EK407 Tailstrike @ ML
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that just won't happen for all sorts of circular 'legalistic' reasons that relate to the 'chain of command' ='chain of culpubility'
In short- the buck stops in the LHS!
But Wiley is 'on to it'-he/she is taking a more global approach to a systemic pre-flight problem.
And he's/she's absolutely correct!
We've allowed ourselves to be progressively compromised over the years to accepting
-interuppted briefings
-dispatchers with '2 ways' on max volume bursting onto the flight deck
etc etc
now some need to be there-
engineers have no-where else to go to sign off the tech log
FA's need to get tea/coffee orders
But it's typically mayhem....
We've all seen it-tried to manage it amongst revised slots, de-ice etc etc
but in the midst of that don't go finger wagging 'cos someone cocks-up a data entry on a single day.
It really deserves some attention-given we spend so much time and money on CRM
Vino over and out.....
In short- the buck stops in the LHS!
But Wiley is 'on to it'-he/she is taking a more global approach to a systemic pre-flight problem.
And he's/she's absolutely correct!
We've allowed ourselves to be progressively compromised over the years to accepting
-interuppted briefings
-dispatchers with '2 ways' on max volume bursting onto the flight deck
etc etc
now some need to be there-
engineers have no-where else to go to sign off the tech log
FA's need to get tea/coffee orders
But it's typically mayhem....
We've all seen it-tried to manage it amongst revised slots, de-ice etc etc
but in the midst of that don't go finger wagging 'cos someone cocks-up a data entry on a single day.
It really deserves some attention-given we spend so much time and money on CRM
Vino over and out.....
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Interesting rule of thumb iflytb20, havent heard of it yet 
I would think however it only works if you use standard speeds and not improved climb speeds which can easily lead to 160kt+ Vr for 50t weights (-3/-7 obviously).
I would think however it only works if you use standard speeds and not improved climb speeds which can easily lead to 160kt+ Vr for 50t weights (-3/-7 obviously).
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170 kts, 30 Flex, Flap3 should about do it for 363.
A heavy A340 pretty much always takes off in Flap 3, flag number 1.
Flex 74 is max flex i.e. light weight data, flag number 2.
Rotate and Green Dot way out of the gross error range, flag number 3.
A heavy A340 pretty much always takes off in Flap 3, flag number 1.
Flex 74 is max flex i.e. light weight data, flag number 2.
Rotate and Green Dot way out of the gross error range, flag number 3.
I would have another question :
Using the laptop for the performances, can you force an input value such as CONF 1+F ?
... and again what would have been the Vr and FLEX values ?
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All good stuff,
Must be some lessons to be learnt.
When I go shopping, a small basket=$10, big basket=$20, small trolly=$40, big trolly=$60+, I don't always check the bill detail, but I check the bill zone.
Brings to mind an old story of an Air Florida 737 departing IAD I think, poss 1982 may be, they got reqd EPR IND but less N1 and thrust than needed, result was bad.
I liked the previous post of a wide guage plate just like the ones for other systems likes Flaps nd Gear on some aircrafts.
I've said it before, well done to the crew involved, great end result, only hope we learn the lessons and make flying even more safe.
Edit. Thinking on, I wonder how many similar type events have been saved from the press by crew Stopping or TOGA being applied when crew aware things are not what they might be, may be !!!
Must be some lessons to be learnt.
When I go shopping, a small basket=$10, big basket=$20, small trolly=$40, big trolly=$60+, I don't always check the bill detail, but I check the bill zone.
Brings to mind an old story of an Air Florida 737 departing IAD I think, poss 1982 may be, they got reqd EPR IND but less N1 and thrust than needed, result was bad.
I liked the previous post of a wide guage plate just like the ones for other systems likes Flaps nd Gear on some aircrafts.
I've said it before, well done to the crew involved, great end result, only hope we learn the lessons and make flying even more safe.
Edit. Thinking on, I wonder how many similar type events have been saved from the press by crew Stopping or TOGA being applied when crew aware things are not what they might be, may be !!!
Last edited by Joetom; 8th May 2009 at 20:17.
what is the range of rotate speeds possible for this a/c at Flap 3 and 360T?
I expect there will be a large range from what you have said, and that will confirm that my idea is not practical as a gross error check.
I expect there will be a large range from what you have said, and that will confirm that my idea is not practical as a gross error check.
I'm like an old dog with a bone and am still keen to see if a cheap as chips plaque could have made a difference on this particular flight when they knew their weight but the speeds were wrong.
Why not just apply your applicable companies SOPs? 
I agree with the sentiment that attention needs to be brought to ...bear?.. beer? ...bare on the flightdeck environment when these calculations/briefings are being done. I often observe ground staff bursting into the flightdeck having started their questions and statements without regard to what is happening inside. I don't blame them, they have obviously not been trained properly. A ten minute video on the consequences of distractions at this stage of preparations would probably do the trick.
I'm learning a lot from this thread,
Regards, Framer
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Aviation Reports[G]skins%2ftaicAviation%2fskin_aviation
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LPC Laptops
A belated answer to post #858 by CONFiture:
YES, you can force the laptop into any approved take-off configuration.
It will provide the applicable figures, if a valid solution is available, or it will make clear that with the selected conditions, take-off is not possible.
Often airline managements will obligate the crews to use the OPTIMUM configuration output, because they fall for the word OPTIMUM.
In the instructions for the performance programs, you can read what the meaning is of the OPTIMUM CONFIG: it is the configuration, which will enable the highest lift capacity under the entered conditions, when using FULL THRUST.
The configuration that is thus determined will also be labelled OPTIMUM under conditions of reduced thrust.
The configuration that is labelled OPTIMUM often, but not always, also provides the highest lift capacity with reduced thrust. However, many times the assumed temperature that rolls out at lower flap settings is the same, or just 1 degree lower, than for the OPTIMUM CONFIG.
Often, the performance based maximum mass that can be lifted off a runway is far above the structural mass limit of the aircraft. Often, the differences between the Optimum and the other configurations amount to just a few hundred or a few thousand kilo’s, with all configuration providing performance far above the structural limit (FULL THRUST condition)
Yes, it is true that a higher performance limited mass gives you more margin in case of an engine failure, but seriously, a few hundred kilo’s difference on a total of more than 350 tonnes is not gonna give you much extra margin.
Realizing that the performance of the lower flap settings is hardly any less ON THE RUNWAY, it may be worthwhile to look at the performance once airborne. The climb performance with CONF 3 (an approved landing flap setting!) of course is abysmal, compared to a climb out with CONF 1.
The management bean counters should have a look at the amount of fuel that could be saved by the better climb performance! Than they would quickly reconsider their insistence on the use of laptop derived OPTIMUM CONFigurations.
Using minimum flap for take-off and only more flap when required for performance, would make it easier for crews to establish a mental reference of what is normal in terms of speeds for a certain mass (but yes, I know that also in fixed flap operations, errors are made).
P.S. This post is not a sneer at Airbus, their performance instructors properly explain the use of the laptop procedures, it is airline managements that order the improper use of the equipment.
Next point.
One important phrase from the ATSB preliminary report is about the use of the laptop(s). One laptop was used, the other was kept as spare, in case of breakdown of the first one. WRONG WRONG WRONG!
If pilot 1 closes the laptop and pilot 2 opens it again, to check the calculation, he will be staring at a screen with all the numbers as filled in by number 1! When glancing over numbers as a check, it is easy to overlook errors.
Pilot 2 should have autonomously filled in numbers on his own laptop and pilots 1 and 2 should have compared the outcome of their respective calculations. In that way, there would have been a comparison of independent calculations.
I do not know what the Emirates SOP’s were with respect to laptop use.
YES, you can force the laptop into any approved take-off configuration.
It will provide the applicable figures, if a valid solution is available, or it will make clear that with the selected conditions, take-off is not possible.
Often airline managements will obligate the crews to use the OPTIMUM configuration output, because they fall for the word OPTIMUM.
In the instructions for the performance programs, you can read what the meaning is of the OPTIMUM CONFIG: it is the configuration, which will enable the highest lift capacity under the entered conditions, when using FULL THRUST.
The configuration that is thus determined will also be labelled OPTIMUM under conditions of reduced thrust.
The configuration that is labelled OPTIMUM often, but not always, also provides the highest lift capacity with reduced thrust. However, many times the assumed temperature that rolls out at lower flap settings is the same, or just 1 degree lower, than for the OPTIMUM CONFIG.
Often, the performance based maximum mass that can be lifted off a runway is far above the structural mass limit of the aircraft. Often, the differences between the Optimum and the other configurations amount to just a few hundred or a few thousand kilo’s, with all configuration providing performance far above the structural limit (FULL THRUST condition)
Yes, it is true that a higher performance limited mass gives you more margin in case of an engine failure, but seriously, a few hundred kilo’s difference on a total of more than 350 tonnes is not gonna give you much extra margin.
Realizing that the performance of the lower flap settings is hardly any less ON THE RUNWAY, it may be worthwhile to look at the performance once airborne. The climb performance with CONF 3 (an approved landing flap setting!) of course is abysmal, compared to a climb out with CONF 1.
The management bean counters should have a look at the amount of fuel that could be saved by the better climb performance! Than they would quickly reconsider their insistence on the use of laptop derived OPTIMUM CONFigurations.
Using minimum flap for take-off and only more flap when required for performance, would make it easier for crews to establish a mental reference of what is normal in terms of speeds for a certain mass (but yes, I know that also in fixed flap operations, errors are made).
P.S. This post is not a sneer at Airbus, their performance instructors properly explain the use of the laptop procedures, it is airline managements that order the improper use of the equipment.
Next point.
One important phrase from the ATSB preliminary report is about the use of the laptop(s). One laptop was used, the other was kept as spare, in case of breakdown of the first one. WRONG WRONG WRONG!
If pilot 1 closes the laptop and pilot 2 opens it again, to check the calculation, he will be staring at a screen with all the numbers as filled in by number 1! When glancing over numbers as a check, it is easy to overlook errors.
Pilot 2 should have autonomously filled in numbers on his own laptop and pilots 1 and 2 should have compared the outcome of their respective calculations. In that way, there would have been a comparison of independent calculations.
I do not know what the Emirates SOP’s were with respect to laptop use.
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EMIT, thank you for your interesting extensive answer.
If I understand it well, by using the LPC laptop, crews end up using CONF 3 when most of the time 2 or even 1, for a mere flex degree or even a single knot, would be as good if not better.
So I’m glad we’re still old fashion by using the paper performance charts where it is definitely easier to keep an overall view. And I can hardly see anyone entering a paper chart 100 tonnes off !?
Also, with a book, one guy extracts some figures, then closes the book. When ready the other guy proceeds with its own independent calculation, usually both results don’t even differ enough to worth mention.
If I understand it well, by using the LPC laptop, crews end up using CONF 3 when most of the time 2 or even 1, for a mere flex degree or even a single knot, would be as good if not better.
So I’m glad we’re still old fashion by using the paper performance charts where it is definitely easier to keep an overall view. And I can hardly see anyone entering a paper chart 100 tonnes off !?
Also, with a book, one guy extracts some figures, then closes the book. When ready the other guy proceeds with its own independent calculation, usually both results don’t even differ enough to worth mention.
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Exactly, CONFiture, and indeed we even do not use the OFP as a bookmark to the "correct" runway page, so that the other guy will really start from scratch in his independant performance calculation.
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Great post EMIT
The other thing people should remember that the Green Dot speed displayed on the MCDU perf takeoff page is calculated using the TOW in the MCDU init-b Page.
If you press F9 on the LPC then it generates a Perf takeoff page with a Green Dot speed calculated usig the TOW entered in the LPC.
Assuming your loadsheet too MCDU check is water tight, the Green Dot speeds must be the same. IF NOT WHY?????? This is if you use 1 or 10 laptops.
The other thing people should remember that the Green Dot speed displayed on the MCDU perf takeoff page is calculated using the TOW in the MCDU init-b Page.
If you press F9 on the LPC then it generates a Perf takeoff page with a Green Dot speed calculated usig the TOW entered in the LPC.
Assuming your loadsheet too MCDU check is water tight, the Green Dot speeds must be the same. IF NOT WHY?????? This is if you use 1 or 10 laptops.
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Question from the other end
It went all the time through my mind, and I could dark remember that I heard it on a course:
A345 AMM
This FCPC law is engaged during rotation phase.
A pitch demand depending on pitch rate and side stick position is added to the ground law orders.
This law avoids tail strike if there is a side stick input from the pilot.
How the guys got managed to override this ?
A345 AMM
4
Pitch rotation law for takeoff
This FCPC law is engaged during rotation phase.
A pitch demand depending on pitch rate and side stick position is added to the ground law orders.
This law avoids tail strike if there is a side stick input from the pilot.
How the guys got managed to override this ?
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Why Laptop 'Optimum' is Often Wise
Often airline managements will obligate the crews to use the OPTIMUM configuration output, because they fall for the word OPTIMUM.
Many Airbus operators know the background for OPTIMUM (as you correctly say it's the flap setting that allows the theoretical max weight to be lifted off the runway...)
BUT they are NOT necessarily 'falling' for anything by choosing OPTIMUM as a standard procedure.
No. The simple reason is this; if OPTIMUM were NOT used by the crew, it leaves the process open to pilots making a large number of laptop calculations... fiddling with various flap settings (1/2/3) while they 'explore the envelope' to see what the max flex is. That's probably NOT a good idea. Why?
Because MORE laptop calculations for a single takeoff, means a GREATER chance of a MISTAKE
Using OPTIMUM CUTS DOWN the number of calculations... and makes it clear to crew they are not supposed to run calculations at various flap settings to find the max flex.
Considering the minimum financial gains from using a flex value a degree or two greater... clearly running more than one calculation to maximize flex is really a waste of time. Particularly when unnecessary calculations can add significantly to the risk.
Some airlines might be better off using TOGA everywhere... (when even one event costs millions of dollars and (mis)use of flex is often a factor).
Although this is not likely a practical solution in management's eyes, because that airline may be ridiculed in the industry, TOGA everywhere might still be safer. Considering the number of events which would have successful takeoffs, instead of running into the grass at the end of the runway (before finally getting airborne).
Worth thinking about.
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Originally Posted by AirBusted320
Considering the minimum financial gains from using a flex value a degree or two greater... clearly running more than one calculation to maximize flex is really a waste of time.
The main two FCOM procedures are :
- Use the conf giving the max flex.
- If equivalent flex is obtained, choose the conf giving the lowest speeds.
So this is not possible to maximize flex more than the computer already did, but as EMIT mentioned, it is sometimes possible for the same flex or one only marginally lower, to reduce the conf and therefore significantly improve the climb performance.
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How Airbus LPC Program Chooses Optimum Flap Setting
Internal-programming causes the Airbus LPC (Less Paper Cockpit) program, as far as Flap setting goes when OPTIMUM is left as the default, to choose the Flap setting that allows the maximum aircraft weight to be lifted off the runway.
For example, say the actual aircraft weight for takeoff is only 175T. The LPC program will calculate what Flap setting could lift 230T (or perhaps even more) and use the Flap setting for that 230T figure (disregarding the fact that the actual weight plugged into the laptop is much less).
What some pilots will then do, is go into the program and play around with the Flap setting to see if they can get a greater Flex (and use less thrust).
Why they do that, I don't know. Generally not wise, unless choosing a greater Flap setting for other reasons, such as tail clearance to avoid a tailstrike (FCTM contains text guidance that tail clearance is increased with a greater Flap setting - but tailstrike is really not a problem if SOPs are followed, anyway).
Playing with LPC flap settings is against FCOM SOP guidance (at a number of companies) is likely of little benefit (as far as we pilots are concerned) because pilots do not get paid extra for doing additional calculations with different flap settings. In fact, they may actually be punished for playing around with the Flap setting in the LPC... if they make a calculation or other mistake as a result.
If it ain't broke, don't
with it. Safer for the career.
For example, say the actual aircraft weight for takeoff is only 175T. The LPC program will calculate what Flap setting could lift 230T (or perhaps even more) and use the Flap setting for that 230T figure (disregarding the fact that the actual weight plugged into the laptop is much less).
What some pilots will then do, is go into the program and play around with the Flap setting to see if they can get a greater Flex (and use less thrust).
Why they do that, I don't know. Generally not wise, unless choosing a greater Flap setting for other reasons, such as tail clearance to avoid a tailstrike (FCTM contains text guidance that tail clearance is increased with a greater Flap setting - but tailstrike is really not a problem if SOPs are followed, anyway).
Playing with LPC flap settings is against FCOM SOP guidance (at a number of companies) is likely of little benefit (as far as we pilots are concerned) because pilots do not get paid extra for doing additional calculations with different flap settings. In fact, they may actually be punished for playing around with the Flap setting in the LPC... if they make a calculation or other mistake as a result.
If it ain't broke, don't
with it. Safer for the career.
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Playing with LPC flap settings is against FCOM SOP guidance (at a number of companies) is likely of little benefit (as far as we pilots are concerned) because pilots do not get paid extra for doing additional calculations with different flap settings.
First of all, it is not merely "playing" with flap setting if a pilot choses another setting. As it seems to be against SOP, it shows that the issuers know as little about that matter than the pilots adhering to them religiously.
You rightly pointed out that the computer goes for the setting giving the most weight in relation to the lowest power setting. That's what it is programmed to do, point. The pilot however can take into consideration much more than that. For example surface condition. With an extremely rough surface he can go for a higher flap setting, as to get airborne earlier. If there are no obstacles impeding such a choice, it might be even the safer one. So why would SOP interdict that?? If windshears are predicted, icing or turbulence at low level, the pilot might opt for a lower flap setting as to get better climb performance and better power/drag ratios. If the runway is long enough and no other parameters against such a choice, why shouldn't the pilot be allowed to chose such a setting??
It all comes down to knowledge of aerodynamics and performance of your aircraft, because this raises the overall awareness of what might happen and what the values should look like. If we just punch in some numbers, and we all agree that this can go wrong, and we are only allowed to do exactly this, then we need zillions of crosschecks so it will never go wrong, instead of the good old gut feeling that this just doesn't look right.
Another point. I stated earlier that with the computers at EK, you could chose another flap setting. However you cannot chose a lesser flex/assumed temperature. This forces you to take either the lowest possible (proposed flex) or the highest possible (Max). Again, if some windshears are predicted, a low level inversion etc. etc. and you are light, the max power is not a very astute choice. Neither is the max flex . If you could reduce the flex by 5 to 10 degrees, you would be able to add a healthy and safe margin. The only way to build in a inbetween safer margin, with EKs procedure, would be to increase the weight input into the laptop. But you don't want to do that in the FMS because you'll get wrong trim settings. So there goes the crosscheck with greendot or Vref!!!! So it is very much not SOP, thus very much not recommended. With a editable flex/ass temp, this crosscheck remains fully in charge, as the procedure is consistent with laptop program, FMS and loadsheet, thus perfectly legal and safe.
I would love a more flexible programm, with a more flexible SOP as to get TO performance. It would raise not only the pilots awareness, but just as much the safety level.
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Isn't there always someone who wants to rewrite the manual?
A 'wannabe' FOM or FSM?
I think Pool is one of these.
Just apply SOPs, Mate!
They were written by smarter people than you!
A 'wannabe' FOM or FSM?
I think Pool is one of these.
Just apply SOPs, Mate!
They were written by smarter people than you!
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Oh dear Obie, or should I write Odie?
A lot of noise and praise for the powers in charge, but no own analysis of the matter.
If any proposal of change or raising a question as to the viability of procedures concerning safety just creates your pathetic " ... follow the SOPs, they're written by smarter people than you ..." , then you have put yourself in a very low corner of aviation professionalism.
Just stay there and I hope we never meet in the real world ...... Mate!!
A lot of noise and praise for the powers in charge, but no own analysis of the matter.
If any proposal of change or raising a question as to the viability of procedures concerning safety just creates your pathetic " ... follow the SOPs, they're written by smarter people than you ..." , then you have put yourself in a very low corner of aviation professionalism.
Just stay there and I hope we never meet in the real world ...... Mate!!