Pilot error blamed for Emirates near disaster at Melbourne Airport

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Deano, can I question this in a manner that is made understandable to those on this forum not familiar with aircraft weight and balance, and which is no way meant to question or undermine your professional standing.

My confusion lies in not knowing the onboard system used to calculate the desired weights and I stand to be corrected on my assumptions. This incident does however appear to highlight a failure of automated cross checking.

Unless I am very much mistaken, the three main weights used for aircraft operations are Zero Fuel Weight (ZFW) , Take-Off Weight (TOW) and Landing Weight (LW)

During the manual calculation of loadsheets, the ZFW is derived by taking the Aircraft Prepared for Service Weight (APS – Basically, the weight of the a/c as it stands including catering and any spares carried, but without fuel, passengers, baggage or cargo) and adding to it the Traffic / Payload (passengers, baggage or cargo).

To this you add the fuel weight minus the weight of fuel used for taxying to give you your Take-Off weight.

From this figure you then subtract the Burn-Off (Fuel used during flight) to give the Landing weight

In an automated system, the variables that need to be manually imputed as the weights vary are APS, Traffic/Payload, Fuel and Burn-Off. From these inputs the required three weights can be calculated and displayed

During the incident in question we are told that “The investigation has determined that the pre-flight take-off performance calculations were based on an incorrect take-off weight (262.9 tonnes, instead of 362.9 tonnes) that was inadvertently entered into the take-off performance software on a laptop computer used by the flight crew”. It was the Take-Off weight and not the Traffic Load tnat was a hundred tons less than it should have been, but why was the need to manually input this figure and even more so, how is it possible to do so? Doesn’t the system calculate this figure based on the explanation above.

OK, it was a human error that caused this incident but surely it is a fundamental error that the FMS did not pick it up.

Am I being too simplistic and missing something?

Jethro

Yes you are right, but ours calculate the ZFW for us, and our FMS is quite antiquated in relation to the rest of the aircraft.
As galdri has cleared up his FMS seems to work similar to ours where we can enter the APS weight, invariably it is already there but it is cross checked. We enter the Block fuel minus the taxi, then the traffic load and it will automatically calculate our ZFW. I'm sure the newer FMGC on the airbus does this too. The landing weight is determined by a manual calculation of a fuel check in flight using the OFP data. The FMS will give a LW figure but it is not to be relied upon. The arbiter is the OFP but the 2 should be reasonably similar.

Our FMS won't calculate V speeds either, the Vr & V2 is done by using TOLD cards and Runway Analysis Charts with the V1 being determined by the charts (not the TOLD cards).
Flap settings, flex settings, Acceleration Altitude & RTOM is taken from the RACs

Galdri I am led to believe that the FMGC on the newer Airbus series will calculate V speeds etc, all the temperatures, flex, flap settings etc can be entered and it'll spit out the V speeds and bug them along with the flap retract schedule on the PFDs.

This type of error is what brought down the MK 747-200 in Nova Scotia a few years ago, using a laptop to calculate performance data and not being cross checked by the crew.

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I think all of us that fly commercially have made a mistake reading analysis from time to time. I´ve done so myself and been found out by the other member of crew.(

Likewise, and likewise for me picking missed info up. So long as there's human intervention, there will be mistakes.

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It does indeed affect people in different ways.
But to be fair, in all of your touring have you been called upon to make fuel, weight and speed calculations on the back of a 1 to 2 hour, fairly dry session of pre-flight when you've not had much sleep beforehand.
Are you confident that you would be able to perform such duties without a mistake?.

I'm not confident I could do that regardless of how tired I was and it's something I'll never have to do, so asking me that question doesn't really work. I have, however, have been required to get on stage and perform, sort out huge technical problems on massively complex systems and other such things that require a hell of a lot of thought. I'm not trying to directly compare what I do to flying a plane and if you think I am then you completely missed my point. I've never flown a plane and the majority of pilots will never mix or play concerts to thousands of people, so neither of us are in a position to directly compare. I'm simply pointing out that tiredness affects people in different ways.

Paul

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The problem Paul is not flying the odd trip here and there, and working your socks off here and there. The problem is that there was a recognition that pilot fatigue is a big contributing factor in airline incidents/accidents, so the bigwigs in Europe brought us CAP 371 (and it's European/International equivalent), this is basically FTLs, or flight time limitations. This governs what we can and cannot work on duty over a given day/week/2 week/month/year, but employers do not view it this way. They view CAP 371 to be a maximum that they can operate their crews to. If you work to your FTLs every 2 weeks/month then you can go months working to this limit. This is why flight crew in particular are susceptible to fatigue. It can be very tiring working to FTLs over a long period.

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The problem Paul is not flying the odd trip here and there, and working your socks off here and there. The problem is that there was a recognition that pilot fatigue is a big contributing factor in airline incidents/accidents, so the bigwigs in Europe brought us CAP 371 (and it's European/International equivalent), this is basically FTLs, or flight time limitations. This governs what we can and cannot work on duty over a given day/week/2 week/month/year, but employers do not view it this way. They view CAP 371 to be a maximum that they can operate their crews to. If you work to your FTLs every 2 weeks/month then you can go months working to this limit. This is why flight crew in particular are susceptible to fatigue.

So what you're essentially saying is there are fairly major flaws in how the rules work or are made to work by airlines? Admittedly if we're tired we just have to get on with it (although if I make a mistake through tiredness and 2 tons of PA falls out of the roof, people die which isn't really very good). How often are you pushed to the limits of your allowed flying time?

Paul

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So what you're essentially saying is there are fairly major flaws in how the rules work or are made to work by airlines? Admittedly if we're tired we just have to get on with it (although if I make a mistake through tiredness and 2 tons of PA falls out of the roof, people die which isn't really very good). How often are you pushed to the limits of your allowed flying time?

Paul

No I didn't say that, you did :), I'm in no position to start a conversation on this in the public domain, and nor would I want to, for obvious reasons.

In the summer months we're pushed hard, in the winter months it's alot easier :)

As for making mistakes I guess anyone could make a mistake that ends up with someone dead, I would assume there won't be that many mistakes you can make that'll kill people in your line of work, whereas we can make a myriad of mistakes with any one of them killing alot of people.

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No I didn't say that, you did :)

Possibly a fair interpretation though when you say there's a problem and the airlines take the solution in a slightly different way to those who formulated the solution in the first place? :p

I actually almost changed my post, I realised after asking that question that it wasn't appropriate for a public forum. As far as me killing people is concerned, I'm more likely to hurt people's ears than kill them although as I say, we do put a lot of gear in the air above people so we can't take that lightly. A decent amount of rigging coming out of the air could probably quite easily flatten 40 or more people but yes, you guys certainly have more variables to deal with than we do!

Paul

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As far as me killing people is concerned, I'm more likely to hurt people's ears than kill them although as I say, we do put a lot of gear in the air above people so we can't take that lightly.

Rather you than me mate, I can't stand heights.

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Rather you than me mate, I can't stand heights.

Me neither, I get someone else to go up in the roof while I stay firmly on the ground! Not only can I not stand heights, but if I fell out of the roof it would do a hell of a lot more damage than 2 tons of speakers.

Paul

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I think your comments are a little short sighted, considering they may be underlying circumstances.

Perhaps they are, but I can't help thinking of the consequences of a major crash brought about by 'pilot error.'

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20 years 5 months

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Neither can I. But you don't see me summarily judging and convicting the pilots.

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16 years

Posts: 1,059

Neither can I. But you don't see me summarily judging and convicting the pilots.

The original report says the pilots were sacked, so whether or not I summarily judge and convict them after the fact is, ultimately, of little relevance.
As I understand it, one pilot made an elementary error that could have resulted in the loss of the aircraft and the other failed to cross-check the data input. Such is the scale of their error in the sense of possible consequences that I cannot see what 'mitigating circumstances' have to do with it.
That said, I would feel very sorry for them on an individual level.

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Emirates

Read the forums on Pprune for info from the horses mouth!Sorry Pilots!

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I was a passenger on this plane. The pilots skill actually saved us from being incinerated in a fireball. Even though it was their mistake by inputting the wrong weight, they were also using reduced thrust as it is Emirates policy to save money. The practice of using reduced thrust when taking off should be outlawed. This incident has cost Emirates far more than the cost of the fuel they saved.

Also flames flared from an engine on the right wing while taxiing before the tailstrike occurred. Was this a factor in the tailstrike? No-one has mentioned this.

The most dangerous aspects of any flight are taking off and landing, maybe Emirates and the other airline companies should reconsider the dubious practice of using reduced thrust when taking off.