strong hint of a failed and folded wing, which was very consistent with what was seen on the grainy security video, and at previous MD11 crashes. The final investigation report seemed to confirm that.
I took the still photos that showed the smoldering wreckage at rest upside down in Narita as a rather strong hint of a failed and folded wing, which was very consistent with what was seen on the grainy security video, and at previous MD11 crashes. The final investigation report seemed to confirm that.
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Originally Posted by FDR
The VS of the HKG MD11 was 1650FPM (IIFC) which is not far out from the third touchdown of this event...
The problem does not seem to be the landing gear strength, but the fact that the MD-11 can have an out of control arrival. This whole bit about having to come in with strong nose down inputs in some landing situations is the core problem. Get your timing off and you can be in a world of hurt.
Having the spoilers pitch your nose up when you should be de-rotating has to be a big part of the handling problem, which was the reason I mentioned the B748 problem and solution earlier. I'm surprised the FAA certified it like that. The aircraft should de-rotate in a more normal fashion.
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Mass/distribution
I think what I'm getting at, and could have started by saying it is that this aircraft may not be a solid candidate for its mission. There appear to be some razor thin certification numbers, pilots are cautioned to be with their A game on approach, etc. She is phenomenally short coupled, which may address why Machinbird has pointed out its reluctance to de-rotate. Aircraft with a centerline Bogie wear a familiar telltale of "Heavy Landing Prep", though that is not a disqualifier. Are the crew getting "behind" on approach, or is she sluggish in PITCH due the long forward moment, and the short swing of the tail feathers?
I saw one FEDEX downwind for SFO from my perch here in the marina. What an absolutely beautiful a/c. She does, however, have issues.
On short final, working the elevators is not good. Instead of PITCH control, the a/c experiences rapid migration of Center of LIFT, followed by a command to de rotate, which merely increases sink?
I wasn't intending to impugn the Landing Gear, Machinbird, strong is good. Just don't expect them to give it up when you bounce, better yet, don't bounce.
I saw one FEDEX downwind for SFO from my perch here in the marina. What an absolutely beautiful a/c. She does, however, have issues.
On short final, working the elevators is not good. Instead of PITCH control, the a/c experiences rapid migration of Center of LIFT, followed by a command to de rotate, which merely increases sink?
I wasn't intending to impugn the Landing Gear, Machinbird, strong is good. Just don't expect them to give it up when you bounce, better yet, don't bounce.
Last edited by Lyman; 1st Mar 2012 at 14:05.
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Lyman
1. It takes a lot more than a video to determine the failure path. A video can provide a data point, and that is all;
2. All long aircraft are subject to tail strike;
3. The control manipulations and wind conditions that have led to the accidents in RIH, EWR and HKG would have led to the same in the other types of aircraft as well.
1. It takes a lot more than a video to determine the failure path. A video can provide a data point, and that is all;
2. All long aircraft are subject to tail strike;
3. The control manipulations and wind conditions that have led to the accidents in RIH, EWR and HKG would have led to the same in the other types of aircraft as well.
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Short coupling attenuates the risk of tail strike. I am not trying to establish a failure path. She does NOT fly "like all other a/c."
Positioning the landing gear has more to do with a very high nose, which is not comfortable in the Flare. Long a/c get long GEAR. The design limits of an a/c are remarkably immune to scale.
I seem to appear as overly critical perhaps. No axe.
Positioning the landing gear has more to do with a very high nose, which is not comfortable in the Flare. Long a/c get long GEAR. The design limits of an a/c are remarkably immune to scale.
I seem to appear as overly critical perhaps. No axe.
Last edited by Lyman; 1st Mar 2012 at 14:34.
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Cyranno,
I agree. It makes no sense to redact the registration, operator, and crew names. Particularly when they listed the serial number of the aircraft and the certificate numbers of the crew. Let's see .... how many German registered MD-11's crashed at Ryadh that day?
Apparently it was requested by the German accident investigation board, who have a history of hiding registration identification. This is happening in the US as well.
I agree. It makes no sense to redact the registration, operator, and crew names. Particularly when they listed the serial number of the aircraft and the certificate numbers of the crew. Let's see .... how many German registered MD-11's crashed at Ryadh that day?
Apparently it was requested by the German accident investigation board, who have a history of hiding registration identification. This is happening in the US as well.
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Sorry, N/A. Here's why: No credentials I have will suffice once this question is demanded. You seek to distract from the discussion. If my questions spark interest, I hope it would be in the discussion, not my logbook.
Last edited by Lyman; 1st Mar 2012 at 17:41.
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Cyranno,
I agree. It makes no sense to redact the registration, operator, and crew names. Particularly when they listed the serial number of the aircraft and the certificate numbers of the crew. Let's see .... how many German registered MD-11's crashed at Ryadh that day?
Apparently it was requested by the German accident investigation board, who have a history of hiding registration identification. This is happening in the US as well.
I agree. It makes no sense to redact the registration, operator, and crew names. Particularly when they listed the serial number of the aircraft and the certificate numbers of the crew. Let's see .... how many German registered MD-11's crashed at Ryadh that day?
Apparently it was requested by the German accident investigation board, who have a history of hiding registration identification. This is happening in the US as well.
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Originally Posted by Lyman
Sorry, N/A.
I believe I saw a post where an alter ego of yours mentioned light twin time??
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Lyman
MD-11 flying experience would, perhaps, not be an issue, however, when you wrote "She does NOT fly "like all other a/c." that begs the question as to what reference you have for that? It is a fair question based on your post.
MD-11 flying experience would, perhaps, not be an issue, however, when you wrote "She does NOT fly "like all other a/c." that begs the question as to what reference you have for that? It is a fair question based on your post.
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Opinions
Everyone is entitled to have his/her opinion about the MD11 and its good and bad sides. But for those who haven´t flown on the type, how can you compare its handling and characteristics with other aircrafts?
I´ve done a couple of thousand hours on it and I really loved flying this machine. We used to call "her" a "Diva". Why? Very simple. Treat her right and you´ll get the reward in form of a stable approach followed by a nice landing. But if, on short final, you let her go below approach speed or have a speed vector pointing way down when the auto throttle pulls the thrust back for the flare (of course you can override the retard) you might be running out of elevator force during the flare resulting most likely in a hard touch down.
But as long as you´re aware of this and remember basic flying it is not a difficult aircraft to fly.
Just my personal ´opinion´.
I´ve done a couple of thousand hours on it and I really loved flying this machine. We used to call "her" a "Diva". Why? Very simple. Treat her right and you´ll get the reward in form of a stable approach followed by a nice landing. But if, on short final, you let her go below approach speed or have a speed vector pointing way down when the auto throttle pulls the thrust back for the flare (of course you can override the retard) you might be running out of elevator force during the flare resulting most likely in a hard touch down.
But as long as you´re aware of this and remember basic flying it is not a difficult aircraft to fly.
Just my personal ´opinion´.
