EK407 Tailstrike @ ML
Not quite so simple Framer........
Slightly off thread I know, but when learning to navigate I was told to stop trying to do a maths exam in a rattling steel cabinet and pretend I was sat on the tail driving the thing over a map of the World, but it is the same thing with take off performance, if you are going a long way you will be heavy, EPR numbers and V1/V2 numbers will be BIGGER. If they're not, stop and ask why. Might be a perfectly good reason, but might not, also.
I believe the SQ incident out of AKL was being flown by a guy recently off the A 340, so the lower numbers that they had mistakenly derived, seemed OK to him, had he been more familiar with the 747 he wouldn't have accepted them. The Big Picture. Head out of the computer. ( I also vowed I'd never fly without a Flight Engineer, too - but that's another story !! )
Join Date: Jan 2002
Location: UK
Posts: 158
Likes: 0
Received 0 Likes
on
0 Posts
Regarding flex/derate/assumed take off:
You cite best industry practice. Well, it's not completely true. With the EK software, you can only go for full thrust or max reduction. Any in-between, which is used a lot elsewhere for a little more safety margin but not full thrust, is not recommedable here, because the gross error trapping procedure a la EK will no longer be possible. It's not in the SOP, so either full or full reduction, which I believe is not best practice.
You cite best industry practice. Well, it's not completely true. With the EK software, you can only go for full thrust or max reduction. Any in-between, which is used a lot elsewhere for a little more safety margin but not full thrust, is not recommedable here, because the gross error trapping procedure a la EK will no longer be possible. It's not in the SOP, so either full or full reduction, which I believe is not best practice.
Why?
Join Date: Jul 2000
Location: Dubai - sand land.
Age: 55
Posts: 2,832
Received 0 Likes
on
0 Posts
Exsp33dbird - The whole point is that there isn't such a simple 'ballpark' figure on this aeroplane.. With the 'coming' of the laptop optimiser the tables with the 'about right' figures went out of the window
One day you can put in the figures and get a flap 3 take-off, the next day same sector and a couple of minor variables and you've got a 1+F setting - and all with differing flex and speed settings. The performance is OPTIMISED - unlike my last type which had set speeds for set flaps at set weights..
There is no planned EPR setting as such either with the RR Trents on this aircraft. You put the calculated flex into the PERF page and let the FADEC work out how much EPR to set... Again - no ballpark as such..
One day you can put in the figures and get a flap 3 take-off, the next day same sector and a couple of minor variables and you've got a 1+F setting - and all with differing flex and speed settings. The performance is OPTIMISED - unlike my last type which had set speeds for set flaps at set weights..
There is no planned EPR setting as such either with the RR Trents on this aircraft. You put the calculated flex into the PERF page and let the FADEC work out how much EPR to set... Again - no ballpark as such..
Join Date: Jul 2000
Location: Dubai - sand land.
Age: 55
Posts: 2,832
Received 0 Likes
on
0 Posts
And just to further clarify - the Green Dot check is the check that should save your bacon. The Green Dot speed on the PERF page is calculated by the FMS from the ZFW and fuel load inserted into the INIT B.
When the laptop calc is complete the Green Dot speed shown on the 'perf' screen should be within a couple of knots.. If its not then ask questions..
Clear??
When the laptop calc is complete the Green Dot speed shown on the 'perf' screen should be within a couple of knots.. If its not then ask questions..
Clear??
Forgive me White Knight but can you confirm for me how much Vr would change for say 360T and Flap 3 for zero degrees celcius through to 35 degrees celcius ambiant. So really what I am asking is 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.
Thanks for taking the time,
framer
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.
Thanks for taking the time,
framer
Join Date: Jan 2005
Location: W of 30W
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
Also White Knight, as you seem to be current on this Airbus type, would you provide us with some more data ?
The report didn't elaborate much except that at a TOW of 263 tonnes as wrongly inserted into the laptop :
Please, what should have been these figures if the correct TOW of 363 tonnes had been inserted ?
The report didn't elaborate much except that at a TOW of 263 tonnes as wrongly inserted into the laptop :
- Vr was 147 kt
- FLEX was 74C
- CONF was 1+F
Please, what should have been these figures if the correct TOW of 363 tonnes had been inserted ?
Join Date: Jul 2000
Location: Dubai - sand land.
Age: 55
Posts: 2,832
Received 0 Likes
on
0 Posts
I'd need access to a laptop and as I'm off work for a few days I'll have to get back to you.......
All I can say is that at 360 tonnes you will NOT get a flex of 74 degrees. However you MAY get 1+F.. I also think that the V2 is a BETTER gross error check than Vr.
All I can say is that at 360 tonnes you will NOT get a flex of 74 degrees. However you MAY get 1+F.. I also think that the V2 is a BETTER gross error check than Vr.
Join Date: Jan 2005
Location: W of 30W
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
Thanks, I appreciate.
I agree for the V2, but I haven't seen any reference on that one in the report ?
V1 is positively given : 143
Vr is indirectly mentioned : 147 ?
Vr is also of interest regarding the tailstrike aspect.
And of course the FLEX ...
Anyway, no rush, fully enjoy your days off first !
I agree for the V2, but I haven't seen any reference on that one in the report ?
V1 is positively given : 143
Vr is indirectly mentioned : 147 ?
Vr is also of interest regarding the tailstrike aspect.
And of course the FLEX ...
Anyway, no rush, fully enjoy your days off first !
White Knight - thank you, I guess one retires for a good reason ! But does 'progress' always improve things ? The tried and true KISS method ( Keep It Simple Stupid ) saved a lot of disasters.
I recall one of my Nav. instructors telling me that I'd never make a navigator until I'd been over Berlin with the shells coming through the cockpit whilst I was trying to get a 3-wind drift reading through a drift-sight ! Of course I never had to, similarly my future students never had to cope with trying to get a Sun, Moon, Venus sextant fix on a daylight Atlantic crossing when the Loran reception was down, and I despaired as they struggled with it for practice - INS was their Brave New World, now of course superceded by GPS.
But ...... the Big Picture is still important, I once had a co-pilot try to steer me NorthWest to Australia from Singapore - he had cocked up his maths / INS / FMS inputs and come up with a heading of 315 deg. The Big Picture again.
Whilst instructing for an Asian airline our students were very able instrument pilots, brought up on a diet of Space Invader and Microsoft games, but initially had difficulty connecting a real aeroplane to the real Earth. One of my colleagues remarked how the World had turned full circle, when we were flying with the old (?) WW II bomber pilots, many had difficulty following an instrument approach, but pop out of cloud, too high, too fast, not in line, not configured etc. etc. and point out the runway through the side window even, and they would immediately settle down and perform an immaculate visual approach and landing.
Horses for Courses, I guess. I hope you enjoy your aviation career as much as I enjoyed mine - and still do, albeit single seat microlights ( I still miss the Flt.Eng tho' !!! )
Cheers, ExSp33db1rd
I recall one of my Nav. instructors telling me that I'd never make a navigator until I'd been over Berlin with the shells coming through the cockpit whilst I was trying to get a 3-wind drift reading through a drift-sight ! Of course I never had to, similarly my future students never had to cope with trying to get a Sun, Moon, Venus sextant fix on a daylight Atlantic crossing when the Loran reception was down, and I despaired as they struggled with it for practice - INS was their Brave New World, now of course superceded by GPS.
But ...... the Big Picture is still important, I once had a co-pilot try to steer me NorthWest to Australia from Singapore - he had cocked up his maths / INS / FMS inputs and come up with a heading of 315 deg. The Big Picture again.
Whilst instructing for an Asian airline our students were very able instrument pilots, brought up on a diet of Space Invader and Microsoft games, but initially had difficulty connecting a real aeroplane to the real Earth. One of my colleagues remarked how the World had turned full circle, when we were flying with the old (?) WW II bomber pilots, many had difficulty following an instrument approach, but pop out of cloud, too high, too fast, not in line, not configured etc. etc. and point out the runway through the side window even, and they would immediately settle down and perform an immaculate visual approach and landing.
Horses for Courses, I guess. I hope you enjoy your aviation career as much as I enjoyed mine - and still do, albeit single seat microlights ( I still miss the Flt.Eng tho' !!! )
Cheers, ExSp33db1rd
Join Date: Jun 2001
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
I have to plead guilty not to having read in full all of the last few pages of posts, as many of them seem at first glance to be attempting to come up with plans of varying usefullness to avoid a repetition of exactly the same situation that the crew of EK407 encountered that fateful evening.
Shoot me down in flames if what follows deserves it, but I believe the ATSB report will come out with recommendations that look beyond this 'shut the stable door behind the bolted horse' approach. It's been said before, but I believe it's worth repeating: no one out there - at least no one who holds an ATPL (I hope that's not too cryptic for most Sandpit readers) - believes for one moment that the crew set out that night not to follow SOPS.
(Again, as someone has said before me), one of the more likely findings will be that they were interrupted during some stage of their crosschecking and (perhaps, in some readers' opinion, unforgivably) neglected to go back and re-do the procedure from the beginning.
With that (as yet unconfirmed) scenario in mind, perhaps we should be looking at 'a fix' that covers more pitfalls than just the one this particular crew encountered. Maybe a sterile cockpit (i.e., a locked cockpit door) during the three or four minutes that the initial briefing and preparation of takeoff figures are done?
Anyone with five sectors of line experience will know it's highly impractical to suggest this sterile cockpit could be imposed later in the pre-departure sequence (i.e., the twenty-five minutes leading up to pushback). However, it, or something along similar lines, might be worth considering earlier in the pre-departure sequence, immediately after the crew have set themselves up and the tech log review and the walkaround have been completed.
I know the final ZFW will not have arrived at that stage, and therefore the crew will not be able to come up with accurate RTOW figures, and I know a late runway change will throw such preparations even further out. However, using the expected takeoff figures would give the crew a ballpark figure arrived at in a relatively non threatening situation that could be compared with the final figures for a gross error check - and, perhaps even more importantly, it would allow a proper takeoff briefing to be conducted without interruption.
People far smarter than I am will come up with something, probably far more clever than what I've suggested above. I just hope it's something a little more all-encompassing than the knee-jerk procedure we've come up after EK407 that covers only the particular pitfall that caught out that crew.
I believe there'd be few line pilots who would not say that there are many more pitfalls out there waiting to catch out some other crew in the future, and many such pitfalls could be 'trapped' far earlier than they are by crews today if we reduced the interruptions and distractions crews endure as they do their takeoff preparations under the present set up.
Shoot me down in flames if what follows deserves it, but I believe the ATSB report will come out with recommendations that look beyond this 'shut the stable door behind the bolted horse' approach. It's been said before, but I believe it's worth repeating: no one out there - at least no one who holds an ATPL (I hope that's not too cryptic for most Sandpit readers) - believes for one moment that the crew set out that night not to follow SOPS.
(Again, as someone has said before me), one of the more likely findings will be that they were interrupted during some stage of their crosschecking and (perhaps, in some readers' opinion, unforgivably) neglected to go back and re-do the procedure from the beginning.
With that (as yet unconfirmed) scenario in mind, perhaps we should be looking at 'a fix' that covers more pitfalls than just the one this particular crew encountered. Maybe a sterile cockpit (i.e., a locked cockpit door) during the three or four minutes that the initial briefing and preparation of takeoff figures are done?
Anyone with five sectors of line experience will know it's highly impractical to suggest this sterile cockpit could be imposed later in the pre-departure sequence (i.e., the twenty-five minutes leading up to pushback). However, it, or something along similar lines, might be worth considering earlier in the pre-departure sequence, immediately after the crew have set themselves up and the tech log review and the walkaround have been completed.
I know the final ZFW will not have arrived at that stage, and therefore the crew will not be able to come up with accurate RTOW figures, and I know a late runway change will throw such preparations even further out. However, using the expected takeoff figures would give the crew a ballpark figure arrived at in a relatively non threatening situation that could be compared with the final figures for a gross error check - and, perhaps even more importantly, it would allow a proper takeoff briefing to be conducted without interruption.
People far smarter than I am will come up with something, probably far more clever than what I've suggested above. I just hope it's something a little more all-encompassing than the knee-jerk procedure we've come up after EK407 that covers only the particular pitfall that caught out that crew.
I believe there'd be few line pilots who would not say that there are many more pitfalls out there waiting to catch out some other crew in the future, and many such pitfalls could be 'trapped' far earlier than they are by crews today if we reduced the interruptions and distractions crews endure as they do their takeoff preparations under the present set up.
Join Date: May 2008
Location: pit
Posts: 314
Likes: 0
Received 0 Likes
on
0 Posts
A lot of good ideas, technical goodies etc., but I'd go with Wileys arguments. However, I proposed another approach as to how to proceed, and I still stick to my arguments.
1. Any action done alone needs to be confirmed by the fellow crew member(s). So why do it in the first place? To eliminate error? To crosscheck? I do not believe that such procedures are superior in trapping errors, as BOTH individualists might make errors, eventually doubling the risk. We are a team after all, aren't we?
2. Anything done in advance is by definition imprecise, as not all values are yet known. So why do it then? To give us a preliminary picture? To raise awareness? I do not believe that this helps trapping errors. I believe it might even set a trap, as it preconceives our thinking. It might lead to the feeling " ... it has already been covered".
As a consequence to these two arguments, I prefer working as follows:
Do all the math on the flightplan, as usual. We can crosscheck that, to raise awareness, big picture. Wait for the TO calculations until receipt of the loadsheet. Then go through it TOGETHER. Note the values on the flpl. Go into the laptop/EFB/charts, with the ACTUAL VALUES. Once the result shows, insert the necessary values into the FMC, set the MCP/FCP. All this done TOGETHER, do a quick CROSSCHECK a): loadsheet vs. FMC (grossweight), and a second crosscheck b): FMC vs. laptop/EFB/chart (greendot/Vref30).
This should take no more than three minutes, during which the crew may throw everybody out of the cockpit. Additionally such a procedure can be applied with anything from two to one laptops/EFBs, any kind of charts and even a precalculated ACARS from dispatch.
KISS
1. Any action done alone needs to be confirmed by the fellow crew member(s). So why do it in the first place? To eliminate error? To crosscheck? I do not believe that such procedures are superior in trapping errors, as BOTH individualists might make errors, eventually doubling the risk. We are a team after all, aren't we?
2. Anything done in advance is by definition imprecise, as not all values are yet known. So why do it then? To give us a preliminary picture? To raise awareness? I do not believe that this helps trapping errors. I believe it might even set a trap, as it preconceives our thinking. It might lead to the feeling " ... it has already been covered".
As a consequence to these two arguments, I prefer working as follows:
Do all the math on the flightplan, as usual. We can crosscheck that, to raise awareness, big picture. Wait for the TO calculations until receipt of the loadsheet. Then go through it TOGETHER. Note the values on the flpl. Go into the laptop/EFB/charts, with the ACTUAL VALUES. Once the result shows, insert the necessary values into the FMC, set the MCP/FCP. All this done TOGETHER, do a quick CROSSCHECK a): loadsheet vs. FMC (grossweight), and a second crosscheck b): FMC vs. laptop/EFB/chart (greendot/Vref30).
This should take no more than three minutes, during which the crew may throw everybody out of the cockpit. Additionally such a procedure can be applied with anything from two to one laptops/EFBs, any kind of charts and even a precalculated ACARS from dispatch.
KISS
The LPC user interface is riddled with ways in which to screw up.
Even more so when it comes to non-standard inputs; modified runway lengths or failures.
Whenever I fire up the LPC I always enter the airfield data as soon as I start it and run the perf for MTOW, for 2 reasons. Firstly it gives me situational awareness, it gives me an idea of the speeds, flex and what weight we can lift of the runway in question, and secondly if for some reason I then forget to re-enter correct weight when we get the final then we are covered as we have the most conservative figures possible.
The way I do is not SOP, just a technique, and I know that there is no foolproof way but it works for me.
Even more so when it comes to non-standard inputs; modified runway lengths or failures.
Whenever I fire up the LPC I always enter the airfield data as soon as I start it and run the perf for MTOW, for 2 reasons. Firstly it gives me situational awareness, it gives me an idea of the speeds, flex and what weight we can lift of the runway in question, and secondly if for some reason I then forget to re-enter correct weight when we get the final then we are covered as we have the most conservative figures possible.
The way I do is not SOP, just a technique, and I know that there is no foolproof way but it works for me.
Join Date: May 2005
Location: Mars
Posts: 527
Likes: 0
Received 0 Likes
on
0 Posts
Confiture,
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.
I guess a problem the industry faces is that operations have come so routine. When I am sitting on a 340 with the other guy flying at heavy weight and call rotate nothing much happens initially because the jet is so heavy, going so quick and has so much inertia. I still find that startling, many of our colleagues do not and we have to shake the complacency that comes with our routine operations and look for trouble.
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.
I guess a problem the industry faces is that operations have come so routine. When I am sitting on a 340 with the other guy flying at heavy weight and call rotate nothing much happens initially because the jet is so heavy, going so quick and has so much inertia. I still find that startling, many of our colleagues do not and we have to shake the complacency that comes with our routine operations and look for trouble.
Join Date: Apr 2008
Location: Sand on the Rocks !
Age: 41
Posts: 111
Likes: 0
Received 0 Likes
on
0 Posts
In the 737s, we use an "unofficial" thumb rule to check the figures.
The 1st 2 digits of your ATOW [from trim sheet] - 20 gives the V2 +- 3 knots.
For eg, if ATOW = 70,000 Kgs, then V2 would be [70-20] = 150 +- 2 knots. This can be used as a fairly accurate cross-check on whether you entered the figures in the FMC correctly or not. Maybe the 340 also has a thumb rule like this
Cheers
The 1st 2 digits of your ATOW [from trim sheet] - 20 gives the V2 +- 3 knots.
For eg, if ATOW = 70,000 Kgs, then V2 would be [70-20] = 150 +- 2 knots. This can be used as a fairly accurate cross-check on whether you entered the figures in the FMC correctly or not. Maybe the 340 also has a thumb rule like this
Cheers