Malaysian Tail Strike on take off at Zurich

[Dani]

The opposite is correct: ZRH is very famous for having unpredictable winds from the NW, i.e. tailwind on RWY 16, the departure rwy for this MAS flight. Meteo service in ZRH have a small observation hat right at THR 16. They have also a rather sophisticated wind prediction/calculation software. But still then, most of the time winds are not coming from the south, as it should be with preferential RWYs 14 and 16. It could be very likely that they got a tailwind gust on take off roll.

[411A]

Dani,

Please do explain what a 'tailwind gust' is and how it would be detrimental to aircraft performance, specifically causing a tailstrike on takeoff.

Personally have been operating into ZRH since 1977 during all types of weather, and have never had any problems on takeoff...from any runway in use...16, 34, 28.

Those who are grasping at straws to explain the particular incident clearly are overlooking the primary reason tailstrikes occur on takeoff...over-rotation and incorrect V speeds selected for the actual takeoff weight.

Loadsheet error/incorrect loading...not very likely at all.
Windshear, possible but not very probable.

Crew error, THE primary factor in these all to common incidents.

Wonder just when crews and airlines will examine their particular procedures, especially how V speeds are determined (and carefully cross-checked with the proper printed charts), whether it is indeed proper to select the very utmost flex thrust for the particular takeoff, especially in cases where it is quite critical considering the MTOW, and more sim training so these incidents can be sharply curtailed.

Don't hold your breath.

The only likely scenario is if the hull insurance companies force airlines into this extra training, due to excessive payouts to fix the damage.

[MAStake]

Combined total time of captain and fo on this flight in excess of 10 years. MAS has had 777 about 7 years so do the arithmatic.

The only truth is that there's a lot of bullsh*t floating around on the forum.

[Dani]

411A, I didn't say that the tailwind gust is the most likely scenario, I just said that ZRH is a very special airport - yes, Unique!
If you haven't had ever tailwind gusts in ZRH, then I guess you haven't been there a lot. Ask people from there (like me). I remember landing on 14, with a front closing in, flared already, but that IAS just didn't bleed off. Flaring down the rwy I gave up and went around. The Seychelles in front and the Swissair behind me did the same, btw.
If you have sudden wind speed changes (mostly refered as gusts) on take off, you suddenly have not your rotation speed but slightly lower, giving you less lift. It's maybe not the best solution to rotate further (but in theory you could get more lift with more angle), but maybe the MAS guy did just that.
Well, well, we start again with speculation. I didn't want to do that. Just wanted to explain ZRH WX situation. Maybe it can help someone next time.

[Cap 56]

I tend to agree with A 411 but looking at the picture I would think that they over rotated shortly after the main gear got airborne.

Excluding an aircraft malfunction, I would put my money on use of trim while rotating.

Just guessing, but after the EK T/O demonstration I start to believe that anything is possible once you go out of American and European aviation context.

[woodpecker]

Here we go again...

...I would put my money on use of trim while rotating...

This is a fly by wire aircraft, the trim doesnt work in the same sense as it does on a cherokee. What you have on the control column trims the speed, not the elevator, through the ACE computers (in promary mode).

Lets just wait and see...

[Cap 56]

Woodpecker

If you push the trim switches on the B 777 in manual flight it will give you pitch up or down at any speed.

Do not chalenge me on this one my friend.

I used to knopw the B 777 inside out.

[broadreach]

Cap56, it might be worth a glance at the sequence of pics earlier in the thread; it would seem that the scrape began while all main gear tyres were still squarely on the runway and continued until they were airborne.

[unmanned transport]

The FDR (Flt. Data Recorder) tape must have been deciphered by now. That will tell the true story.

[Shore Guy]

To all, please take this not as a criticism of the crew and/or airline involved. Time will be the only teller of the full and true story. However, history of such incidents point to a weight and balance/speed cards/FMC speed programming issue. Which leads me to….

All airlines teach procedures…..few teach techniques, techniques to confirm procedures are adhered to. We have all in our careers seen another pilot do something and say/think “that’s a good idea – I think I’ll do that”.

I submit the following as a technique to perhaps catch the above mentioned problem (I have heard that at some carriers this may be procedure).

Most airlines have estimated weights included in the flight planning paperwork. In fact, for fuel burns to be realistic, particularly on long haul flights, estimated weights better be close to actuals, or a last minute trip by the fuel truck will be involved. My suggestion is that there is a takeoff number that is (almost) strictly a function of weight, and that is the “outer bug” at most carriers, clean maneuver speed (there can be an argument here for V2, but that can vary with different TO flap settings, so V clean maneuver I think is best). Set (or write down) clean maneuver speed during cockpit setup and if the final numbers are significantly different, investigate why. This will normally catch the “big errors” (there have been lots of 100,000 lb. errors in large aircraft tail scrape/tailskid events). And this may catch an error in the landing numbers also…..leave the outer bug set at it’s takeoff value – when setting bugs for landing, the only variable here is fuel burn off. Come up with a quick and dirty formula for the reduction of clean maneuver (I use 3-4 K per hour of flight). If there is a big difference, investigate.

Not trying to be a smart ass here…..there for the grace of God……….But I fly backside of the clock mostly, and try to create as many techniques/tools to keep the blue side up….fatigue induced errors are often so insidious.

[Passenger 9]

4 to 5 meter scrape

Caught a squint of the 777 the other day in the SR workshop and the damage, external visable, looks like a 4 to 5 meter scrape in the appropriate place. no indication on airframe bending or internal shock load damage, it will take a while longer before we know about that.

Dani,
you say ...
"If you haven't had ever tailwind gusts in ZRH, ...... I remember landing on 14, with a front closing in, ...... Just wanted to explain ZRH WX situation."

On the day of the scrape there was no , that is, NO, with an N and an O, no front closing in. It was nice weather.

Woodpecker is looking in the right area for cause in his first post here.

Oh, and since when has the number of flight hours ever stopped someone from doing something wrong?!?

For a bit of fun consider the following.
I could sit up the front of any wide body, with 10,000 hours in my belt, eating peanuts and do my 2 take offs and hopefully also 2 landings a month and call my self experienced. If the average wide body take off long-hall has a ground roll of 50 seconds, of which 5 seconds involved is in the rotate function, then thats 10 seconds a month rotate experience. 10,000 hours divided by 7 hours per sector = 1,428 sectors. 1428 sectors with one rotate of 5 seconds per sector = 7140 seconds rotating divided by two (assuming the work is 50:50 between P1 and P2) = 3570 sec rotating = 59.5 minutes rotating a B777.
How many rotates were in good weather how many in bad etc., etc. after 1 hour or rotating experience it is quite possible for any pilot to over cook it once in a while, or to be in a position where the P1 was not able to recognise or correct a P2 instigated over rotate.

Look at the general aviation accident causes and look and see how many 10,000 hour pilots crash a PA28 through even the simplest of causes.! The total number of hours can tell you everything or nothing about a pilots ability.

Yes we need the FDR information here to help us all and the METAR from the time of the incident.

So its into the melting pot with this one, enjoy,

[Icarus]

No need for any reports and/or FDR data! Gulf Air's Ground Operations Audit Team just published the following to all its Airport Managers:
QUOTE
Malaysian Airlines B777 on departure from ZRH to KUL last week on July 28th had tail strike (see picture). After 40 minutes of fuel dumping it made a emergency landing on RWY14. Further investigation revealed that wrong loading ( Tail Heavy) was reason for tail strike.
UNQUOTE

[woodpecker]

Thanks Icarus. So there we have it,



Further investigation revealed that wrong loading ( Tail Heavy) was reason for tail strike

Nothing to do with....

a good tug at rotate should result in a nice tail scrape

It could be very likely that they got a tailwind gust on take off roll

One possibility you have not considered is windshear

Nothing was wrong with the plane, it was a training flight for the F/o

I would put my money on use of trim while rotating.

As for 411A, I don't know what jem he came up with as thanks to Pprunes "ignore list" I don't see his posts! (excellent facility)

So in the end it was down to the loadsheet/trimsheet, nothing to do with the pilots!

I rest my case

[FE Hoppy]

So Woody,

Am I to understand that you cannot rotate a miss loaded 777 without a tailstrike?

Yes missloading could lead to a tailstike but who rotates the aircraft and to what attitude.

If after reaching the correct attitude using the prescribed technique the aircraft failed to lift off at the correct speed then the choice is to wait or to rotate further. This could cause a tailstrike somewhere beyond the normal rotate position on the runway or cause a bit of a mess beyond the end of tora.

If it was so grossly missloaded so as to completely rotate to scrape angle without enough elevator authority to prevent it then so be it ,the crew could do nothing, but that would take a massive loading error wouldn't it?

[Krueger]

Here we go again...

The plane was wrongly loaded! Now , we're going into what if the pilot reacted promptly...

Come on guys...

Of course, if the pilot could manage to take-off without scrapping the tail we wouldn't be here talking about it. But how many times as anyone simulated this problem on the sim?

It looks like there was no wrong doing from the pilots and that was it.

Now, the thing we should be looking for is ways to spot the problem (wrong loading) before their consequences reach this forum.

My two cents...

[NigelOnDraft]

It looks like there was no wrong doing from the pilots and that was it

Disagree totally.

As ever, there is no evidence here, and anywhere public I am aware of, of whether the Flight Crew did a good job, or a bad job, or just what was expected of them. No doubt there is an enquiry going on, and in the fullness of time, we will see exactly what degree various factors contributed.

If you knew the first thing about aviation safety, and accidents (you, and many others above patently do not), you will realise that most accidents and incidents are caused by a combination of factors. Eliminating one of those factors will usually have prevented the accident / incident occurring, but the purpose of the inquiry will be to try and address as many of the factors as possible.

A 3rd party message, in a Ground Department publication has given blame to "loading". They do not have the authority to appotion blame, but are no doubt pointing out that an initial check has revealed a loading error.

It is a correct point that Flight Crew have the skills and tools to counteract some loading errors. Whether this crew had the skills / training, or made errors, or whether the loading error was beyond their capabilities we will see.

As an example, after one of a series of DC-8 cargo loading errors / cargo shift accidents the NTSB recommended training for Flight Crews handling techniques for CG / trim errors.

NoD

[Krueger]

NoD,

If you go back and read your on post you'll see my quote and it says "looks like", it doesn't say "There was no pilot error".

I know that until the enquiry finishes, everything else is speculation and that was just what I was trying to prevent.

And yes, I do have knowledge of Aviation Safety. And the chain of events...And if cut that chain, you probably prevent the acident/incident to happen... And that safety enquiries are there to find ways to change policies, create new procedures, etc to prevent that acident/incident to happen again...

Missing anything else?

[NigelOnDraft]

Krueger...

I do not see how you can even say "looks like"? It does not "look like" anything to me (officially).

If we want to get into speculation, I cannot recall a tailscrape purely due to a loading error. As another poster has suggested, if the thing has not sat on it's backside at the gate, then there is a good chance it shoud be correctable, albeit with some prompt and large scale inputs from the Flt Crew. However, who knows with the 777, and this particular solution? I don't...

Since you know all the bits about Flt Safety (I managed to get you there!), I am surprised you make a statement like:

It looks like there was no wrong doing from the pilots and that was it

- you have drawn a pretty strong conclusion from very flimsy evidence. It is as bad, IMHO, to "clear" the crew (as you suggest) as "blame" them.... No comment is best, until we have more info, and preferably an inquiry result.

NoD

[stilton]

Of Rotations and such

with all the attention on this MAS tailstrike in ZRH, And any implications for the Pilots invoved, regardless of what happened
in this case, incidents like these and some very minor scrapes at my airline have led to an irrational trepidation to rotate the aircraft at the correct time and rate.

On our fleet, we have four subtypes of 757/767 all with considerably different dimensions weights (cockpit layout) on the -400
all with significantly differing clearance attitudes from13 degrees on the 762 down to 12.5 on the 752 down to 9 on the 767-400
and 8 on the 757-300.

We regularly change between these aircraft on even, a daily basis
our AFM states that a proper rotation should result in an airspeed of v2+15 with a required pitch of between 7.5 to 10 degrees to achieve this.

Each one of these aicraft handle a little differently, and a more junior pilot may not see a 767 for some time (the faa has decreed that currency for one is good for all!) the 767-400 has basically the 777 cockpit without the mouse and electronic checklist
quite different.

Delta flys their 767-400's as a separate fleet.

As a result of all this and a large amount of well meaning 'lore'
passed down we have a substantial contingent of pilots who start their rotation late and then rotate extremely slowly so much so that when the thundering machine is finally allowed of the ground, you have exceeded tyre speed and rocket into the air at speeds of up to v2+50 getting close to and then sometimes exceeding flap speeds.

This is all because of a fear of hitting the tail, we have a pitch monitoring program through the DFDAU that can give us (on any of these four types) our exact pitch as we lifted off. A few seconds after take off this can be retrieved and noted and after engine shutdown you can see the landing attitude next to a list of critical attitudes for all types,

You can receive a printed warning if you get closer than 2 degrees to the limit, unfortunately this warning is only tailored to the most restrictive aircraft (the757-300) bit silly when you get a warning that you exceeded 6 degrees taking off in a 767-200 when you are good to 13.

So we have overcompensated, not to minimize the danger of the tailstrike itself, but now, not only are we being hard on the aircraft we are not meeting our performance criteria, with these 'homemade' profiles

Anyone else out there with similar experiences?

[Krueger]

NoD...

That's the second time you quote me, but still you didn't understand. What part of "looks like" is of difficult compreension from your part.

If we want to get into speculation, I cannot recall a tailscrape purely due to a loading error. As another poster has suggested, if the thing has not sat on it's backside at the gate, then there is a good chance it shoud be correctable, albeit with some prompt and large scale inputs from the Flt Crew.

If you want to speculate...Supose that the wrong loading wasn't enough for the 777 to sat on it's backside, but just barely. So with just with the right momentum (as in a rotation) the 777 could easily do it , don't you agree? My knowledge of the 777 is very limited, but the ones here flying it could enlighten us...

Oops, I didn't wanted to go into speculations...