And the winner is...
 

If the Aussies still have a spare ball-and-chain, I'd like to attach it to DeltaRed who in his first ever post wrote:

"The ground staff claim they dead-headed on the next direct service to Dubai which left "immediately".

PJ2

just to clarify for you, at EK the final loadsheet is mostly recieved by ACARS but all T/O performance calculations are calculated by the flight crew using the onboard Laptop computer and then inserted into the MCDU.

:rolleyes:Conf,


I get those numbers because they are the actual ones, move on!:ugh:

CONF iture;
No, I agree it doesn't, so perhaps V speed calculation and entry seem less plausible as one explanation. The other notion (not established fact, yet) that has been expressed, twice now, is the indication of 3 separate strikes on the runway. We might expand on this, given the cautions expressed in the FCOM which I offered on page 1. The airplane is in Direct Law in the rotation phase. I know for a fact that if the rotation of this airplane is mishandled, (ie, PF senses a high rotation rate (cautioned against) and does not strictly adhere to the FCOM procedures and instead checks forward on the sidestick), the airplane will respond very sharply to a reduced up-elevator command. I asked the question about "porpoising" because that it what the airplane may do if control of the rotation maneuver is lost through PIO, [pilot-induced oscillation]. This has happened on this type but not to those with experience on type. The key is a steady pull of 2/3rds back-stick. Check forward and the airplane will respond very sharply.

Now, this is absolutely in the realm of speculation but it is informed through knowledge and experience and not just guesswork. The cautions in the FCOM are there for a reason.

This may or may not explain the long takeoff run.

Unless thrust setting procedures were badly abused (warnings ignored and I can't see that happening), I can't see a "low power" issue on this airplane - that's not the way the airplane works.

If the thrust levers are not in either the TOGA or FLX/MCT detents a warnings, ECAM message, "THR LEVERS NOT SET" + chime + Master Caution, occur. If the Flex temperature entered in the MCDU (FMC interface) is too high (ie., higher than the OAT), the A/T - FADEC system will reference and the engines will produce, MCT - Max Continuous which would be at least equal to the maximum Flex thrust available anyway.

A weight entry error here as you describe, (ZFW into the GTOW) will not, I believe (not certain here), reduce the thrust setting dramatically, but that remains an open question for me, obviously, for the moment.


Bird On:
Thank you very much - very helpful info. The procedure I am familiar with is different, as described. Both methods work well.

White Knight - THE FACTS about the crew...... They are still here in MELBOURNE (this very minute, late on sunday evening).... EK has not whisked the crew away, and they were dealing with CASA TODAY..
-----------------------------------------------------------------------

Of course you realize, with this simple post, that you've ruined the chances for pages and pages of posts. :ok:

:ugh:Quoting PJ 2:rolleyes:

"A weight entry error here as you describe, (ZFW into the GTOW) will not, I believe (not certain here), reduce the thrust setting dramatically, but that remains an open question for me, obviously, for the moment.":=

Yes it will and is possible.:sad:

G

PJ2, slip of the finger there? The flex temp is, by definition, always higher than the IOAT. Isn't it?

Wouldn't it be nice if everyone would take the advice of one poster above and desist from speculation and wait until the official report comes out? The only fact we have to date is that the aeroplane suffered substantial damage on takeoff for reason or reasons unknown and that the pilots managed to get the damaged aircraft back on the ground in one piece without injuring one of their passengers or other crew.

I don't know it for a fact, but judging by the hearsay evidence of wheel tracks off the end of the runway and clipped LLZR aerials, they appear to have managed with some skill to avert what could well have been a catastrophic accident.

Wiley;

Quote:

---

PJ2

---

Thanks, yes I thought so too. Now I'm trying to make sense of the following from the FCOM:


–

For those still confused about Localizer antennas, check this out:
Localizer - Wikipedia, the free encyclopedia

For me, I wouldn't want to say anything about the accident until the official report comes out. Let us not argue about what happen shall we and wait for the report?

One painful accident. I went "outch!" when I saw the damage.

I have read the posts and get the drift from many (particularly perhaps aussies/Q crew) that EK have handled it completely unprofessionally.

Yet, they have supported the crew and kept them in Mel. Sent a team down to support CASA's investigation and offered complete cooperation to all parties involved bar (I suspect) the press. So a nasty incident, lots of unfounded speculation and an on-going investigation. Are the comments maybe nationalistic in foundation? Bloody ***** have had a problem bet they did this, that and the other to avoid meeting their responsibilities. Its amazing how people join the dots based upon the registry of the airline rather than facts. Wait a week and you'll find out what happened in Flight and then see whether it was a crew issue, HF issue or technical issue.

MK Flight 1602
 

ASN Aircraft accident Boeing 747-244B (SF) 9G-MKJ Halifax International Airport, NS (YHZ)

I hope history has not repeated itself.

MK Airlines Flight 1602, suffered 2 tailstrikes due to incorrect V speeds, eventually got airborne but crashed into the earthen berm 100m from the runway.

V speeds entered (incorrectly) from the BLT (Boeing Laptop Computer).

The full safety report is well worth reading.

So obviously it is quite important to have some specific information on the way the 500 serie behaves during rotation.
The way I understand it, that behavior is almost an involuntary invitation for a dual input when the guy on the left/right side don't know what is done on the other side ...
IF the triple strikes is confirmed, it could be an indication of CIO (Crew Induced Oscillation) ... Only a thought of course.

So there is here a real possibility for the crew to receive wrong data especially regarding cargo weight, so the crew determines a FLEX that does not match the real GW in case of substantial cargo was loaded without notice to the crew.

Getzo, as you do have facts, how much cargo was on board that airplane ?
225 pax cannot justify a 50 tonnes PAYLOAD matching your EZFW of 227 tonnes ... Did you try the average pax + baggage weight ?

Not a pilot, just a SLF. I have read the whole thread but with so many posts, it’s hard to remember all of them and some of the very techie ones are beyond my comprehension. So I’m not trying to promote any theories, second guess investigations, impugn anyone’s reputation or tell them how to do their jobs – just trying to understand.

To my untutored mind, the more serious aspect of this event is not the tailstrike(s) but why the plane used up nearly the whole runway (a very long one, as I understand it, well capable of allowing an A340 loaded for a non-stop flight to DXB to get off safely) and then was still so low that it took out antennae (or whatever) beyond the end of the r/w. The tailstrike(s) were a symptom of the bigger problem of the delayed t/o

Posters who sound like they know what they're talking about seem to be suggesting it's very hard to cock up take-off computations (speeds, powers settings) and that weight or flap setting miscalculations/errors should not have had that much of an effect on such a long runway.

I'm guessing that professional airline pilots don't just sit there going "Computer says no" while they gobble up 7/8ths of the r/w length without having reached take off speed and then yank the stick fully back and scrape the tail along the ground in a last gasp attempt to get the thing off the ground.

So, as I understand it, a more plausible theory is that (and, as I say, I'm not having a go at anyone) the pilot misjudged the rotation, put the nose back down leading to "porpoising" with one or tail strikes (and loss of speed?) and by the time this situation had stabilised, they were nearly at the end of the runway - is that right?

Thanks.

The figures will come out in the report but at this stage that is not something you need to know. In the good old days is was called "commercial in confidence". I've seen the figures and they are correct. You can do the maths if you need to.

Like all Airbus FBW, there is an audio/visual warning of dual input. If either pilot takes control with or without saying so (take over PB), there is also an audio/visual warning for that as well. They won't stop PIO/CIO but should reduce the chances/time. Having said that, if you're running out of runway, everyone pull together!

Midland 63

All bets are open at this time and your theory is certainly one of many that the investigators will look at.

Whatever happened on the take off, well done to the crew for getting her safely back onto the ground :ok:

Sorry you might've talked about it earlier,

Does anybody know if they actually used TOGA ??

:-) please, dont mention whatever mosques or forgiveness, i am an emirates staff and i assure, all are treated the same, whoever does a "careless mistake" gets the punishment... dont involve brothers or whatever else.. it has nothing to do with it anywhere..

This should get some thread creep :ugh::ugh::ugh:

A Boeing and an Airbus have trouble getting airborne....one hits an obstruction there are fatalities...one misses obstructions by a few feet and everyone lives...Fate is still the hunter.
B7x7 how is your recall?...If similar is happening at....you can bet the mortage on the same results...somtimes it appears there is nothying new
under the sun.

The culture at EK and particularly AAR
 

I urge every pilot who has had dealings with ek flight operations management recently to lodge a report with the ATSB about flight ops culture at Emirates, particularly the man at the top AaR. His 'i'll just sack em' approach to anyone below him who raises health and safety concerns about his uninformed dictates creates a culture where safety is very seriously compromised - there is no safe haven at ek to express safety/sleep/rest/family-impact concerns without seriously jepordising your career. Any subordination will be met with disciplinary. AaR is a serious danger to the future viability of the company, almost like your worst captain who knows everything before crm was even dreamt of. I am aware his closest managers are only following his line to keep there jobs but I know one has lodged a report about the unsafe flight operations culture thats driven from the top. AaR must be stood down immediately - for the sake of peoples lives. The positive out of this incident is that it didn't happen in the UAE where it would have been covered up. A full a thorough investigation is heading emirates way for the whole world to see. To the previous, TOGA was used at V1 when observed that they were running out of tar, that only JUST saved their lives

Triton140
" what does puzzle me is why the airline concerned chose to potentially upset the Australian regulatory agencies, the same agencies who could presumably hold the aircraft as evidence for a long time, the same agencies who ultimately determine the right of Emirates to fly to Oz, etc."

You are extreamely :ok: wrong to think that the ATSB is not aware about the action plan !! otherwise, since the incident ,a dozen of flights touched down and departed from YMML,YPPH,YSSY,YBBN...where were the ATSB ??? probably waiting for you to wake them up :D

Not surprisingly, that does puzzle me (as does the lack of media attention)

Now, you are absoluately naive in seeking media's help :ugh:

That was a huge contact area along the bottom rear of the aircraft.
Does anyone model the braking effect of that sort of drag, if the aircraft is
trying to nose up so actually pressing down on the tarmac at the rear?

How do you judge correct acceleration?
 

I'm not for a minute pre-judging the cause of this incident, however for a llong time now I've held a view that very few pilots have any way of judging whether acceleration is correct for the runway in use.

In my former life, we used to have a speed we expected to achieve by a point on the runway (it was a fighter jet, and we expected to achieve a minimum speed by 2,000ft down the runway..otherwise you'd abort the take-off).

I've always been surprised there is nothing similar on bigger acft (despite the complexities involved).

I ask many of my FOs (and other Capts) what they use to assess correct acceleration. Most people reply "just a feeling" That doesn't work for me! I've watched the trend vector on the 777 speed tape on just about every takeoff I've done in the last few years. At 100kts or so, it's a minimum of 30kts..sometimes more if you're using higher than normal thrust on a shorter runway.

But given a normal 3500m+ runway, heavy jet, normal derate (or indeed full thrust if needed...it takes about the same acceleration rate to get to rotate speed on the appropriate distance, in particular if you're using balanced field figures). So, if you're taught awareness of what you expect to see on the speed tape for acceleration, you may be better placed to pick up abnormal (reduced) acceleration. To me, its far more likely to pick that up than "sensing" that the aircraft is not accelerating fast enough..especially in the myriad conditions we operate in (the Potomac river incident comes to mind...slow acceleration in low vis ops)

Curious to see what others think of my theory? (again..not saying this is necessarily relevant to this incident, but it brings up the subject I've been passionate about for some time.)

No Speed Checks?
 

I brought this up in another thread and got the same response. I, too, have a military background and don't understand why airlines don't do this. I'd consider it essential to have at least one such check. More when you expect to have a very long roll.

Acceleration Check
 

I used to fly Falcon 50's and 900's. We had an accelerometer on the PFD that read out in real time, as well as a time to 90 knots that we could figure out. Upon brake release you would look for a certain value. If you did not have at least that number something was wrong.(Not enough thrust, brake dragging, heavier than calculated, not enough tire pressure, etc).

We could literally abort takeoff at 5 knots based on the G number displayed. Or we could wait until we hit 90 knots. If it was at or less than computed time, go. If more, abort. Shouldn't be to hard to calculate and display on these airplanes as well.

flex temp
 

PJ2 & Wiley
refreshing to see there's a couple of sensible/intelligent contributors to this thread!
Keep up the good effort.
w.r.t. the FCOM, explanation:
whatever flex temp one enters can only be higher than the actual OAT. This is the adjustment/pilot input, to fool the Fadec into thinking it is a much hotter day/conditions than actual, therefore causing it to calculate reduced thrust settings primarily to protect against expected EGT limits or exceedances, & Secondly preserving unneccessary fuelburn & extending the engine life, & noise abatement etc. In short, Big Savings for the company, compared to the 'old days'!
If no flex temp is inserted into the MCDU, then the fadec will by default use the sensed OAT(actual) to determine the T.O. parameters for the given ambient conditions, which will be higher thrust than any Flex take off roll, same as TOGA, if you were to select that detent during the roll for any required reason.
Difference between Flex to Toga, is nowadays ones reserve thrust, available at the push of the thrust lever from one detent to the next, if one gets into trouble & needs it, otherwise the engines on almost all big jets these days very seldom ever use/need use, max take off power that they are capable of delivering, for normal conditions! Wet runways & unusual circumstances excluded, naturally.
I expect you know all this, I am elaborating for the benefit of all.

RE: above
 

B.T.W my statement there excludes the A340-300, which for any lucrative load in any warm environment only knows TOGA!

A380-800 driver, easyduzzit;
No, I know you won't get a warning if you stick a higher temperature than the proper flex temp - my comment was in reference to the position of the thrust levers - if they're not in either the TOGA or FLX/MCT detent, the warning I described will sound. Thanks to both of you for sorting out the higher flex temp item; yes, the engines will run "at the flex temp entered".

Having ploughed through the 10 odd pages of this post I'm surprised nobody has mentioned the CX A340 tailstrike at Auckland some time back. After a lot of speculation about the flight crew's ability (or lack of it), incorrect aircraft handling etc it was found the tail strike was due to underinflated main gear struts which had been brought to the attention of the ground engineer, by the crew, who had dismissed it. It was found the flight crew handled the rotation absolutely correctly & the tail strike could not have been avoided given the underinflated main gear struts.
I just mention this for those "armchair" investigators who may be suggesting it's the fault of the crew. It may well be, however I don't know & neither does anyone else so maybe waiting for the investigator's report could minimise "egg on face" & give the crew the benefit of the doubt they deserve.
Just a thought :rolleyes:

As a mere SLF can I ask what may seem a very stupid question? And that is what was so different in this case to the Ryanair tail strike at Dublin last year? I seem to recall the captain of the Ryanair flight declaring a mayday after that and
even discussion about leaking hydraulic fluid,what is so different between the two aircraft types that the amount of damage sustained in this event doesn't seem to have involved that sort of issue and was the Ryanair incident and the reaction of the captain an over reaction?
BTW I'm not saying the Ryanair captain did anything wrong-just asking.
I also seem to recall that in the Ryanair case there was even questions about pressurising the airframe after the event,why was that not an issue here?

Nobody dragged the tail of the plane through some aerials 300 metres off the end of the runway in Auckland or Dublin - I don't think these incidents are comparable......

I feel for these guys and never want to be in this situation - These things are always more complicated than you think - but the only way I can think you don't get off the runway is if you are overloaded / have too little thrust or if you under-rotate initially - time will tell.

That’s what I call the nice theory behind Flight Crew Operation or Flight Crew Training Manuals but when time runs out and stress level sharply increases there are 2 independent humans trying their best on 2 independent sidesticks and the final mixed output can be very undesirable and therefore counterproductive …

A gross error on the TOW could explain what happened by selecting inappropriate high FLEX temp …
To me 225 pax add up for a payload of 25 tonnes but not the double as you indirectly mention. But as you seem to be pretty sure of your figures, is it possible the crew was not made aware of an extra 25 tonnes of cargo … ?
Just one of the possible scenarios …

I'm not for a minute pre-judging the cause of this incident, however for a llong time now I've held a view that very few pilots have any way of judging whether acceleration is correct for the runway in use.


Our rule of thumb is 80kts by 1000" markers or you are heavier than estimated. This would also work for selecting wrong power as the power setting is not sufficient for a/c weight. Works pretty well.

Any others use this?

any cctv footage?
 

just like the a320 landing on the hudson in the US, any cctv footage of the EK tail strike?

CONF iture

Those figures were the original ones given to the crew on the flight plan. They are used for initial input into the MCDU and are then updated when the flight closes and a final ZFW is given. The fuel requirements are then finalised, inserted in the MCDU & then the performance figures are computed. Any significant change after that should be advised to the crew who would then get new performance figures. You would also check the loadsheet to confirm the ZFW, T/O wt & Ldg wt.
I don't know the cargo set up to catch errors but as I said before, until details emerge, all bets are open: human and/or technical.

To err is human, to really :mad::mad: it up just add a computer/stress/more humans/time change/management etc etc

I don't normally get involved on these theads, just a watcher being long retired, but I can't let this on go. When I flew Valiants we had a check time to 100 knots to make sure accel. was OK. If speed was down we aborted, did once, we went off the end, slowly. That check might well have saved Emirates at MEL.

When I converted to civil jets, BOAC VC10s I was surprised that no such check existed, however, it was BOAC so surely they knew best. Some years later as a B737 Capt. I got involved in designing a TOPIS, Take Off Performance Indicator System, it got shelved, not needed, too hard box. The electronics then were not as they are now.

I see no reason why when the performance of a sophisticated electric jet such as an A340, say, is calculated the FMC cannot calculate exactly what the accleration rate should be, considering all parameters such as thrust, temp. flap setting, weight and runway characteristics, and assign THAT rate to one pointer on a scale, on , say, the HSI or ADI The exact acceleration could then be extracted from the IRSs and another pointer driven alongside the other (rather like Concorde's speed/C of G pointers) so a direct comparison could be made between planned accel. and achieved accel. to say, 100k. Should be easy to do AND interpret.

On too many aircraft, certainly those that I have flown, we ASSUME, but do not know, that the tyres (and therefore brakes) are all intact and that the brakes are all cool, and able to accept the energy of a rejected take off at V1.

How many flight manuals contain data on tyre limitations, (although speeds such as TSOC62, 225 mph. if I rememenber correctly are indicated on the tyre mouldings) such as the maximum taxi distance at given weights before the tyres overheat to the risk of possible failure ?

Many years ago I wrote a paper for the International Journal of Flight Safety (only one edition published before the publisher died).

In that I questioned why it was not an airworthiness requirement for ALL jet transports to be fitted with brake temp. guages (sure indicator of a dragging brake as I experienced once on a VC10, ) and tyre failure indicators (like Concorde and even on my BMW) which tells me I have lost one tyre and TWO brakes assuming I want to brake in a straight line. (which I did once in a 737, fortunately during push back when a brand new wheel casting failed).

Does the A340 have brake temp. guages and tyre failure indicators, and what else could cause it to fail to become airborne on a 12,000 feet runway, even at max. gross, except too little thrust or a totally wrong flap setting, assuming the crew (of 4) would have immediately spotted gross overloading or an unexpected large tailwind ?


I believe the lack of information about take off acceleration is one of the last missing pieces in the aviation safety jigsaw, and SO easy to correct with modern electronics. Any constructive comment ?

PS Sorry if I have not used correct AB terminolgy, spent a long time on Boeings, 73, 75, 76, never flown a 'bus.

Retired BA/BY - yes the whole EK Airbus flight has TPIS and wheel temp indications..

As for judging the acceleration rate by " feel" , lets not forget that EK MFF policy has the bus drivers flying 3 variants 332/343/345. Each with very unique acceleration qualities. Add a wide variety of weight regimes ( anything from a light 332 going to DOH) to a heavy 345 out of MEL. Also anything from max flex to Toga. Artificial rotation feeling that is different on the 345 to the other two. I recall a ' dead space' at about 2/3 back stick as a result of different rotation logic on the A345.

MFF does have its dangers.

The Boeing product has a very obvious trend arrow that indicates acceleration during the takeoff roll. Anything under a 15kt acceleration trend and the alarm bells should ring that something is not going according to Hoyle. It is partiularly used for noticing the early onset of windshear. I seem to recall that the Airbus has a similar trend arrow. Someone will correct me if I am wrong.

Very perceptive Capn' Kremin.

At 1600Lt MEL today the a/c was in front of the John Holland hangar and being guarded by people sitting on chairs. The damage to the rear 'belly' is covered by tape. A BP tanker was in close proximity. I do not know if the a/c was to be de-fuelled.