Lufthansa cargo plane crash
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I said it a million times already:
The MD11 is not tricky in the real sense of the word. It just needs good pilots who can deliver stable final approaches.
The speed/drag curve is climbing sharply behind Va and one should never get below that reference. But this should be trivial for a professional. That it is not, originates in the new training methods and shortcuts. Many pilots are routed through aircraft that no longer really need pitch and power discipline. They are told that if in trouble, to let go of the stick/yoke and most certainly not to interfere with the holy thrust levers, automation should take care of it! It takes away the pilots' awareness of impending speed loss, of what a increasing attitude may warn of, that chasing the flight director may please a TRE in the sim and all the sops, but is detrimental to stable short finals if you weren't established throughout the approach beforehand.
What surprises me is not the fact that we might be discussing such accidents, but the lack of honest awareness of why they happen.
The MD11 is not tricky in the real sense of the word. It just needs good pilots who can deliver stable final approaches.
The speed/drag curve is climbing sharply behind Va and one should never get below that reference. But this should be trivial for a professional. That it is not, originates in the new training methods and shortcuts. Many pilots are routed through aircraft that no longer really need pitch and power discipline. They are told that if in trouble, to let go of the stick/yoke and most certainly not to interfere with the holy thrust levers, automation should take care of it! It takes away the pilots' awareness of impending speed loss, of what a increasing attitude may warn of, that chasing the flight director may please a TRE in the sim and all the sops, but is detrimental to stable short finals if you weren't established throughout the approach beforehand.
What surprises me is not the fact that we might be discussing such accidents, but the lack of honest awareness of why they happen.
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Not a professional input but just a simple observation - and a lesson to all our "expert" PPRuNe air accident experts: There was no emergency declared nor an on-board fire prior to the accident!
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Heavy Jet unseasoned FOs
I noticed LH cargo carries a lot of rather junior looking First Officers.Is it for some their first type rating?
For normal flying carying inexperienced FOs as handling pilots shouldn't be an issue.When the maneoure hits the turbo fan!!!!!....these heavy jets become a handful even for the most experienced F.O.s I saw one video IN U tube of an Alitalia MD11 landing in Hong Kong...what looked like a normal stabilized approach suddenly ...like a viper bite..snapped at the co-pilot's hands (and he seemed experienced) and the juggernaut snapped into a dangerous attitude...much to the Captain's chagrin who was left barking like a mad dog!
I have witnessed both LH Cargo and Swiss in Nairobi doing some pretty unstabilizing (to the onlookers eyes
) tango manoeuvres at below 300 feet!I haven't flown these monstrous tri-jets except on simulator (Tristar and DC-10 63).I have noticed in sim that they tend to just want to drop if you let them slide behind the min drag speed point...and without a generous pitch and thrust...you would be doomed
For normal flying carying inexperienced FOs as handling pilots shouldn't be an issue.When the maneoure hits the turbo fan!!!!!....these heavy jets become a handful even for the most experienced F.O.s I saw one video IN U tube of an Alitalia MD11 landing in Hong Kong...what looked like a normal stabilized approach suddenly ...like a viper bite..snapped at the co-pilot's hands (and he seemed experienced) and the juggernaut snapped into a dangerous attitude...much to the Captain's chagrin who was left barking like a mad dog!
I have witnessed both LH Cargo and Swiss in Nairobi doing some pretty unstabilizing (to the onlookers eyes
) tango manoeuvres at below 300 feet!I haven't flown these monstrous tri-jets except on simulator (Tristar and DC-10 63).I have noticed in sim that they tend to just want to drop if you let them slide behind the min drag speed point...and without a generous pitch and thrust...you would be doomed
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LH747 stall after take off
That was the first 747 crash.It was in Nairobi (1973-75?).Leading edge flaps were forgotten to be deployed..due to a taxi procedure to isolate some switch.Since then the flight control surface position indicators were designed and installed in all Boeings of that generation...which trickled down to the 732!
)
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That was the first 747 crash.It was in Nairobi (1973-75?)
Was it also because of some under-qualified F/O? It certainly wasn't one of your "monstrous tri-jets" (you do seem to mix up your types a little bit).
BTW
I haven't flown these monstrous tri-jets except on simulator (Tristar and DC-10 63)
?There's somebody turning in his grave
Sqwak7700;
Re, "I can't believe that 10ft difference in flare height is enough to total an airframe. Most jets only give you a firm landing if you flare a bit late. And if you carry a bit extra speed crossing the threshold, many will give you a greaser. "
Trying to clarify here...I don't think it was a "10ft difference in flare height" that was "enough to total an airframe". From the Saudi Report:
4. The Captain attempted to take control of the aircraft without alerting the First Officer resulting in both flight crews acting simultaneously on the control column.
5. During the first bounce, the Captain made an inappropriate, large nose-down column input that resulted in the second bounce and a hard landing in a flat pitch attitude.
6. The flight crew responded to the bounces by using exaggerated control inputs.
To me this sounds more like PIO than it does a late flare. As others have pointed out, the screenshots from the airport security camera showing the initial touchdown, bounce, nose-high then flat touchdown certainly look like Narita.
I haven't flown the type but from what those who have have observed the airplane may require stricter control of pitch and power but is otherwise normal. A disciplined approach to pitch and power has been mentioned before regarding this design including bounced-landing training. Messing with pitch control after a bounce is, I think, asking for trouble in any airplane, the SOP generally being a go-around but surprise and "focus on the mission" when things are happening rapidly....etc
Re, "I can't believe that 10ft difference in flare height is enough to total an airframe. Most jets only give you a firm landing if you flare a bit late. And if you carry a bit extra speed crossing the threshold, many will give you a greaser. "
Trying to clarify here...I don't think it was a "10ft difference in flare height" that was "enough to total an airframe". From the Saudi Report:
4. The Captain attempted to take control of the aircraft without alerting the First Officer resulting in both flight crews acting simultaneously on the control column.
5. During the first bounce, the Captain made an inappropriate, large nose-down column input that resulted in the second bounce and a hard landing in a flat pitch attitude.
6. The flight crew responded to the bounces by using exaggerated control inputs.
To me this sounds more like PIO than it does a late flare. As others have pointed out, the screenshots from the airport security camera showing the initial touchdown, bounce, nose-high then flat touchdown certainly look like Narita.
I haven't flown the type but from what those who have have observed the airplane may require stricter control of pitch and power but is otherwise normal. A disciplined approach to pitch and power has been mentioned before regarding this design including bounced-landing training. Messing with pitch control after a bounce is, I think, asking for trouble in any airplane, the SOP generally being a go-around but surprise and "focus on the mission" when things are happening rapidly....etc
My point, and what I'm wondering is, if the (instant) decision is to say on the runway and not go-around, and if the control column inputs remain neutral, will the MD11 still behave the same way in pitch. In other words, is the airplane pitch-unstable in a bounce or is the instability a result of control inputs, small or large? If one freezes the control column and waits for the next touchdown, will the airplane behave as we have seen or is this sufficient to stabilize the landing such that its "normal"? Bear in mind the crew did not recognize that the aircraft had bounced.
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golfyankeesierra
Hey...Mr.Perfect...haven't you made a syntax error in your life?You are only publicising your childish mentality by writing what you wrote.
I stand corrected..the DC-63 never got built, but there were plans for it with RR engines and B.A. had expressed interest.I meant DC-10 series 10,30 and 40...IF THAT WILL SATISFY your bloody mindedness.Yes we do know that DC-8 had a series 63, and perhaps with an engine transfer on the DC-10 you would be the ace test pilot to fly it...and use the other spare engine as its APU stuck aptly...in YOUR tail!
I stand corrected..the DC-63 never got built, but there were plans for it with RR engines and B.A. had expressed interest.I meant DC-10 series 10,30 and 40...IF THAT WILL SATISFY your bloody mindedness.Yes we do know that DC-8 had a series 63, and perhaps with an engine transfer on the DC-10 you would be the ace test pilot to fly it...and use the other spare engine as its APU stuck aptly...in YOUR tail!
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MD 11 history of accidents by virtue of design fault?
The MD-11 was designed with a smaller horizontal stabilizer than other airliners. That, plus the shifting of its center of gravity further aft, all to reduce drag and thus fuel burn, causes it to be unusually light on the controls. That design, known as “relaxed stability,” is common to fighter planes but is not normally found in the pitch axis of a civilian airliner. It makes it more likely that the pilot will overcontrol during an upset recovery.
1994, November 4. A Fed Ex MD-11 freighter made a hard landing, and a tail strike at the Anchorage, Alaska airport. After selecting 50 degrees of flaps the first officer, who was flying the plane, was not able to stabilize the approach in the pitch mode. The attitude of the plane varied approximately 2 degrees with corresponding elevator position changes. The captain, because of the high sink rate, grabbed the yoke and pulled back. The plane landed hard, bounced, and oscillated at least three times, reaching a maximum pitch up attitude of 12.3 degrees. The tail struck the runway during the oscillations. This was also the plane that crashed at Newark in 1997.
1996, May 16. A Fed Ex MD-11 freighter encountered wake turbulence from a preceding 747 as it was landing at the Anchorage, Alaska airport and suffered substantial damage. When the plane entered a high sink rate, the captain tried to go-around but the lower aft fuselage hit the runway and bounced. The captain discontinued the go-around and the plane bounced two more times, causing substantial damage to the aft pressure bulkhead.
Prior to this accident, Fed Ex did not have formal tailstrike awareness training for its MD-11 pilots. After this accident, however, Fed Ex developed a tail strike awareness training program that included bounced landing recovery in its simulator training. That program limited pitch attitude to 7-1/2 deg for recovery from a bounced landing.
1997, June. Thirteen people were seriously injured when a Japan Airlines MD-11 experienced severe pitch oscillations. One passenger went into a coma and died, 20 months later.
The pilot attempted manual recovery when the autopilot failed to detect the plane was flying too fast after an encounter with wind shear. The pilot’s repeated attempts to stabilize the altitude caused the severe oscillations that injured passengers and crew. The autopilot was blamed for the accident because it contained a programming design defect that commanded it to respond to average velocity calculations instead of actual speeds.
1997, July 31. A Fed Ex MD-11 bounced on landing at Newark airport and then flipped upside down off runway 22 R. The two pilots and three passengers managed to escape before the plane was destroyed by fire. The investigation is focusing on the failure of the right main gear, which allowed the right engine and wing to dig into the ground, flipping the plane over.
There is now some question about the structural strength of the wing box; whether it was strong enough to absorb loads that were well within the spar’s limits. If it wasn’t as strong as it should have been, the next question will concern the same structures on other MD-11s. Are they deficient too, or was it just a defect in the manufacture of that particular one? The same plane had been involved in two other hard landing incidents, prior to this accident. They are also examining the possibility of the pilot overcontrolling as he tried to correct after the first bounce.
It is obvious that Michael Crichton’s 1996 novel, AIRFRAME, is based on the checkered history of the MD-11, and in particular, on the deficient designs of its slats and pitch stability systems. Crichton’s N-22 (his fictitious name for the MD-11) comes out as a stellar airplane that suffers only from bad press. Likewise for the DC-10. His discussion of the misfortunes of the DC-10 (beginning on page 181, in the paperback edition) is greatly distorted, chiefly by what he leaves out of the discussion. In my view, the DC-10 is one of the worst designed airplanes to ever come down the pike and the MD-11 is not much better.
1998, September 2. A Swissair MD-11 plunged into the Atlantic Ocean, with the loss of all 229 onboard, after the pilots reported smoke in the cockpit. That investigation is ongoing and they now have evidence of a fire fore and aft of the cockpit bulkhead. Recovered parts, from the cockpit area, included a portion of the sheepskin cover from the F/O’s seat, an armrest, air filter, melted aluminum, electrical wires with melted copper, charred or missing wire insulation, and smaller parts that were discolored by heat. Those parts are undergoing analysis to determine the temperature levels and heated gases to which they were exposed, according to the TSB (Transportation Safety Board of Canada). That accident has prompted many questions received at this web site.
1999, August 22. A China Airlines MD-11 crashed while landing at Hong Kong’s Chek Lap Kok airport, during a rain storm with strong, gusting crosswinds. The right gear struck the runway very hard and then broke off, allowing the right engine and wing to strike the ground. The right wing then broke off and the plane flipped upside down. That is very similar to the type of damage incurred by the Fed Ex MD-11, when it crashed at Newark. Three of the 315 people on board Flight C1642 were killed. The rest owe their lives to the Hong Kong airport’s fire brigade that put out the fire before it engulfed those trapped in the wreckage. It took almost 3 hours to remove all the survivors.
Failure of the wings, in the area of the fuselage attach points, has called into question the structural integrity of the wing box structure of the MD-11 and is part of the focus of investigation in both accidents.
It was the same plane that was involved in the turbulence accident on Dec. 7, 1992, described above.
1999, October 17. A Fed Ex MD-11 touched down at Subic Bay, in the Philippines and then ran off the end of the runway and sunk in Subic Bay. The plane was a total loss, but the 2 pilots escaped with only minor injuries. The report found the probable cause to be:
The failure of the flight crew to properly address an erroneous airspeed indication during descent and landing, their failure to verify and select the correct airspeed by checking the standby airspeed indicator, and their failure to execute a missed approach. These failures led to an excessive approach and landing speed that resulted in a runway overshoot. Contributing factors to the accident were clogged pitot tube drain holes, the MD-11's insufficient alerting system for airspeed anomalies, and the failure of the SEL ELEV FEEL MAN and SEL FLAP LIM OVR D checklists to refer the crew to the standby airspeed indicator.
2001, November 20. An Eva Air MD-11 made a hard landing at Taipei, Taiwan. The first officer was flying the plane as it hit hard and bounced. The captain immediately took control and initiated a successful go-around. After the second landing, investigation revealed substantial damage to the nose wheel well structure and one of the two nose tires had failed.
1994, November 4. A Fed Ex MD-11 freighter made a hard landing, and a tail strike at the Anchorage, Alaska airport. After selecting 50 degrees of flaps the first officer, who was flying the plane, was not able to stabilize the approach in the pitch mode. The attitude of the plane varied approximately 2 degrees with corresponding elevator position changes. The captain, because of the high sink rate, grabbed the yoke and pulled back. The plane landed hard, bounced, and oscillated at least three times, reaching a maximum pitch up attitude of 12.3 degrees. The tail struck the runway during the oscillations. This was also the plane that crashed at Newark in 1997.
1996, May 16. A Fed Ex MD-11 freighter encountered wake turbulence from a preceding 747 as it was landing at the Anchorage, Alaska airport and suffered substantial damage. When the plane entered a high sink rate, the captain tried to go-around but the lower aft fuselage hit the runway and bounced. The captain discontinued the go-around and the plane bounced two more times, causing substantial damage to the aft pressure bulkhead.
Prior to this accident, Fed Ex did not have formal tailstrike awareness training for its MD-11 pilots. After this accident, however, Fed Ex developed a tail strike awareness training program that included bounced landing recovery in its simulator training. That program limited pitch attitude to 7-1/2 deg for recovery from a bounced landing.
1997, June. Thirteen people were seriously injured when a Japan Airlines MD-11 experienced severe pitch oscillations. One passenger went into a coma and died, 20 months later.
The pilot attempted manual recovery when the autopilot failed to detect the plane was flying too fast after an encounter with wind shear. The pilot’s repeated attempts to stabilize the altitude caused the severe oscillations that injured passengers and crew. The autopilot was blamed for the accident because it contained a programming design defect that commanded it to respond to average velocity calculations instead of actual speeds.
1997, July 31. A Fed Ex MD-11 bounced on landing at Newark airport and then flipped upside down off runway 22 R. The two pilots and three passengers managed to escape before the plane was destroyed by fire. The investigation is focusing on the failure of the right main gear, which allowed the right engine and wing to dig into the ground, flipping the plane over.
Wreckage of the Fed Ex Newark accident, July 31, 1997
There is now some question about the structural strength of the wing box; whether it was strong enough to absorb loads that were well within the spar’s limits. If it wasn’t as strong as it should have been, the next question will concern the same structures on other MD-11s. Are they deficient too, or was it just a defect in the manufacture of that particular one? The same plane had been involved in two other hard landing incidents, prior to this accident. They are also examining the possibility of the pilot overcontrolling as he tried to correct after the first bounce.
It is obvious that Michael Crichton’s 1996 novel, AIRFRAME, is based on the checkered history of the MD-11, and in particular, on the deficient designs of its slats and pitch stability systems. Crichton’s N-22 (his fictitious name for the MD-11) comes out as a stellar airplane that suffers only from bad press. Likewise for the DC-10. His discussion of the misfortunes of the DC-10 (beginning on page 181, in the paperback edition) is greatly distorted, chiefly by what he leaves out of the discussion. In my view, the DC-10 is one of the worst designed airplanes to ever come down the pike and the MD-11 is not much better.
1998, September 2. A Swissair MD-11 plunged into the Atlantic Ocean, with the loss of all 229 onboard, after the pilots reported smoke in the cockpit. That investigation is ongoing and they now have evidence of a fire fore and aft of the cockpit bulkhead. Recovered parts, from the cockpit area, included a portion of the sheepskin cover from the F/O’s seat, an armrest, air filter, melted aluminum, electrical wires with melted copper, charred or missing wire insulation, and smaller parts that were discolored by heat. Those parts are undergoing analysis to determine the temperature levels and heated gases to which they were exposed, according to the TSB (Transportation Safety Board of Canada). That accident has prompted many questions received at this web site.
1999, August 22. A China Airlines MD-11 crashed while landing at Hong Kong’s Chek Lap Kok airport, during a rain storm with strong, gusting crosswinds. The right gear struck the runway very hard and then broke off, allowing the right engine and wing to strike the ground. The right wing then broke off and the plane flipped upside down. That is very similar to the type of damage incurred by the Fed Ex MD-11, when it crashed at Newark. Three of the 315 people on board Flight C1642 were killed. The rest owe their lives to the Hong Kong airport’s fire brigade that put out the fire before it engulfed those trapped in the wreckage. It took almost 3 hours to remove all the survivors.
Failure of the wings, in the area of the fuselage attach points, has called into question the structural integrity of the wing box structure of the MD-11 and is part of the focus of investigation in both accidents.
It was the same plane that was involved in the turbulence accident on Dec. 7, 1992, described above.
1999, October 17. A Fed Ex MD-11 touched down at Subic Bay, in the Philippines and then ran off the end of the runway and sunk in Subic Bay. The plane was a total loss, but the 2 pilots escaped with only minor injuries. The report found the probable cause to be:
The failure of the flight crew to properly address an erroneous airspeed indication during descent and landing, their failure to verify and select the correct airspeed by checking the standby airspeed indicator, and their failure to execute a missed approach. These failures led to an excessive approach and landing speed that resulted in a runway overshoot. Contributing factors to the accident were clogged pitot tube drain holes, the MD-11's insufficient alerting system for airspeed anomalies, and the failure of the SEL ELEV FEEL MAN and SEL FLAP LIM OVR D checklists to refer the crew to the standby airspeed indicator.
Fed Ex, Subic Bay. The pilots were very lucky to escape this accident with their lives. It would have been a much different story if the plane had been packed with 300 passengers.........
2001, November 20. An Eva Air MD-11 made a hard landing at Taipei, Taiwan. The first officer was flying the plane as it hit hard and bounced. The captain immediately took control and initiated a successful go-around. After the second landing, investigation revealed substantial damage to the nose wheel well structure and one of the two nose tires had failed.
Gentlemen, if we could please re-focus on the airplane and its characteristics...?
Does anyone have the current FCOM "Bounced Landing" procedure and can they reproduce it here? I'm curious about what it requires the crew to do. Is the FCOM response a go-around or does it permit the crew to control the pitching? Are there two responses (either go-around or try to control pitch) depending upon the firmness of the landing? (I ask, because it seems to me that a high bounce in all transport aircraft requires a go-around whereas a smaller bounce, (I realize the Saudi report says this one bounced only 4ft) may be recovered using pitch inputs even if that means freezing the position of the stick until after the second touchdown).
The airplane exhibits behaviours that other aircraft with a more forward CofG do not. I'm curious what the FCOM has to say about this.
The more I think about the MD11, the more I think it is prone to pitch instability in comparison to other similar-sized transports and that even leaving the stick alone "frozen" for a moment in one position may not assist recovery from a bounce, which does lead a pilot into a PIO-like response.
Yet those who fly the aircraft say it is for all intents and purposes, "normal".
For those that fly the airplane, can you compare the control column motions with other types you've flown, once landing flap is selected? Are you "busier"?
Does anyone have the current FCOM "Bounced Landing" procedure and can they reproduce it here? I'm curious about what it requires the crew to do. Is the FCOM response a go-around or does it permit the crew to control the pitching? Are there two responses (either go-around or try to control pitch) depending upon the firmness of the landing? (I ask, because it seems to me that a high bounce in all transport aircraft requires a go-around whereas a smaller bounce, (I realize the Saudi report says this one bounced only 4ft) may be recovered using pitch inputs even if that means freezing the position of the stick until after the second touchdown).
The airplane exhibits behaviours that other aircraft with a more forward CofG do not. I'm curious what the FCOM has to say about this.
The more I think about the MD11, the more I think it is prone to pitch instability in comparison to other similar-sized transports and that even leaving the stick alone "frozen" for a moment in one position may not assist recovery from a bounce, which does lead a pilot into a PIO-like response.
Yet those who fly the aircraft say it is for all intents and purposes, "normal".
For those that fly the airplane, can you compare the control column motions with other types you've flown, once landing flap is selected? Are you "busier"?
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The witch hunt continues.
Let me just point out that no DC10 or MD11 was ever lost on a test/demonstration flight or by high level upsets ..... so the actual discussion seems to me like a naive diversion!
The mentioned instability inflight on MD11s only happens in cruise with fuel balance control, fuel to the aft tank. In approach configuration the aircraft has a trim characteristic as others, no more fuel aft.
The bounce recovery is mentioned as leaving ~7deg pitch and no longer attempt to land but go around, again quite similar to other aircraft.
Attempting to land with power to idle, spoilers deployed, rebounced to 20' and attitude to 6deg, by pushing onto the nose wheel sort of points to inadequate pilot technique and decision making, but not very much to aircraft design.
There is a tendency for PIO after a bounce or unstable approach, agreed, but never to the unsafe extent. MD later implemented push and pull limiters in the full configured state to mitigate this arising problem. To me this was the wrong approach, chosen because less trained pilots started flying the bird. They should have left the full authority and demand increased training/skills for the MD11 pilots.
The mushiness described in full configuration is only a consequence of lower speeds. The sops of setting Fl50 and refraining from using the equally normal Fl40 setting which gives more and better authority, was detrimental. The widespread fright by MD11 pilots about its high Va and the not very sensational braking characteristics, made them adopt the Fl50 and fly the Va to the lowest limit, some even going into Vthreshld (Va-5). All this gives a somewhat mushier experience compared to a Fl40, Va before-flare speed.
A sop and training item to me.
It is a fact that the LSAS (castrated longitudinal fly by wire, compared to the CWS of the DC10) is less agreeable to fly and should not be deactivated, as the CWS could be, for landing. This is a design flaw. MD should have left the beautiful CWS.
As for the wing box design, leave it to engineers to decide, to me it's stable enough to withhold "normal" hard landings.
Otherwise we could start building tanks that withhold crashes ....
Let me finish my remarks with branding anyone a complete moron who brings in the Swissair tragedy in conjunction with MD11 design.
Let me just point out that no DC10 or MD11 was ever lost on a test/demonstration flight or by high level upsets ..... so the actual discussion seems to me like a naive diversion!
The mentioned instability inflight on MD11s only happens in cruise with fuel balance control, fuel to the aft tank. In approach configuration the aircraft has a trim characteristic as others, no more fuel aft.
The bounce recovery is mentioned as leaving ~7deg pitch and no longer attempt to land but go around, again quite similar to other aircraft.
Attempting to land with power to idle, spoilers deployed, rebounced to 20' and attitude to 6deg, by pushing onto the nose wheel sort of points to inadequate pilot technique and decision making, but not very much to aircraft design.
There is a tendency for PIO after a bounce or unstable approach, agreed, but never to the unsafe extent. MD later implemented push and pull limiters in the full configured state to mitigate this arising problem. To me this was the wrong approach, chosen because less trained pilots started flying the bird. They should have left the full authority and demand increased training/skills for the MD11 pilots.
The mushiness described in full configuration is only a consequence of lower speeds. The sops of setting Fl50 and refraining from using the equally normal Fl40 setting which gives more and better authority, was detrimental. The widespread fright by MD11 pilots about its high Va and the not very sensational braking characteristics, made them adopt the Fl50 and fly the Va to the lowest limit, some even going into Vthreshld (Va-5). All this gives a somewhat mushier experience compared to a Fl40, Va before-flare speed.
A sop and training item to me.
It is a fact that the LSAS (castrated longitudinal fly by wire, compared to the CWS of the DC10) is less agreeable to fly and should not be deactivated, as the CWS could be, for landing. This is a design flaw. MD should have left the beautiful CWS.
As for the wing box design, leave it to engineers to decide, to me it's stable enough to withhold "normal" hard landings.
Otherwise we could start building tanks that withhold crashes ....
Let me finish my remarks with branding anyone a complete moron who brings in the Swissair tragedy in conjunction with MD11 design.
'Let me just point out that no DC10 or MD11 was ever lost on a test/demonstration flight or by high level upsets ..... so the actual discussion seems to me like a naive diversion!'
So its perfectly forgiving in the hands of an experienced Test Pilot.
Impressive..
So its perfectly forgiving in the hands of an experienced Test Pilot.
Impressive..