747Whale
Posts: 271
Joined: Fri Dec 07, 2018 7:41 pm

Re: What would have made the MD11 safer?

Thu Dec 13, 2018 2:56 pm

The design isn't weak. But it's good t0 have your expert input on the matter.

It's really a shame that you weren't able to counsel the designers, but there's still time to educate the crews who fly them daily. Most would jump at the chance to gain your insight, one would think.

Sounds like you've got it all figured out.

Max Q wrote:
You have provided a lot of informative context and are very loyal to the aircraft, that’s not uncommon


I'm not "loyal" to the aircraft. it's a chunk of metal, rubber, steel, and carbon.

It's just that I know what I'm talking about, and I'm qualified to talk about it. That maybe what's got you confused. My information didn't come from reading about it on the internet.

Max Q wrote:
Blaming them for the weakness of the design is unfortunate and unfair though


Nothing I've said involves blame. Just facts. There's a difference.

Max Q wrote:
And despite your detailed and comprehensive defence that’s what it is by any standard, you claim it does ‘not have a weak structure’ so how do you explain several landing accidents where the wing spar failed and the aircraft rolled over ?


You don't read or comprehend very well.

Already explained. I linked a video. It's clear that the crew drove the aircraft into the runway after inciting a pilot induced oscillation, and crashed the airplane. That's not a weak structure. That's a crash.

Max Q wrote:
I’ve seen my share of hard and harder landings, some where the aircraft had been flared so late the aircraft was basically flown into the ground and yes I’ve done a few myself


That wasn't a hard landing. It was a crash. Now you're attempting to assert experience, after saying it wasn't necessary, because after all, you can read accident reports, and are therefore an expert.

Except you don't have that experience. Make up your mind.

Max Q wrote:
In other words, if you’d been in any of the Boeing 7 series and done the same thing you might bend something but you’re not going to have a fatal accident


Woulda. Coulda. Shoulda. They crashed the damn airplane. It wasn't a hard landing. It was a crash.

Aircraft frequently break up in a crash. Duh.


Max Q wrote:
If you’ve read ‘handling the big jets’
one of the points the author repeats throughout the book is that a transport aircraft should be designed for an average pilot, a higher than normal level of skill must not be expected or needed due to inadequacies in the design and there’s quite a few average pilots even at the major airlines


Of course I've read it.

The author had a love affair with the B747, and what's not to love. I've been a captain on it, myself. But we're not really talking about the 747, and a lengthy treatise about it is really quite irrelevant. The MD-11 continues to be flown daily by experienced and inexperienced pilots alike.

What's really needed is your expertise. There are no more passenger MD11 operations; they're all cargo. The cargo operations are full of pilots with 10-20 years experience on type, who fly them every day, and who have been responsible for setting up multiple training programs and standing up entire MD11 programs at multiple operators. What the operators really need is someone like yourself, who has no experience in type, no rating or qualification, to show them the danger, the error, and help them understand. Perhaps you could help modify some of the training programs, show them their mistakes and errors, teach them how dangerous the aircraft really is, and save some lives. Be sure to mark on your introductory letter that you read about it on the internet. If that doesn't send them scrambling to bring you onboard to counsel them, nothing will.

Max Q wrote:
And after all, you can know the aircraft inside out but even the best pilots have bad days, fly exhausted, misjudge a flare and or suffer a combination of these factors and others


Stupidity hurts.

Error hurts.

Your commentary reminds me of a senior pilot at a major global carrier who approached me about flying fires (I have a fairly extensive background with fire aviation). He told me he wasn't far from retirement, and thought it looked like something fun to do when he retired. He asked me to tell him about the industry. I did. When I was done, he asked if anyone knew how dangerous it was. He said he was horrified and was going to begin a crusade to let everyone know. He planned to write letters to the FAA to warn them about those dangerous fire operations, contact the media, get the word out because good god, how could anyone ever allow something like that.

Not all things in life are so forgiving as to be made of foam rubber, surrounded by white horses and rainbows, and move at the speed of blubber to prevent injury or a scratch. As pilots, when we get in the cockpit, we're responsible for the safe outcome of the flight: we get paid for our judgement, and for delivering the airplane safely to it's next point of landing. Failure to deliver it safely is on account of many possibilities, but the consequences are usually severe.

It's unfortunate that you won't be able to convince the MD11 community to ground their fleets, but perhaps they just don't know what you know, and once they do, they'll immediately park the aircraft, shutter the simulators, and send the crews off for some well needed vacation and post traumatic stress debriefing. Possibly some extended counseling, so that they may learn just how close to death they've been living.

It's fortunate for you that you're unexposed to the danger of such a poorly designed, underbuilt aircraft, but you should probably take the precaution of not living near airports where the MD11 operates, or under any airways possibly used by the MD11, lest one fall on you. They must be raining down en masse.

Thank you for the education. I've flown 80+ different aircraft types, so far not "loyal" to a single one of them, but all I can say is thank god you've been able to educate me on the type design, so that I'll know to stay away from it in future. I can only imagine what might have happened had I not been schooled on this important matter.

Have you considered writing a white paper?
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Thu Dec 13, 2018 5:13 pm

I'll paraphrase. Not a pilot, but my understand is that with any aircraft the flight manual is validated by the manufacture to the satisfaction of the FAA and as long as you stay within the validated flight envelope you are golden barring any unforeseen events. With any aircraft, if you let the airplane "get ahead of you", very likely you will not have a good day.
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Thu Dec 13, 2018 8:56 pm

A minor clarification, I analogized the MD-11 to the Chevy Corvair, i.e., certain situations (e.g., sudden steering inputs, esp. on reverse cambered roads, for the Corvair; certain inputs during flare for the MD-11) produced unexpected (sometimes lethal) results. I didn't say the MD-11 was the Corvair of the Air. With training, one could operate Corvairs or MD-11s at the edge of their envelopes. The average "driver" didn't have such training before the training on the type was expanded to address "lessons learned".
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 3:13 am

Yup. The Corvair was not understood by people that were use to driving American cars of the day. A lot of the incidents with the MD11 were sloppy airmanship, because on any plane you fly you have to be type rated on it so you should fully understand the characteristics of how it flys before you are allowed to fly it, not so with the Corvair.
 
Max Q
Topic Author
Posts: 6968
Joined: Wed May 09, 2001 12:40 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 8:51 am

747Whale wrote:
The design isn't weak. But it's good t0 have your expert input on the matter.

It's really a shame that you weren't able to counsel the designers, but there's still time to educate the crews who fly them daily. Most would jump at the chance to gain your insight, one would think.

Sounds like you've got it all figured out.

Max Q wrote:
You have provided a lot of informative context and are very loyal to the aircraft, that’s not uncommon


I'm not "loyal" to the aircraft. it's a chunk of metal, rubber, steel, and carbon.

It's just that I know what I'm talking about, and I'm qualified to talk about it. That maybe what's got you confused. My information didn't come from reading about it on the internet.

Max Q wrote:
Blaming them for the weakness of the design is unfortunate and unfair though


Nothing I've said involves blame. Just facts. There's a difference.

Max Q wrote:
And despite your detailed and comprehensive defence that’s what it is by any standard, you claim it does ‘not have a weak structure’ so how do you explain several landing accidents where the wing spar failed and the aircraft rolled over ?


You don't read or comprehend very well.

Already explained. I linked a video. It's clear that the crew drove the aircraft into the runway after inciting a pilot induced oscillation, and crashed the airplane. That's not a weak structure. That's a crash.

Max Q wrote:
I’ve seen my share of hard and harder landings, some where the aircraft had been flared so late the aircraft was basically flown into the ground and yes I’ve done a few myself


That wasn't a hard landing. It was a crash. Now you're attempting to assert experience, after saying it wasn't necessary, because after all, you can read accident reports, and are therefore an expert.

Except you don't have that experience. Make up your mind.

Max Q wrote:
In other words, if you’d been in any of the Boeing 7 series and done the same thing you might bend something but you’re not going to have a fatal accident


Woulda. Coulda. Shoulda. They crashed the damn airplane. It wasn't a hard landing. It was a crash.

Aircraft frequently break up in a crash. Duh.


Max Q wrote:
If you’ve read ‘handling the big jets’
one of the points the author repeats throughout the book is that a transport aircraft should be designed for an average pilot, a higher than normal level of skill must not be expected or needed due to inadequacies in the design and there’s quite a few average pilots even at the major airlines


Of course I've read it.

The author had a love affair with the B747, and what's not to love. I've been a captain on it, myself. But we're not really talking about the 747, and a lengthy treatise about it is really quite irrelevant. The MD-11 continues to be flown daily by experienced and inexperienced pilots alike.

What's really needed is your expertise. There are no more passenger MD11 operations; they're all cargo. The cargo operations are full of pilots with 10-20 years experience on type, who fly them every day, and who have been responsible for setting up multiple training programs and standing up entire MD11 programs at multiple operators. What the operators really need is someone like yourself, who has no experience in type, no rating or qualification, to show them the danger, the error, and help them understand. Perhaps you could help modify some of the training programs, show them their mistakes and errors, teach them how dangerous the aircraft really is, and save some lives. Be sure to mark on your introductory letter that you read about it on the internet. If that doesn't send them scrambling to bring you onboard to counsel them, nothing will.

Max Q wrote:
And after all, you can know the aircraft inside out but even the best pilots have bad days, fly exhausted, misjudge a flare and or suffer a combination of these factors and others


Stupidity hurts.

Error hurts.

Your commentary reminds me of a senior pilot at a major global carrier who approached me about flying fires (I have a fairly extensive background with fire aviation). He told me he wasn't far from retirement, and thought it looked like something fun to do when he retired. He asked me to tell him about the industry. I did. When I was done, he asked if anyone knew how dangerous it was. He said he was horrified and was going to begin a crusade to let everyone know. He planned to write letters to the FAA to warn them about those dangerous fire operations, contact the media, get the word out because good god, how could anyone ever allow something like that.

Not all things in life are so forgiving as to be made of foam rubber, surrounded by white horses and rainbows, and move at the speed of blubber to prevent injury or a scratch. As pilots, when we get in the cockpit, we're responsible for the safe outcome of the flight: we get paid for our judgement, and for delivering the airplane safely to it's next point of landing. Failure to deliver it safely is on account of many possibilities, but the consequences are usually severe.

It's unfortunate that you won't be able to convince the MD11 community to ground their fleets, but perhaps they just don't know what you know, and once they do, they'll immediately park the aircraft, shutter the simulators, and send the crews off for some well needed vacation and post traumatic stress debriefing. Possibly some extended counseling, so that they may learn just how close to death they've been living.

It's fortunate for you that you're unexposed to the danger of such a poorly designed, underbuilt aircraft, but you should probably take the precaution of not living near airports where the MD11 operates, or under any airways possibly used by the MD11, lest one fall on you. They must be raining down en masse.

Thank you for the education. I've flown 80+ different aircraft types, so far not "loyal" to a single one of them, but all I can say is thank god you've been able to educate me on the type design, so that I'll know to stay away from it in future. I can only imagine what might have happened had I not been schooled on this important matter.

Have you considered writing a white paper?




That’s about the most long winded, pompous and dramatic speech I’ve read in regards to the MD 11



You certainly love to write, prolific doesn’t come close to your contributions on this site in the brief time you’ve been posting
on this site with that user name, however you’ll find that getting your point over is far more effective when you don’t attempt to belittle other posters



With your self described vast amount of experience on infinite types you’d think you’d learn a thing or two about putting your views forward and conversing with others




I started this topic with a view to soliciting opinions on what could have made this aircraft safer, suggest you go back and read that, Instead you’ve decided to absorb any negative comments as a personal insult
I’d suggest rethinking that tack and opening your mind a little




It’s apparent you have a real affection for the MD11 good for you, I get that and feel the same way about many types I’ve flown




But that doesn’t change the poor incident and accident history of this type whether it’s myself highlighting that or others
Last edited by Max Q on Fri Dec 14, 2018 9:14 am, edited 2 times in total.
The best contribution to safety is a competent Pilot.
 
WIederling
Posts: 7333
Joined: Sun Sep 13, 2015 2:15 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 8:53 am

stratclub wrote:
Yup. The Corvair was not understood by people that were use to driving American cars of the day. A lot of the incidents with the MD11 were sloppy airmanship, because on any plane you fly you have to be type rated on it so you should fully understand the characteristics of how it flys before you are allowed to fly it, not so with the Corvair.


I've just looked over the design.
That is a road handling desaster.
Pendelachse, no rollbar, bias ply tires, soft "schwabbelig" suspension.
( if they had used the Mercedes kind of "Pendelachse" that has the articulation
very low over the road then maybe. but no roll bar? )

Beetle is problematic. But that Corvair must have been a death trap.
Murphy is an optimist
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 9:23 am

"Unsafe at Any Speed" The Corvair was a deathtrap.
https://www.amazon.com/Unsafe-Any-Speed ... er+corvair
As I commented above... I rolled a Corvair at 30 mph trying to make a tight turn on a reverse camber corner. I was lucky. My friends and I got out, pushed it right side up, and drove home. I had some explaining to do about how the roof got so crumpled, with only scratches on the side.
 
747Whale
Posts: 271
Joined: Fri Dec 07, 2018 7:41 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 2:44 pm

Max Q wrote:

That’s about the most long winded, pompous and dramatic speech I’ve read in regards to the MD 11


That's all you've ever done with the MD-11, isn't it? Read.

An expert reader, then. The industry needs more experts who learned everything they know by reading about it on the internet.

Max Q wrote:
I started this topic with a view to soliciting opinions on what could have made this aircraft safer, blah, blah, blah


You started the topic biased, and your comments are based on little more than an opinion you've formed, without a leg to stand upon on the subject. You know squat about the design, it's handling, training, or any other aspect, and thus far, nearly everything you've had to say about it has been wrong. That you keep pushing deeper into wrong to defend the incorrect speaks volumes about where you stand on the matter. Otherwise, it would have been dropped by now. You don't know what you're talking about, but you're damn proud to do it anyway.

Yes, a civil discourse is more of a slap down in your case, because rather than admit it, you're quite dogged in your desire to drive home a hollow point about which you know nothing and have no experience. You're very quick to dismiss those who do know something about the design, or are type rated, who have experience, and training in the type, in favor of what you think you know from reading snippets off the internet.

You're about 15' deep and still digging deeper. How deep will this hole go?
 
Flighty
Posts: 9926
Joined: Thu Apr 05, 2007 3:07 am

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 4:02 pm

You guys your personal comments are not relevant. Both perspectives are interesting. You are both bringing value. It is great to know both what the M11 did well and what weaknesses it may have. And arguing those points is very interesting to read. The fact you may not agree is not necessarily a bad thing.
 
BravoOne
Posts: 2988
Joined: Fri Apr 12, 2013 2:27 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 7:22 pm

The MD11 had a glass jaw did not suffer poor airmanship as well some of the aircraft of it's time. I welcome 747 Whale's perspective and am a little amazed at Max's remarks.
 
User avatar
OneSexyL1011
Posts: 191
Joined: Thu Jan 21, 2016 8:10 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 7:50 pm

747Whale , Thank you for your experienced opinion, its good to hear such info from a long time expert on the aircraft.
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Fri Dec 14, 2018 8:46 pm

WIederling wrote:
stratclub wrote:
Yup. The Corvair was not understood by people that were use to driving American cars of the day. A lot of the incidents with the MD11 were sloppy airmanship, because on any plane you fly you have to be type rated on it so you should fully understand the characteristics of how it flys before you are allowed to fly it, not so with the Corvair.


I've just looked over the design.
That is a road handling desaster.
Pendelachse, no rollbar, bias ply tires, soft "schwabbelig" suspension.
( if they had used the Mercedes kind of "Pendelachse" that has the articulation
very low over the road then maybe. but no roll bar? )

Beetle is problematic. But that Corvair must have been a death trap.

Oh, you mean you "cherry picked" what suited your point of view? The Corvair was effectively killed by Ralf Nader a man that didn't even have a drivers license. I guess we should take double decker buses and cement trucks off the road because they are death traps when driven beyond their handling capability.

https://en.wikipedia.org/wiki/Chevrolet_Corvair#Handling_issues
[While the Corvair sedan offered competent handling,[26] "the average buyer more accustomed to front-engined cars, did not take [into] account the car's different handling characteristics."[27] Chevrolet made a succession of improvements to the first-generation Corvair suspension. For the 1962 model year, the front anti–roll bar became available as an option. For the 1964 model year, the front anti-roll bar became standard equipment and the rear suspension was modified to include a camber compensating, transverse-mounted leaf spring extending between the rear wheels to limit rear wheel camber change, and carrying much of the rear weight combined with softer coil springs.

For the 1965 model year, the Corvair received a fully independent rear suspension closely resembling that of the contemporary Corvette. The redesigned suspension reduced the rear roll center to half its previous height, using fully articulated half-axles that offered constant camber on the rear tires in all driving situations. This virtually eliminated the handling problems of the first-generation models].
 
Max Q
Topic Author
Posts: 6968
Joined: Wed May 09, 2001 12:40 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 2:03 am

747Whale wrote:
Max Q wrote:

That’s about the most long winded, pompous and dramatic speech I’ve read in regards to the MD 11


That's all you've ever done with the MD-11, isn't it? Read.

An expert reader, then. The industry needs more experts who learned everything they know by reading about it on the internet.

Max Q wrote:
I started this topic with a view to soliciting opinions on what could have made this aircraft safer, blah, blah, blah


You started the topic biased, and your comments are based on little more than an opinion you've formed, without a leg to stand upon on the subject. You know squat about the design, it's handling, training, or any other aspect, and thus far, nearly everything you've had to say about it has been wrong. That you keep pushing deeper into wrong to defend the incorrect speaks volumes about where you stand on the matter. Otherwise, it would have been dropped by now. You don't know what you're talking about, but you're damn proud to do it anyway.

Yes, a civil discourse is more of a slap down in your case, because rather than admit it, you're quite dogged in your desire to drive home a hollow point about which you know nothing and have no experience. You're very quick to dismiss those who do know something about the design, or are type rated, who have experience, and training in the type, in favor of what you think you know from reading snippets off the internet.

You're about 15' deep and still digging deeper. How deep will this hole go?




None of that long, bizarre rant changes anything



The poor accident and incident record of the MD11 speaks for itself, blaming the Pilots involved is counterproductive, unfair and doesn’t address the problems with its design



As an observation, the best pilots I’ve worked with over the years have always been the ones who listened to others, solicited input, didn’t feel a need to repeatedly tell you how experienced they were or how many types they’d flown, the
quality of their airmanship was and is what counts
The best contribution to safety is a competent Pilot.
 
BravoOne
Posts: 2988
Joined: Fri Apr 12, 2013 2:27 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 2:39 am

Yea I like VCR from the Feds MD11 at NRT where the Captain says "ridem cowboy" speaks volumes about where their mind was just before pranging it on the runway. Max you are so far out of line that you are damaging your reputation.
 
426Shadow
Posts: 86
Joined: Tue Sep 11, 2007 8:13 am

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 3:07 am

Boy this topic is ripe for a locking isn't it?
Do it on three, One.....THREEEEEEE! Just got the nuts hangin out.
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 4:06 am

Hmmm, could this thread could have a hard landing, but still have a porpoise.
https://www.airliners.net/photo/FedEx-F ... -F/1052108
https://flightaware.com/photos/view/408 ... e/fullsize

"Large nose-down elevator input at the first touchdown...PF‘s large elevator input in an attempt to control the airplane without thrust during the second bounce.." might work in other frames, but... https://www.baaa-acro.com/crash/crash-m ... o-2-killed

Was there an AD on the fuse pin?
"It is somewhat likely that, if the fuse pin in the MLG support structure had failed and the MLG had been separated in the overload condition in which the vertical load is the primary component, the damage to the fuel tanks would have been reduced to prevent the fire from developing rapidly. It is probable that the fuse pin did not fail because the failure mode was not assumed under an overload condition in which the vertical load is the primary component due to the interpretation of the requirement at the time of type certification for the MD-11 series airplanes. "
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 4:45 am

The PF was the FO, who had 879 hours on type, out of 5248 hours total. The PM was the PIC, who had 3648 hours on type, out of 8132 total. FX080 was not their first rodeo.
 
Max Q
Topic Author
Posts: 6968
Joined: Wed May 09, 2001 12:40 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 4:45 am

It’s interesting when you look at what should be survivable


When British Airways made a very hard landing with a 777 after losing power in both engines all passengers survived, the landing gear was pushed up through the wing but the wing itself remained attached


Good, redundant and forgiving design allowed everyone to walk away


Unlike the MD11
The best contribution to safety is a competent Pilot.
 
acjbbj
Posts: 132
Joined: Sat Mar 17, 2018 7:06 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 4:54 am

Guys. Please don't turn this into an MD-11 bashing thread.
R.I.P.

Douglas Aircraft Company

1921 - 2006

You will be missed.
 
747Whale
Posts: 271
Joined: Fri Dec 07, 2018 7:41 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 7:23 am

Max Q wrote:
As an observation, the best pilots I’ve worked with over the years have always been the ones who listened to others, solicited input, didn’t feel a need to repeatedly tell you how experienced they were or how many types they’d flown, the
quality of their airmanship was and is what counts


Well, you know what? At least they'd flown the damn airplane. Keep digging.

I'm out.
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 7:41 am

Dupe............
Last edited by stratclub on Sat Dec 15, 2018 8:05 am, edited 1 time in total.
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 7:43 am

WPvsMW wrote:
Hmmm, could this thread could have a hard landing, but still have a porpoise.
https://www.airliners.net/photo/FedEx-F ... -F/1052108
https://flightaware.com/photos/view/408 ... e/fullsize

"Large nose-down elevator input at the first touchdown...PF‘s large elevator input in an attempt to control the airplane without thrust during the second bounce.." might work in other frames, but... https://www.baaa-acro.com/crash/crash-m ... o-2-killed

Was there an AD on the fuse pin?
"It is somewhat likely that, if the fuse pin in the MLG support structure had failed and the MLG had been separated in the overload condition in which the vertical load is the primary component, the damage to the fuel tanks would have been reduced to prevent the fire from developing rapidly. It is probable that the fuse pin did not fail because the failure mode was not assumed under an overload condition in which the vertical load is the primary component due to the interpretation of the requirement at the time of type certification for the MD-11 series airplanes. "

What fuse pin are you reffering to? Do you mean the designed in controlled shear out for the landing gear that would shear it off if it hit an immovable object.? IDK how you could design the gear so that it would not damage the fuel tank if the gear was forced straight up. Do you have an AD note or Service Bulletin number for this fuse pin you referred to?
Last edited by stratclub on Sat Dec 15, 2018 8:03 am, edited 2 times in total.
 
strfyr51
Posts: 3225
Joined: Tue Apr 10, 2012 5:04 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 7:46 am

Max Q wrote:
This aircraft did not have the most impressive record with respect to accidents and incidents


On several occasions a hard landing led to a complete failure of the main wing spar
causing the aircraft to turn over with disastrous results



But the DC 10, for all of its issues didn’t
have this problem


I think a bigger wing could have helped but I believe the main problem with The MD11
was it’s under sized horizontal stabilizer,
two thirds the size of its predecessor in an attempt to reduce drag


As a result, pitch control authority was reduced and approaches had to be flown at significantly higher airspeeds making for a far less forgiving aircraft in the flare, especially at the typical high landing weights of pure freighter versions.


I know an artificial stability system was added to assist in pitch control but I don’t know if that helped very much



What if MD had just left the horizontal stabilizer alone ? Using the same size as
the DC10 would have helped significantly, perhaps eliminated this problem



As a comparison, the vertical and horizontal stabilizer size was unchanged by
Boeing when transitioning from the 747
Classic to the 744, no such problems were encountered

possbly better weight and Balance
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 8:20 am

stratclub wrote:
What fuse pin are you reffering to? Do you mean the designed in controlled shear out for the landing gear that would shear it off if it hit an immovable object.? IDK how you could design the gear so that it would not damage the fuel tank if the gear was forced straight up. Do you have an AD note or Service Bulletin number for this fuse pin you referred to?


See the investigation report. https://www.baaa-acro.com/sites/default ... N526FE.pdf

The inference I draw is that the fuse pin was designed to shear only by X-axis loads, not Y-axis loads, and should have been designed to shear in X-axis and/or Y-axis loads (like the fuse pins in the B777).

Similar event, on LH Cargo. 4.4 Gs on the second porpoise touchdown broke the entire fuselage aft of the wing. https://www.1001crash.com/index-page-de ... h-278.html
 
Max Q
Topic Author
Posts: 6968
Joined: Wed May 09, 2001 12:40 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 8:52 am

747Whale wrote:
Max Q wrote:
As an observation, the best pilots I’ve worked with over the years have always been the ones who listened to others, solicited input, didn’t feel a need to repeatedly tell you how experienced they were or how many types they’d flown, the
quality of their airmanship was and is what counts


Well, you know what? At least they'd flown the damn airplane. Keep digging.

I'm out.




We’ve flown various and sundry types over the years, each has its own characteristics
There is nothing like flying the specific type
and gaining experience on it.



However you don’t need to have flown an MD11 to educate yourself on its poor accident history, to imply that’s necessary is ridiculous, all you have to do is read the numerous NTSB reports
The best contribution to safety is a competent Pilot.
 
Max Q
Topic Author
Posts: 6968
Joined: Wed May 09, 2001 12:40 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 9:00 am

strfyr51 wrote:
Max Q wrote:
This aircraft did not have the most impressive record with respect to accidents and incidents


On several occasions a hard landing led to a complete failure of the main wing spar
causing the aircraft to turn over with disastrous results



But the DC 10, for all of its issues didn’t
have this problem


I think a bigger wing could have helped but I believe the main problem with The MD11
was it’s under sized horizontal stabilizer,
two thirds the size of its predecessor in an attempt to reduce drag


As a result, pitch control authority was reduced and approaches had to be flown at significantly higher airspeeds making for a far less forgiving aircraft in the flare, especially at the typical high landing weights of pure freighter versions.


I know an artificial stability system was added to assist in pitch control but I don’t know if that helped very much



What if MD had just left the horizontal stabilizer alone ? Using the same size as
the DC10 would have helped significantly, perhaps eliminated this problem



As a comparison, the vertical and horizontal stabilizer size was unchanged by
Boeing when transitioning from the 747
Classic to the 744, no such problems were encountered

possbly better weight and Balance



Agree, still think it would have been
a far more forgiving aircraft if MD had used
the same horizontal stabilizer as the DC10


Reducing its size so radically may have helped with drag but in order to give the pilots adequate pitch authority the approach needed to be flown at a far higher airspeed which is a big part of its problems


A larger wing, incorporation of DLC as tested on the DC10 and other refinements all could have helped perhaps



Interesting to ponder what would have made a difference
The best contribution to safety is a competent Pilot.
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 9:46 am

WPvsMW wrote:
stratclub wrote:
What fuse pin are you reffering to? Do you mean the designed in controlled shear out for the landing gear that would shear it off if it hit an immovable object.? IDK how you could design the gear so that it would not damage the fuel tank if the gear was forced straight up. Do you have an AD note or Service Bulletin number for this fuse pin you referred to?


See the investigation report. https://www.baaa-acro.com/sites/default ... N526FE.pdf

The inference I draw is that the fuse pin was designed to shear only by X-axis loads, not Y-axis loads, and should have been designed to shear in X-axis and/or Y-axis loads (like the fuse pins in the B777).

Similar event, on LH Cargo. 4.4 Gs on the second porpoise touchdown broke the entire fuselage aft of the wing. https://www.1001crash.com/index-page-de ... h-278.html

Thank you. Do you have any graphics of the fuse pin in question? I'll study the report and get back to you. If you have the SB or AD that applies, there will be some graphics included. I'm not familiar with the MD11's aircrafts design so my opinion is just that. An uninformed opinion.
 
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Horstroad
Posts: 473
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Re: What would have made the MD11 safer?

Sat Dec 15, 2018 11:28 am

Max Q wrote:
The poor accident and incident record of the MD11 speaks for itself


Actually it does not. As described above many accidents were not due to design issues but "mishandling". I can't add anything to what 747Whale said in that regard.

I have been working on the MD11 for 7 and a half years as a technician. I'm not a pilot but I have been in the jump seat quite a few times. I have seen pilots really working her down in RUH on a hot afternoon. The MD11 might be more demanding and less forgiving than other types. But this doesn't make it less save. If you operate any aircraft outside its designed envelope you're going to have a bad day. The envelope on the MD11 might be tighter but proper training and respect for the aircraft can account for that.

From my experience you either love the MD11 or you don't know her. And I mean really know her, not just read about her or occasionally work on her. It is a special aircraft with a special design and special characteristics. This is just the good old A vs B argument except MD is out of favor on both sides. We don't like what we don't know and/or understand.
 
ExpatVet
Posts: 45
Joined: Mon Sep 03, 2018 4:35 am

Re: What would have made the MD11 safer?

Sat Dec 15, 2018 11:47 am

From a passenger perspective, I loved the MD-11. Comfy, quiet, just an all round nice experience.

(I can imagine that daytime flying in KSA must have been a pain!)
L101, 733/4/5/8, 741/2/3 (never managed 744!), MD 80/2/3/8/90, MD11, DHC8/3/Q4, E170, E195, 757, 77W, 763/4, Travel Air 2000. A300/310, A319/320/321, A333, probably a few others I forget. Passenger, not pilot, alas! BUD based.
 
Max Q
Topic Author
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Re: What would have made the MD11 safer?

Sat Dec 15, 2018 1:05 pm

Horstroad wrote:
Max Q wrote:
The poor accident and incident record of the MD11 speaks for itself


Actually it does not. As described above many accidents were not due to design issues but "mishandling". I can't add anything to what 747Whale said in that regard.

I have been working on the MD11 for 7 and a half years as a technician. I'm not a pilot but I have been in the jump seat quite a few times. I have seen pilots really working her down in RUH on a hot afternoon. The MD11 might be more demanding and less forgiving than other types. But this doesn't make it less save. If you operate any aircraft outside its designed envelope you're going to have a bad day. The envelope on the MD11 might be tighter but proper training and respect for the aircraft can account for that.

From my experience you either love the MD11 or you don't know her. And I mean really know her, not just read about her or occasionally work on her. It is a special aircraft with a special design and special characteristics. This is just the good old A vs B argument except MD is out of favor on both sides. We don't like what we don't know and/or understand.




Apples and oranges



The accident record of the MD11 does speak for itself



You can’t say ‘it’s less forgiving and more demanding’ but is no less safe



That makes no sense, as is born out by the record



Top notch carriers with experienced flight crews have suffered catastrophic accidents
with this aircraft



Blaming it on the pilots is unfair and unrealistic



Even the best pilots have bad days, in a Boeing or Airbus a less than stellar performance or misjudgement may bend something but probably won’t kill you


More importantly those designs are far more forgiving and you’re less likely to have a problem in the first place
The best contribution to safety is a competent Pilot.
 
stratclub
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Re: What would have made the MD11 safer?

Sat Dec 15, 2018 9:44 pm

stratclub wrote:
WPvsMW wrote:
stratclub wrote:
What fuse pin are you reffering to? Do you mean the designed in controlled shear out for the landing gear that would shear it off if it hit an immovable object.? IDK how you could design the gear so that it would not damage the fuel tank if the gear was forced straight up. Do you have an AD note or Service Bulletin number for this fuse pin you referred to?


See the investigation report. https://www.baaa-acro.com/sites/default ... N526FE.pdf

The inference I draw is that the fuse pin was designed to shear only by X-axis loads, not Y-axis loads, and should have been designed to shear in X-axis and/or Y-axis loads (like the fuse pins in the B777).

Similar event, on LH Cargo. 4.4 Gs on the second porpoise touchdown broke the entire fuselage aft of the wing. https://www.1001crash.com/index-page-de ... h-278.html

Thank you. Do you have any graphics of the fuse pin in question? I'll study the report and get back to you. If you have the SB or AD that applies, there will be some graphics included. I'm not familiar with the MD11's aircrafts design so my opinion is just that. An uninformed opinion.

Very informative. Thanks again. Fuse pin = Controlled shear out mounting Bolt. Back in the day, we called fuse pins bottle bolts. From what I read, it sure looks like what failed was not the gear trunnion mount(s) not breaking away as the gear was still attached to the wing. If I read it right, what failed was that the side brace pillow block (side brace trunnion) tore the structure out of the rear spar which lead to the ultimate failure to the wing. (Not 100% sure on this)

Sure reminds me of the cargo door fiasco or the leading edge devices that are not locked in the extend position if hydraulic power is lost. Even the 727 had ratchet check valves in the leading edges that would not release until hydraulic pressure was applied to the retract side of the actuators. If you loose hydraulics in a 727 and if the leading edges are extended, they will stay that way.

In a failure mode, if something fails, it should fail in a way that it does not effect the survivability of the aircraft. Apparently, MD did not subscribe to that philosophy when they designed the DC 10 and MD 11. IIRC, MD fought the FAA tooth and nail because they didn't want to fix a very real design flaw in the design of the leading edge devices on the DC 10 and perhaps on the MD 11.

AAL flight 191 might have been survivable if the leading edge devices on the left wing hadn't collapsed sending the aircraft into a death roll to the left when the left engine departed the aircraft.

Poor airmanship had a lot to do with various incidents, but MD's design philosophy certainly made the outcome worse in several of those incidents. A blunder by the flight crew in no way should be compounded by poor design.
 
KCharlie
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 6:21 am

Yikes, 168 knots at max landing weight? Are there any other airplanes that high?

Now days, there's no way an airline would ever buy a new airplane with such a high approach speed.
 
WPvsMW
Posts: 1483
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:52 am

stratclub wrote:
If you have the SB or AD that applies, there will be some graphics included.


https://www.faa.gov/regulations_policie ... h/?q=MD-11
The latest AD on the MD-11 is 2018-10-21 ... and they go back to 1991.
I didn't see anything in the AD titles about fuse bolts or bottle bolts. There's one on corrosion on the MLG trunions, and one on mfg defects in the NLG drag link. Quite few NLG collapses in the MD-11's history.
 
stratclub
Posts: 701
Joined: Fri Jan 05, 2018 10:38 pm

Re: What would have made the MD11 safer?

Sun Dec 16, 2018 10:06 am

That is what I thought. After all the aircraft did meet the design criteria when the FAA signed off on it during initial certification. I did see some recommendations from the FAA in regards to further study on structural loads on the landing gear when the load is of a vertical nature. This recommendation was not just in regards to the DC 10, but all heavy aircraft. The recommendation is in the accident report.

As for as the fuse pins go the best I can tell is that they were not an issue on this incident. The investigation seemed to say that the main gear attach points to the rear spar did not fail structurally. From the report, the failure seemed to be that the side strut pillow block tore out a section of the rear spar which caused a fuel leak and catastrophic failure of the wing.

It does mean that if the main gear fuse pins failed at a lower ultimate load that the side strut pillow block might not have failed the way it did or perhaps it could mean that the actual design flaw was in how the side strut pillow block attached to the rear spar.
 
WPvsMW
Posts: 1483
Joined: Thu Mar 23, 2017 7:30 pm

Re: What would have made the MD11 safer?

Sun Dec 16, 2018 10:17 am

Is is curious that no ADs were triggered by FX080 at NRT, even though JTSB suggested they were needed.
 
747Whale
Posts: 271
Joined: Fri Dec 07, 2018 7:41 pm

Re: What would have made the MD11 safer?

Sun Dec 16, 2018 1:37 pm

KCharlie wrote:
Yikes, 168 knots at max landing weight? Are there any other airplanes that high?

Now days, there's no way an airline would ever buy a new airplane with such a high approach speed.


You've never flown a 747, have you?
 
BravoOne
Posts: 2988
Joined: Fri Apr 12, 2013 2:27 pm

Re: What would have made the MD11 safer?

Sun Dec 16, 2018 1:58 pm

Max Q wrote:
strfyr51 wrote:
Max Q wrote:
This aircraft did not have the most impressive record with respect to accidents and incidents


On several occasions a hard landing led to a complete failure of the main wing spar
causing the aircraft to turn over with disastrous results



But the DC 10, for all of its issues didn’t
have this problem


I think a bigger wing could have helped but I believe the main problem with The MD11
was it’s under sized horizontal stabilizer,
two thirds the size of its predecessor in an attempt to reduce drag


As a result, pitch control authority was reduced and approaches had to be flown at significantly higher airspeeds making for a far less forgiving aircraft in the flare, especially at the typical high landing weights of pure freighter versions.


I know an artificial stability system was added to assist in pitch control but I don’t know if that helped very much



What if MD had just left the horizontal stabilizer alone ? Using the same size as
the DC10 would have helped significantly, perhaps eliminated this problem

Max you think that all you want but it sort falls under old wives tales. Simply not the case.

As a comparison, the vertical and horizontal stabilizer size was unchanged by
Boeing when transitioning from the 747
Classic to the 744, no such problems were encountered

possbly better weight and Balance



Agree, still think it would have been
a far more forgiving aircraft if MD had used
the same horizontal stabilizer as the DC10


Reducing its size so radically may have helped with drag but in order to give the pilots adequate pitch authority the approach needed to be flown at a far higher airspeed which is a big part of its problems


A larger wing, incorporation of DLC as tested on the DC10 and other refinements all could have helped perhaps



Interesting to ponder what would have made a difference
 
CosmicCruiser
Posts: 2272
Joined: Tue Feb 22, 2005 3:01 am

Re: What would have made the MD11 safer?

Sun Dec 16, 2018 2:15 pm

I say every time I see another MD-11 post I WILL NOT comment but here I ago...again. I will say I did not go back and read all these posts so forgive any repeats. The ONE biggest problem that repeats in both Fedex crashes was side loads not just hard landings. Like 747whale said I had my hard ldgs too. My most memorable was landing in DEL on the short runway after a rain, not grooved, with flaps 50. As for the NRT crash, until my last day there they never knew why they had a hard landing. At least I never heard. They were stable but they did have a very gusty wind. For whatever reason the bottom dropped out. The BIG mistake was after the bounce they unloaded the elevator and the nose dropped and they hit left side first. There were procedural changes after that for sure. It was to ensure that you would NOT try to salvage a hard landing. Any hard landing was to be followed by max power, pitch 7ºNU and even if the mains hit the runway and go around was to follow. We saw this in every sim afterwards. 7º NU both visually out the window and inside using the PFD.
The EWR crash was self induced. For some reason the Capt. thought they didn't have enough stop dist. and even though initially stable decided to "stick it on the end". This resulted in the hard landing and when it came down there was a side load on the right main. The MD-10 had similar accidents. At least one due to less than proficient pilot making a x-wind landing. After NRT they also drilled no crab in x-wind landings in the sim.
 
747Whale
Posts: 271
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 3:34 pm

Boeing has changed the guidance regarding crosswind landings, and whereas there used to be strict admonition not to land with any sideload, Boeing now asserts that it's far more important to be stable and not bounce than worry about kicking it out to get the long axis oriented with the runway. Concern about side load is now backseat to concern about a stable landing, with the inference that it's possible in the last few feet of the approach to destabilize by kicking it out.
 
CosmicCruiser
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 4:19 pm

We never kicked it out at the last minute. We entered the slip at about 200' agl and therefore would be well stable by touchdown. In all the accidents the design side load was far exceeded. And at least until the day I walked out the door nothing had changed. I'll check with a MD buddy and see if anything has changed. Of course with the addition of 777s that concern is negligible. I can't believe that Fedex would give the pilots latitude to make that call as to how much is ok. They were hard fast on that for yrs.
 
BravoOne
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 4:46 pm

So here is a question. Why do you suppose FedEx had so many incidents (tail strikes), as opposed to say UPS/AA/DAL and various other operators? I know the FedEx pilots are cut from the same cloth as the others, but they seemed to have a greater amount of misfortune than some, not discounting the greater number of MD11's they operate. The only difference I can imagine is perhaps training and checking?
 
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AirlineCritic
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 6:44 pm

WPvsMW wrote:


Thanks for posting this, I had not seen this before. They do have some tough conclusions.
 
WPvsMW
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 7:09 pm

The MD-11 had severe tail strikes that the pilots didn't realize happened. More such tail strikes than others, it seems.
http://avherald.com/h?article=45cb7632

Tail strike after one porpoise at MEM... go around... clear WX, 10 knot c/w. The pilots executed the prescribed "fix" .. 7 degrees NU and power after 1 porpoise.
https://www.fss.aero/accident-reports/d ... -19-US.pdf
I suspect a W&B error... like the tail strike at PDX (another one the pilots didn't know happened during landing).
https://aviation-safety.net/database/re ... 19981111-2
Better to have a tail strike than a broken bird.

Inference: There are probably more tail strikes that were publicly reported if pilots were unaware of the strikes. MX fixes minor stuff all the time.

There are many more... and commentary. https://www.forbes.com/sites/tedreed/20 ... 1b8cb240d5
 
BravoOne
Posts: 2988
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 7:38 pm

426Shadow wrote:
Boy this topic is ripe for a locking isn't it?


Why would you want to see this locked??
 
BravoOne
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 7:53 pm

WPvsMW wrote:
The MD-11 had severe tail strikes that the pilots didn't realize happened. More such tail strikes than others, it seems.
http://avherald.com/h?article=45cb7632

Tail strike after one porpoise at MEM... go around... clear WX, 10 knot c/w. The pilots executed the prescribed "fix" .. 7 degrees NU and power after 1 porpoise.
https://www.fss.aero/accident-reports/d ... -19-US.pdf
I suspect a W&B error... like the tail strike at PDX (another one the pilots didn't know happened during landing).
https://aviation-safety.net/database/re ... 19981111-2
Better to have a tail strike than a broken bird.

Inference: There are probably more tail strikes that were publicly reported if pilots were unaware of the strikes. MX fixes minor stuff all the time.

There are many more... and commentary. https://www.forbes.com/sites/tedreed/20 ... 1b8cb240d5


Generally speaking tail strikes are not reported to the public, unless there is significant subsequent damage. None the less, it's hard to imagine that they would go unnoticed by the crew. Perhaps the fact that they were freighters and not pax aircraft would explain this. Get a tail strike on a 727 and the flight attendants would ring the bell before the wheels were up, and gear doors closed. You can also feel It in the controls.

When the MD11 was new FedEx, DAL and AA freely exchanged information regarding their experiences with the airplane. FedEx was having issues from the get go. The rest is history.
 
CosmicCruiser
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:23 pm

WPvsMW wrote:

Tail strike after one porpoise at MEM... go around... clear WX, 10 knot c/w. The pilots executed the prescribed "fix" .. 7 degrees NU and power after 1 porpoise.
https://www.fss.aero/accident-reports/d ... -19-US.pdf
I suspect a W&B error... like the tail strike at PDX (another one the pilots didn't know happened during landing).
https://aviation-safety.net/database/re ... 19981111-2
Better to have a tail strike than a broken bird.


Reread the article. When the capt. initiated the go around the pitch went 12ºNU and stayed there. That's definitely tailstrike territory.
 
CosmicCruiser
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:26 pm

FedEx was having issues from the get go. The rest is history.

I waited about a yr before going to the -11. In that year the software load in LSAS was causing some pitch ups on landing. When I heard guys talk about it I decided to stay in the -10. By the time I went over it wasn't an issue I ever encountered.
 
WPvsMW
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:48 pm

CC, you're correct, 12ºNU at MEM. The 7ºNU was in a different report.
 
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Faro
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:49 pm

zeke wrote:
BravoOne wrote:
When you poor pilot technique tends to bring the worst design flaws. None of these hull losses would havee occurred had the pilots flown the airplane according to the procedures set forth by MD.


It is not poor pilot techniques, it is a poor design. Have a look at the carriers that have some of these hull losses, very experienced pilots on types, and a number of them from top first world airlines.

First, the MD-11 is essentially a stretched DC-10, with winglets, a 2-crew cockpit (one fewer than on the DC-10), and a few other nips and tucks. Significantly, the designers increased the operating weight and the length of the aircraft, without re-engineering the wing and rudder. As a result, the aircraft has rather sluggish roll and yaw responses to control input at low speeds, i.e., on short finals and during the landing flare.

The second significant factor that affects the MD-11s landing performance is speed. In order to compensate for the MD-11’s higher operating weight and reduced rudder authority, its approach speeds can be substantially higher than other comparable commercial jets. This is due to the higher Vmca of the MD-11. The term refers to the minimum airspeed at which an airborne multiengine aircraft is controllable with one engine inoperative (the MD-11 has three engines). For example, the approach speed (Vapp) for the MD-11 at maximum landing weight (213.8 tons) is around 168 knots, give or take 1-2 knots. This is increased further – by up to 20 knots – if allowances for high winds or gusts are factored into the landing calculations. As a consequence, the sink rate on a heavy approach is usually a few hundred feet per minute higher than on most other transport-category aircraft.

The third factor is the center-gear of the main landing gear. Quite unlike the center-body gear on the B747, which is quite forgiving, the center-line fuselage gear on the MD-11 is primarily designed to support the stretched airplane’s increased ramp weight. Its position at the fuselage center, slightly aft of the main gear, has a significant effect on the landing characteristics of the aircraft. For this reason, it is imperative that the pilot does not continue to flare the aircraft when the radio altimeter callout reaches 10 feet. There should be no continued flare even if the aircraft is not in the desired landing altitude. If the pilot continues to apply back pressure on the control column past this 10 foot radio altitude point, the flare has the effect of driving the center gear onto the runway, which in turn creates a large “up” force on the tail section of the aircraft – which in turn drives the nose gear onto the tarmac and creates a bounce.

Fourth, because of the airplane’s small horizontal stabilizer, a computerized longitudinal stability augmentation system (LSAS) was installed to improve handling qualities (and also the airplane’s shortfall in range). But this system does not operate when the autopilot must be disconnected and the aircraft hand-flown to touchdown.

Please chime in if younthis this is inaccurate or unfair. The aircraft also has a hull loss rate per 100,000 landings about 5-10 times higher than other airliners.




But then to my mind, this is a regulatory failure, not necessarily one of design. The FAA and other national regulatory bodies gave it the thumbs up. Why did they do this and not mandate changes to the initial design? And what has changed in their certification practices since then?


Faro
Last edited by Faro on Sun Dec 16, 2018 8:51 pm, edited 1 time in total.
The chalice not my son
 
WPvsMW
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Re: What would have made the MD11 safer?

Sun Dec 16, 2018 8:51 pm

Re: regulatory failure. After FX080 at NRT, no AD even after JTSB recommendation.

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