Sackings at Emirates
Join Date: Oct 1999
Location: Adelaide
Posts: 668
Likes: 0
Received 0 Likes
on
0 Posts
Cerberus - while you are advocating the pious use of cliches, how about, as a professional pilot you are paid very handsomely to avoid the types of mistakes that kill 300 punters.
e28 driver
Join Date: Jan 2002
Location: UK
Posts: 211
Likes: 0
Received 0 Likes
on
0 Posts
SeldomFixit:
I get paid not very handsomely to avoid types of mistakes that would kill 30 punters. Do you really think level of pay makes a difference to the way one seeks to perform ones duty??
Level of pay may attract competant and qualified people to apply to a given airline, and then it is the job of that airlines recruitment system to select suitable candidates.
Assuming that an acceptable candidate is appointed and properly trained to the airlines procedures and equipment, should they then go on to make a mistake which endangers the lives of passengers, is it not a system failure which has allowed this?
Or is a fully qualified and trained person (who has hitherto satisfied all the company requirements to dispatch their assigned duties) who makes a mistake which endangers lives deemed to be 'negligent' and therefore liable to be terminated from employment, as most employment contracts make provision for?
I get paid not very handsomely to avoid types of mistakes that would kill 30 punters. Do you really think level of pay makes a difference to the way one seeks to perform ones duty??
Level of pay may attract competant and qualified people to apply to a given airline, and then it is the job of that airlines recruitment system to select suitable candidates.
Assuming that an acceptable candidate is appointed and properly trained to the airlines procedures and equipment, should they then go on to make a mistake which endangers the lives of passengers, is it not a system failure which has allowed this?
Or is a fully qualified and trained person (who has hitherto satisfied all the company requirements to dispatch their assigned duties) who makes a mistake which endangers lives deemed to be 'negligent' and therefore liable to be terminated from employment, as most employment contracts make provision for?
Union Goon
Join Date: Feb 2000
Location: New Jersey, USA
Posts: 1,097
Likes: 0
Received 0 Likes
on
0 Posts
CAP56,
that statements displays a shocking misunderstanding of how flex takeoff and runway data is used, and how much extra runway your really have.
Assuming that the pilots took off from the intersection and performed a flex takeoff with the right numbers for that intersection (and that the flex cap would not have been reached on full length), performance wise there is virtually no difference between taking off from an intersection and full length as long as appropriate flex numbers are used. Infact, once airborne, your climb and engine out performance would be better having gone from the intersection (though full power is always available, it is not figured into an engine failure scenario)
If your statement was "One does not flex ( or reduce thrust) on an 8 hour flight" then you might be improving safety for your leg of the flight (though probably reducing it somewhat for the next chap who flies your plane as you put more heat into the turbine, and driving up costs significantly for your airline) But a flex takeoff from an intersection or full length has pretty much the same margin for error. (again assuming that a flex cap wouldn;t have been reached on one takeoff instead of the other)
Flex thrust trades thrust for runway length effectively making the whole available runway required. Use a somewhat shorter runway length and more thrust is used. Use a longer runway and less thrust is used, but effectively froma pilots point of view, flex power is making every takeoff a maximum performance takeoff where a delayed rotation or abort after V1 will send you off the far end of the runway.
Cheers
Wino
I repeat my previous statement : "one does not T/O from an intersection on an 8 hr flight"
Assuming that the pilots took off from the intersection and performed a flex takeoff with the right numbers for that intersection (and that the flex cap would not have been reached on full length), performance wise there is virtually no difference between taking off from an intersection and full length as long as appropriate flex numbers are used. Infact, once airborne, your climb and engine out performance would be better having gone from the intersection (though full power is always available, it is not figured into an engine failure scenario)
If your statement was "One does not flex ( or reduce thrust) on an 8 hour flight" then you might be improving safety for your leg of the flight (though probably reducing it somewhat for the next chap who flies your plane as you put more heat into the turbine, and driving up costs significantly for your airline) But a flex takeoff from an intersection or full length has pretty much the same margin for error. (again assuming that a flex cap wouldn;t have been reached on one takeoff instead of the other)
Flex thrust trades thrust for runway length effectively making the whole available runway required. Use a somewhat shorter runway length and more thrust is used. Use a longer runway and less thrust is used, but effectively froma pilots point of view, flex power is making every takeoff a maximum performance takeoff where a delayed rotation or abort after V1 will send you off the far end of the runway.
Cheers
Wino
Re: not flexing for an 8 hour flight and intersection take offs.
I have it on very good authority that SIA are using almost max flex on t/o out of SIN on their A345's operating non-stop to LAX and that is a 16 hour flight. I believe that they will be using intersection W for departure out of EWR for take off on the south westerly runway when they start that service next week.
I have it on very good authority that SIA are using almost max flex on t/o out of SIN on their A345's operating non-stop to LAX and that is a 16 hour flight. I believe that they will be using intersection W for departure out of EWR for take off on the south westerly runway when they start that service next week.
Join Date: Jul 2000
Location: Dubai - sand land.
Age: 55
Posts: 2,832
Received 0 Likes
on
0 Posts
Cap 56. Being the expert that you are please tell me how much you understand of the PERF A requirements for modern transport aeroplanes.
ie - If the perf. calculations say you can take off from a particular intersection with a particular config and a particular flap setting than that is what you can do!!!!!!!!!!!!!!!!!!!!!!All you have to do is clear the end of the runway, sorry TODA by 35' (yes, 35' which is f**k all) with an engine out - or maybe 15', yes, FIFTEEN FEET on a wet runway, and you are completely LEGAL. It has nothing to do with how LONG the flight is
Moderators, moderate me if you want but this guy hasn't got a bl00dy clue
ie - If the perf. calculations say you can take off from a particular intersection with a particular config and a particular flap setting than that is what you can do!!!!!!!!!!!!!!!!!!!!!!All you have to do is clear the end of the runway, sorry TODA by 35' (yes, 35' which is f**k all) with an engine out - or maybe 15', yes, FIFTEEN FEET on a wet runway, and you are completely LEGAL. It has nothing to do with how LONG the flight is
Moderators, moderate me if you want but this guy hasn't got a bl00dy clue
Union Goon
Join Date: Feb 2000
Location: New Jersey, USA
Posts: 1,097
Likes: 0
Received 0 Likes
on
0 Posts
Furthermore white night,
unless you hit the flex cap (and then an airplane like the 777 lets you pile on derates as well as flex) you will clear the fence at the end of the runway by the exact same amount of clearence from the intersection of full length....
You are right, he has not a clue, atleast on this topic...
Cheers
Wino
unless you hit the flex cap (and then an airplane like the 777 lets you pile on derates as well as flex) you will clear the fence at the end of the runway by the exact same amount of clearence from the intersection of full length....
You are right, he has not a clue, atleast on this topic...
Cheers
Wino
Join Date: Dec 2002
Location: Inside an airplane
Posts: 58
Likes: 0
Received 0 Likes
on
0 Posts
EK JNB
Good rule, if you are conservative, the tower will always offer you the intersection. If you are close to the maximum take off weight, derated, flexible or not, go to the full length.
You will have that extra 150 meters or so not to hit the lights if anything goes wrong.
The wet V1 does not apply for the A-340 White Knight, we are discussing the EK JNB case.
Think about it.
Zeke
You will have that extra 150 meters or so not to hit the lights if anything goes wrong.
The wet V1 does not apply for the A-340 White Knight, we are discussing the EK JNB case.
Think about it.
Zeke
Union Goon
Join Date: Feb 2000
Location: New Jersey, USA
Posts: 1,097
Likes: 0
Received 0 Likes
on
0 Posts
Just to plays devils advocate,
If something goes wrong that requires TOGA power, if it is below V1, you probably should have stopped anyway, and if you are past v1 well... you will have more power already being made so the power change will be smaller minimizing the chance of inducing upset.
Furthermore some flex/derates are so massive as to have an enourmous effect on min V1 (which is a function of Vmc and Vmcg) so becarefull about taking 2 derates plus a flex (in a 777 this can cut an engine thrust almost in half) and then cobbing the engines. You may get a nasty suprise as you head off the side of the runway....
In principal, it is quite true that there is nothing quite so useless as runway behind you. But once you get into the regime of flex power (reduced thrust) takeoffs you are leaving MILES of runway behind you even if the aircraft starts from the physical end of the runway... So that old axiom doesn't really survive in the modern age.
HOWEVER, blasting down the runway in your C150 you bet. Use every inch of the runway. Its just that in jets you really leave your runway behind you when you dial in a flex number, not where you physically start rolling from...
Cheers
Wino
If something goes wrong that requires TOGA power, if it is below V1, you probably should have stopped anyway, and if you are past v1 well... you will have more power already being made so the power change will be smaller minimizing the chance of inducing upset.
Furthermore some flex/derates are so massive as to have an enourmous effect on min V1 (which is a function of Vmc and Vmcg) so becarefull about taking 2 derates plus a flex (in a 777 this can cut an engine thrust almost in half) and then cobbing the engines. You may get a nasty suprise as you head off the side of the runway....
In principal, it is quite true that there is nothing quite so useless as runway behind you. But once you get into the regime of flex power (reduced thrust) takeoffs you are leaving MILES of runway behind you even if the aircraft starts from the physical end of the runway... So that old axiom doesn't really survive in the modern age.
HOWEVER, blasting down the runway in your C150 you bet. Use every inch of the runway. Its just that in jets you really leave your runway behind you when you dial in a flex number, not where you physically start rolling from...
Cheers
Wino
Join Date: Dec 2002
Location: Inside an airplane
Posts: 58
Likes: 0
Received 0 Likes
on
0 Posts
JNB incident
It is easy to come with all this theory when you are sited behind a desk, but in the real world, when you are behind the controls of a big jet just about to take off, you better go to the extra mile. Always go to full length, you’ll never be sorry about that…
Zeke
Zeke
Join Date: Jul 2000
Location: Dubai - sand land.
Age: 55
Posts: 2,832
Received 0 Likes
on
0 Posts
Believe me, I always use the full length, however I'm merely pointing out PERF A requirements
If the book or the computer says you can do it then you can - remember there is a gross error percentage thrown into the figures for your protection.
Yes, going TOGA at lighter weights and lower speeds could give you a very bad day out....
If the book or the computer says you can do it then you can - remember there is a gross error percentage thrown into the figures for your protection.Yes, going TOGA at lighter weights and lower speeds could give you a very bad day out....
Join Date: Jan 2001
Location: UK
Posts: 2,044
Likes: 0
Received 0 Likes
on
0 Posts
Always go to full length, you’ll never be sorry about that…
when you are behind the controls of a big jet just about to take off,
If you take the
"ALWAYS SAFEST COURSE OF ACTION"
It's a difficult question - but there is nothing "unsafe" about using an intersection if the figures fit. The EK case seems so amazing (if the htpothesis is true) it should not affect that statement...
NoD
Join Date: Sep 2000
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
Dungfunnel,
I take great offence to your posting stating that "all us pretty girls are on the game". The majority of us being highly intelligent human beings who are merely here for the same reason as everyone else, to make money. Emirates is no better or worse than any other airline, we choose to be here and enjoy the 'false' lifestyle as you claim it be. Please sling your mud elsewhere.
I take great offence to your posting stating that "all us pretty girls are on the game". The majority of us being highly intelligent human beings who are merely here for the same reason as everyone else, to make money. Emirates is no better or worse than any other airline, we choose to be here and enjoy the 'false' lifestyle as you claim it be. Please sling your mud elsewhere.
Join Date: Jan 2004
Location: The World
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Emirates Sacking
What a load of waffle !!! Except the fact that the pilots made a fundamental error. You may blame the training department but rotating an aircraft to the desired attitude is basic. If you are going to operate different 340 variants, then prepare accordingly.
Taking off from an intersection using flex is irrelevant; in this case.
As for the 343 and 345 being fundamentally different, not true. I have flown both.
Gentleman the pilots concerned were lucky that their day ended as it did.
Taking off from an intersection using flex is irrelevant; in this case.
As for the 343 and 345 being fundamentally different, not true. I have flown both.
Gentleman the pilots concerned were lucky that their day ended as it did.
Join Date: Nov 2000
Location: Home
Posts: 903
Likes: 0
Received 0 Likes
on
0 Posts
Is it feasible that the performance calculations were made and set for the full length runway.
Then not readjusted for an intersection takeoff. If this was the case at a high elevation airport this would manifest itself as a considerable problem.
Then not readjusted for an intersection takeoff. If this was the case at a high elevation airport this would manifest itself as a considerable problem.
Union Goon
Join Date: Feb 2000
Location: New Jersey, USA
Posts: 1,097
Likes: 0
Received 0 Likes
on
0 Posts
STUDI,
I will try not to get too technical but derates and reduced power takeoffs are slightly different and can be used together in combination.
Generally for regulatory reasons, you cannot reduce thrust more than 25 percent as part of a flex power (reduced power) takeoff. So for round numbers we will use a 777 with 100,000lb thrust motors (pretty close to what AA has, I think the rolls royce engines are good for 94,000). So if you took the maximium reduction of thrust available (usual done as a simulated air temperature, we will say 70 dedgrees C but this part isn't important, just background info on how they do it)
So with a full flex at max rated power you could reduce engine output to 75,000 lbs of thrust per side which would reduce your turbine temps by several hundred degrees thereby prolonging engine life.
However, in doing so climb and cruise power on not effected and if climb power for the engine was say 75,000 lbs of thrust at sea level that is what you would get in the climb. and whatever the the cruise thrust is would still be unchanged.
But the 777 operates at an enourmous variation of weights and performance depenpending on whether you are going on a short hop like to England from JFK or to Narita from JFK.
So you have another option as well. These care called derates, usually labled 1 and 2 or something similar. The derates are a computer entry and trick the engines into thinking they are 90,000 lb thrust engines or 80,000 lb thrust engines. Once you do the derate to 80,000 lbs THEN you can flex 25 percent off of that and take the trust for takeoff all the way down to 60,0000lbs per side AND in this case climb and max cruise power will be reduced as well, thereby reducing heat across the entire operating spectrum of the engine.
Now remember that VMC and VMCG are basically a result of a ratio of the power of the engines to the strength of the rudder, That big rudder can overpower a much smaller engine thrust at a much lower speed. So you can have a lower permissable v1 at a lighter weight because the thrust will be lower so the aircraft won't roll over on its back or diverge from the runway. Suddenly cob the power though and you might have the 100,000lbs of thrust again below a speed which the rudder can counter it.
To really oversimplify it, basically all reduced power takeoffs are calculated so you wind up rotating on the far numbers. So you are lengthening your required runway so that you use every foot of runway as an acceleration area. The point I was making was that you will reach v1 and rotate in the same place pretty much regardless of where you started from on the runway. (yes I know that is an oversimplification for all you other nitpickers)
Again the rotate point would have been virtually the same because of the flex power takeoff so it wouldn't have mattered....
More runway won't fix this bad technique. The problem was they didn't rotate aggressively enough. The point at which they started the rotation would most likely not have changed appreciably.
One other thing that needs to be take into consideration from all you always go to the end of the runway people. Aircraft actually have taxi limitations on how far you can taxi them. (Most people aren't aware of them, but they exist because of sidewall heating that slow taxing generates. Its usually around a 35000 foot limit eg. 7 miles). While you won't reach them in most cases, take two laps around the orbit at kennedy or taxi to runway a very far runway in Denver and you most certainly will excede them.
as a further corrolarry to the above. Everyone thinks you wear tires on touch down with that impressive puff of smoke, but that is NOT where the tire wear occurs. 95 percent of tirewear occurs during taxi. So extra taxing could be heating your tires such that they will blow out when you try and stop....
One last thought, In this day and age of runway incursions going all the way to the end fo the runway just means you have to pass MORE intersections at a speed to fast to stop should someone else have their head down in their cockpit when it should be up...
Cheers
Wino
Edited to add:
Engineer. While very feasible and often a cause of such incidents, in this case it has been ruled out by the accident board I believe.
I will try not to get too technical but derates and reduced power takeoffs are slightly different and can be used together in combination.
Generally for regulatory reasons, you cannot reduce thrust more than 25 percent as part of a flex power (reduced power) takeoff. So for round numbers we will use a 777 with 100,000lb thrust motors (pretty close to what AA has, I think the rolls royce engines are good for 94,000). So if you took the maximium reduction of thrust available (usual done as a simulated air temperature, we will say 70 dedgrees C but this part isn't important, just background info on how they do it)
So with a full flex at max rated power you could reduce engine output to 75,000 lbs of thrust per side which would reduce your turbine temps by several hundred degrees thereby prolonging engine life.
However, in doing so climb and cruise power on not effected and if climb power for the engine was say 75,000 lbs of thrust at sea level that is what you would get in the climb. and whatever the the cruise thrust is would still be unchanged.
But the 777 operates at an enourmous variation of weights and performance depenpending on whether you are going on a short hop like to England from JFK or to Narita from JFK.
So you have another option as well. These care called derates, usually labled 1 and 2 or something similar. The derates are a computer entry and trick the engines into thinking they are 90,000 lb thrust engines or 80,000 lb thrust engines. Once you do the derate to 80,000 lbs THEN you can flex 25 percent off of that and take the trust for takeoff all the way down to 60,0000lbs per side AND in this case climb and max cruise power will be reduced as well, thereby reducing heat across the entire operating spectrum of the engine.
Now remember that VMC and VMCG are basically a result of a ratio of the power of the engines to the strength of the rudder, That big rudder can overpower a much smaller engine thrust at a much lower speed. So you can have a lower permissable v1 at a lighter weight because the thrust will be lower so the aircraft won't roll over on its back or diverge from the runway. Suddenly cob the power though and you might have the 100,000lbs of thrust again below a speed which the rudder can counter it.
It's absolutely clear that with applying reduced T/O hrust you reduce somehow your runway length
If the EK Crew really took off from an intersection it's a good example of having benefitted from more runway (no attack on the crew concerned, just to back-up my argument). They were sure they had it right, but even though they hit the end lights. More runway would have helped.
More runway won't fix this bad technique. The problem was they didn't rotate aggressively enough. The point at which they started the rotation would most likely not have changed appreciably.
One other thing that needs to be take into consideration from all you always go to the end of the runway people. Aircraft actually have taxi limitations on how far you can taxi them. (Most people aren't aware of them, but they exist because of sidewall heating that slow taxing generates. Its usually around a 35000 foot limit eg. 7 miles). While you won't reach them in most cases, take two laps around the orbit at kennedy or taxi to runway a very far runway in Denver and you most certainly will excede them.
as a further corrolarry to the above. Everyone thinks you wear tires on touch down with that impressive puff of smoke, but that is NOT where the tire wear occurs. 95 percent of tirewear occurs during taxi. So extra taxing could be heating your tires such that they will blow out when you try and stop....
One last thought, In this day and age of runway incursions going all the way to the end fo the runway just means you have to pass MORE intersections at a speed to fast to stop should someone else have their head down in their cockpit when it should be up...
Cheers
Wino
Edited to add:
Engineer. While very feasible and often a cause of such incidents, in this case it has been ruled out by the accident board I believe.
Join Date: Jun 2004
Location: not sure
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Is there any chance we can go back to the original chit chat about the sackings. This has all been said in the heading "JNB Incident" or have we all rambled on long enough.
Flygirl... I think you need to get outside a little more in the sun. If you take offence to dungfunnel's comments, then lets just close the whole pprune down, so that people like you that have had Totalatarian conditioning wont be offended by statements.
Flygirl... I think you need to get outside a little more in the sun. If you take offence to dungfunnel's comments, then lets just close the whole pprune down, so that people like you that have had Totalatarian conditioning wont be offended by statements.
Join Date: Sep 1999
Location: ME
Posts: 5,505
Likes: 0
Received 0 Likes
on
0 Posts
I’m sitting here laughing my head off with the number of Cessna pilots who believe they know how to operate commercial airliners. Flex/Assumed/Derated takeoffs combined with intersection takeoffs are an every day part of commercial aviation.
In the case of the EK JNB, the chances are that if they had used the full runway, they would have further decreased the amount of takeoff power, so at the end of the day, the result would be the same.
Mutt.
In the case of the EK JNB, the chances are that if they had used the full runway, they would have further decreased the amount of takeoff power, so at the end of the day, the result would be the same.
Mutt.