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-   -   ZSPD Cargo Plane Crash (https://www.pprune.org/accidents-close-calls/397211-zspd-cargo-plane-crash.html)

Smilin_Ed 15th Dec 2009 23:52

Acceleration Check?
 
As with Emirates at MEL, an acceleration check would have saved the day.

DC-ATE 16th Dec 2009 01:46


...an acceleration check would have saved the day.
And, if as Weapons_Hot noted took place, perhaps WITHOUT relying on all the automatic stuff and setting take-off power manually, might've saved the day as well. IF this is in fact what happened.

bugg smasher 17th Dec 2009 22:35

A couple of things here;

An acceleration check, as with correct V-speeds and distances, is predicated on accurate calculation of aircraft weight, specific runway-legal weight limits, and resultant flex temp values. As a possible contributory factor, did this crew have the specific data for that runway, or did they use the generic charts from the AFM performance pages?

The ATS ‘grabs’ the throttles noticeably, even had the TO CLAMP annunciation been overlooked, that grab is all the more significant by its absence. So I think not, but you never know, fatigue has a way of making good pilots inattentive, extreme fatigue, dangerously so.

As an aside, the acceleration check, in my view, is traditionally assigned to the Flight Engineer (really wish I had the salty ‘ol bastards back, nothing like a flying spanner to whack an outa-control copilot into shape :)). A very valuable one no doubt, but the two-man-crew PF/PNF concentration requirements on a critically loaded heavy jet takeoff roll normally make this additional tasking a possible detriment, a dangerous distraction even, to the safety of the maneuver. Low visibility and contaminated surfaces make it even more so.

The takeoff, it goes without saying, should have been determined successful before the aircraft leaves the chocks.

Smilin_Ed 17th Dec 2009 23:01

Sanity Check
 
Alright, let's call it something else. I call it a sanity check. As DC8 points out, IF there was a mistake in the takeoff calculations, by computer or manually, and IF the power setting was actually too low, someone (the captain) should have said, "Hey, this isn't close to the power setting used for the last takeoff I made under these conditions!" That's why he's the captain. He has the experience to decide if what is calculated is reasonable. If it isn't, the captain should demand a recheck and also should do it himself. The same thing for an acceleration check. It's pretty rough, but if you don't get what you should expect pretty early in the roll, you should stop, go back, and recheck. That's better than plowing up the ground at the far end. You're putting your life on the line if you blindly accept what comes out of a calculator. Simply ask, does this make sense? I'll bet the guys at MEL wish they had done a sanity check.

WrldWide 17th Dec 2009 23:32

Whatever "check" one chooses to assign to the situation, the" power lever through the boost bar", rendering 62k is always permissable. If an experienced crew on the 11 was going down the runway and did not feel the aircraft had adequate acceleration, one would expect full thrust application. Something else is at play here. Hopefully the news will leak down to the operator level.
WW

Binthere 15th Jan 2010 08:31

Any answers yet on this one, too many questions and its gone very quiet?

Huck 15th Jan 2010 12:26

Read post 268.

wingview 15th Jan 2010 18:55


Read post 268.
I can't believe they missed the clamp mode. PM should see this as mandatory. If this would be the case, what a waste...

Huck 18th Jan 2010 02:30


I can't believe they missed the clamp mode
I don't have access to my books right now, but I think "CLAMP" is displayed even with A/T's off....

charter man 27th Jan 2010 11:48

Avient MD11 back in the air
 
Avient are back in the air with another MD11 - reg Z-BAT - ferried from MIA to LGG. One of the contributors on Freight Dogs say they are trying to recruit an experienced loadie instructor, this rather sounds like a cart before the horse scenario?

Weapons_Hot 2nd Feb 2010 02:46

FMA changes
 
Fogrunner

Also, at 80kt, the FMA T/O THRUST changes to CLAMP (and the "green box" or any items in the essential takeoff items checklist disappear; the FD pitch bar biases into view).
At 100kt, the ABS (provided in T/O) will change deceleration rate to MAX.

A very wise chief pilot once said of the FMA, "you live and die by the FMA".
Never truer words spoken, and no inference should be made to the crew this accident.

On the MD11, it matters not what is set on the FCP, FMC or what you perceive is set or not, or happening; unless it is on the FMA, it isn't happening or won't happen.

Still, I want to know WHY.

Finn47 22nd Feb 2010 04:12

Worth mentioning perhaps that today, after OH-LGG returns from Delhi, Finnair will retire the MD-11 from passenger service. It´s the very last scheduled passenger revenue flight. The aircraft is later destined for Singapore for freighter conversion. Besides, Finnair presently has two of them for sale. Any takers?

Feathers McGraw 27th Jun 2020 16:41

I came back to revisit this thread after nearly 11 years, I had always wondered if an official report would be released but so far that appears not to have happened.

Aviation Herald updated their article earlier in the year, adding this information, translated from Chinese, which formed the abstract of the unreleased report.

It makes for sorry, if predictable reading.

"The crew did not properly operate the thrust levers so that the engines did not reach take off thrust. The aircraft had not reached Vr at the end of the runway and could not get airborne.

According to the design criteria of the MD11 the crew needs to push at least two thrust levers to beyond 60 degrees, which will trigger autothrust to leave "CLAMP" mode and adjust the thrust to reach the target setting for takeoff, the servo motors would push the thrust levers forward in that case. During the accident departure the pilot in the left seat did not advance the thrust levers to more than 60 degrees, hence the server motors did not work although autothrust was engaged bur remained in CLAMP mode and thus did not adjust the thrust to reach takeoff settings.

The crew members perceived something was wrong. Audibly the engine sound was weak, visibibly the speed of the aircraft was low, tactically the pressure on the back of the seat was weaker than normal. Somebody within the crew, possibly on the observer seats, suggested the aircraft may be a bit heavy. The T/O THRUST page never appeared (it appears if autothrust is engaged and changes from CLAMP to Thrust Limit setting. Under normal circumstances with autothrust being engaged a click sound will occur as soon as the thrust levers reach the takeoff thrust position. A hand held on the thrust levers will feel the lever moving forward, however, the crew entirely lost situational awareness. None of the anomalies described in this paragraph prompted the crews members' attention.

When the aircraft approached the end of the runway several options were available: reject takeoff and close the throttles, continue takeoff and push the throttle to the forward mechanical stop, continue takeoff and immediately rotate. The observer called "rotate", the captain rotated the aircraft. This shows the crew recognized the abnormal situation but did not identify the error (thrust levers not in takeoff position) in a hurry but reacted instinctively only. As the aircraft had not yet reached Vr, the aircraft could not get airborne when rotated. As verified in simulator verification the decision to rotate was the wrong decision. The simulator verification showed, that had the crew pushed the thrust levers into maximum thrust when they recognized the abnormal situation, they would have safely taken the aircraft airborne 670 meters before the end of the runway. The verification also proved, that had the crew rejected takeoff at that point, the aircraft would have stopped before the end of the runway.

The crew did not follow standard operating procedures for managing thrust on takeoff. The crew operations manual stipulates that the left seat pilot advances the thrust levers to EPR 1.1 or 70% N1 (depending on engine type), informs the right seat pilot to connect autothrust. The pilot flying subsequently pushes the thrust levers forward and verifies they are moving forward on servos, the pilot monitoring verifies autothrust is working as expected and reaches takeoff thrust settings. In this case the left seat pilot not only did not continue to push the thrust levers forward, but also called out "thrust set" without reason as he did not verify the takeoff thrust setting had been achieved.

It is not possible to subdivide the various violations of procedures and regulations. The crew had worked 16 hours during the previous sector. In addition, one crew member needed to travel for 11 hours from Europe to reach the point of departure of the previous sector (Nairobi Kenya), two crew members need to travel for 19 hours from America to the point of departure of the previous sector. These factors caused fatigue to all crew membes. The co-pilot was 61 years of age, pathological examination showed he was suffering from hypertension and cardiovascular atherosclerosis. His physical strength and basic health may have affected the tolerance towards fatigue. All crew members underwent changes across multiple time zones in three days. Although being in the period of awakeness in their biological rhythm cycle, the cycle was already in a trough period causing increased fatigue.

The captain had flown the Airbus A340 for 300 hours in the last 6 months, which has an entirely different autothrust handling, e.g. the thrust levers do not move with power changes in automatic thrust, which may have caused the captain to ignore the MD-11 thrust levers. The co-pilot in the right hand seat had been MD-11 captain for about 7 years but had not flown the MD-11 for a year. Both were operating their first flight for the occurrence company. The two pilots on the observer seats had both 0 flight hours in the last 6 months.

The co-pilot (right hand seat) was pilot flying for the accident sector. The captain thus was responsible for the thrust management and thrust lever movement according to company manual. A surviving observer told the investigation in post accident interviews that the captain was filling out forms and failed to monitor the aircraft and first officer's actions during this critical phase of flight.

There are significant design weaknesses in the MD-11 throttle, the self checks for errors as well as degree of automation is not high.

"


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