Rejecting A Takeoff After V1…why Does It (still) Happen?
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As I sit back with popcorn and chuckle, for those too ignorant to know, you're trying to match whits with a professional performance engineer (Mutt) who quite possibly knows more at this stage on the subject and is far more conversant about performance, safety, and requirements, than some of those arguing with him ever will be in their sorry lifetimes.
You guys sure know how to pick 'em. I wouldn't argue with Mutt regarding performance, because I know from the outset, I'd lose. Some of you are simply too stupid to understand that, so have fun beating your head against the wall.
Personally I'll have fun watching Galaxy Flyer and Mutt wipe the floor with you, when they're done. (Not that they haven't, already...)
You guys sure know how to pick 'em. I wouldn't argue with Mutt regarding performance, because I know from the outset, I'd lose. Some of you are simply too stupid to understand that, so have fun beating your head against the wall.
Personally I'll have fun watching Galaxy Flyer and Mutt wipe the floor with you, when they're done. (Not that they haven't, already...)
Like I said earlier, never argue with an idiot, they drag you down to their level, then beat you with experience.
Cessna has certainly messed things up with designations--two different planes, the old Citation 5, improved is a CE 560; as is a Citation XLS with an entirely different fuselage and engines. And 28 years since I last flew one, I can attend recurrent and and fly any of them. The TCDS is complicated to go through as any.
Just to clarify things, we are a private operator, we have a customized runway analysis for each take-off and remain within it's limits; we have a comprehensive ops manual and a SMS program. We try to operate to FAR 121 standards, to the extent of doing 3 page airport surveys before operating into a Cat B or Cat C field. I'd like to think other private operators are a conscientious about their operations, as we do not what to put others at risk.
Mutt. Better than that, he probably says he can do a non-stop return!
This thread has strayed far from a V1 discussion.
Cessna has certainly messed things up with designations--two different planes, the old Citation 5, improved is a CE 560; as is a Citation XLS with an entirely different fuselage and engines. And 28 years since I last flew one, I can attend recurrent and and fly any of them. The TCDS is complicated to go through as any.
Just to clarify things, we are a private operator, we have a customized runway analysis for each take-off and remain within it's limits; we have a comprehensive ops manual and a SMS program. We try to operate to FAR 121 standards, to the extent of doing 3 page airport surveys before operating into a Cat B or Cat C field. I'd like to think other private operators are a conscientious about their operations, as we do not what to put others at risk.
Mutt. Better than that, he probably says he can do a non-stop return!
This thread has strayed far from a V1 discussion.
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Mutt..I gave you my BEW and ZFW.
12200 ZFW - 9645 BEW = 2555 ZFW Payload
Based on last night winds..and some creative use of choosing certain power settings and the optimum alts....the trip was more then doable, considering all the places to stop between PDX and DAL....if the winds changed I probably would have stopped in Colo somewhere.
If your doing this on paper...shoot yourself now...your not going to be able to sit there, moving alts/power settings around to find and optimum combination that will keep you legal for take off, and have a legal reserve on the other end. Not in this lifetime that is.
12200 ZFW - 9645 BEW = 2555 ZFW Payload
Based on last night winds..and some creative use of choosing certain power settings and the optimum alts....the trip was more then doable, considering all the places to stop between PDX and DAL....if the winds changed I probably would have stopped in Colo somewhere.
If your doing this on paper...shoot yourself now...your not going to be able to sit there, moving alts/power settings around to find and optimum combination that will keep you legal for take off, and have a legal reserve on the other end. Not in this lifetime that is.
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safetypee . . .
"...Technology has and still continues to improve reliability, thus the human in comparison appears the weaker link."
GB, “Technology has and still continues to improve reliability, …”
Perhaps of interest / relevance in this thread, is that Trent engine did not go ‘bang’ during takeoff, often assumed to be the most critical period.
“The human in comparison appears the weaker link." - Context. An essential component of awareness and understanding the problem, which I assume you already know …
This does not detract from the excellent talent and skills of the crew, which IMHO argues strongly for the human to remain in the loop during critical tasks. We Still Need Exceptional People.
However, humans do have limitations, especially in high stress, time-critical tasks. The Qantas crew had time and managed it, and other resources very well.
In critical instances such as a high speed RTO we should review the tasks which we ask of the crew. We could better match the task to actual capability (as indicated by accident reports) and not necessarily persevere with assumed human performance based primarily on engine failures during takeoff (possibly in older / slower aircraft), particularly where nowadays engine failures are less frequent.
Perhaps of interest / relevance in this thread, is that Trent engine did not go ‘bang’ during takeoff, often assumed to be the most critical period.
“The human in comparison appears the weaker link." - Context. An essential component of awareness and understanding the problem, which I assume you already know …
This does not detract from the excellent talent and skills of the crew, which IMHO argues strongly for the human to remain in the loop during critical tasks. We Still Need Exceptional People.
However, humans do have limitations, especially in high stress, time-critical tasks. The Qantas crew had time and managed it, and other resources very well.
In critical instances such as a high speed RTO we should review the tasks which we ask of the crew. We could better match the task to actual capability (as indicated by accident reports) and not necessarily persevere with assumed human performance based primarily on engine failures during takeoff (possibly in older / slower aircraft), particularly where nowadays engine failures are less frequent.
Moderator
Like I said earlier, never argue with an idiot, they drag you down to their level, then beat you with experience.
Sometimes I think I am far too tolerant. Tidied up a few posts .. hopefully we can get back to rational and pertinent discussion ...
Sometimes I think I am far too tolerant. Tidied up a few posts .. hopefully we can get back to rational and pertinent discussion ...
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Actually John...your tolerant to the same 4 trolls in here, and ban the people they jump on for fun.....if you want to fix these problems might I suggest you reign in the obvious trouble makers..
If your just about making friends and not promoting any serious discussion on aviation...put that on the banner, I won't come back....
I think your guise as a wise and tolerant moderator is a pretty thin veneer.
Sincerely,
Johns, SSG, ect....
If your just about making friends and not promoting any serious discussion on aviation...put that on the banner, I won't come back....
I think your guise as a wise and tolerant moderator is a pretty thin veneer.
Sincerely,
Johns, SSG, ect....
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your tolerant to the same 4 trolls
You would be more than welcome to share these pages (speaking for myself) if you didn't carry on with the Walter Mitty story telling. You bluff no one who has any aviation credentials, and may in fact be something of a safety hazard by influencing an audience who don't have the background to be able to sort the wheat from the chaff.
not promoting any serious discussion on aviation
I think your guise as a wise and tolerant moderator is a pretty thin veneer
might I suggest you reign in the obvious trouble makers
Should you have a change in heart as to how you engage you will find the community here welcoming with open arms and with a very warm embrace.
Peace be with you.
Sincerely,
Brian
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Brian Abraham:
Your message is well stated for the most part, and in particular about John. But, I believe good engagement in this forum doesn't necessarily result in very warm open arms.
Should you have a change in heart as to how you engage you will find the community here welcoming with open arms and with a very warm embrace.
An RTO question:-
Is there any data for RTOs which resulted in serious incidents or accidents, particularly those commenced above V1, indicating other contributory / external factors, i.e. less than the recommended overrun distance / area.
The line of thought is that if an ‘overrun’ is contained in a safety area without major damage, then these may not appear in accident statistics and thus hide a potentially higher rate of high speed RTOs – incorrect decision but successful outcome.
Conversely how many incidents became accidents because of systematic failures; the crew decision (> V1) might only have been the initiating contribution.
The line of thought is that if an ‘overrun’ is contained in a safety area without major damage, then these may not appear in accident statistics and thus hide a potentially higher rate of high speed RTOs – incorrect decision but successful outcome.
Conversely how many incidents became accidents because of systematic failures; the crew decision (> V1) might only have been the initiating contribution.
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For someone operating a single pilot jet that requires a 5,000 ft ASD from a 10,000 ft runway, there is some logic in deciding to abort on the runway prior to VLOF rather than take flight following an engine failure or some other serious malfunction, especially considering the work load for a single pilot.... however, where do you draw the line, are you willing to do the same on a 9,000 ft runway or even a 7,000 ft runway? In order for you to make a rational decision, you should know what version of FAR 25-109 your aircraft was certified under, the brake condition, and even the calculations methodology used for the AFM.
When you move into the airline world or even the larger corporate world, things change, the aircraft that you fly are designed to operate in the most economical manner possible, you may fly different variants of the same family, (A320/321)(A330/340), there is no possible way that you can know the different characteristics associated with each tail number or runway. But you should be aware if your airline has adopted a Min or Max V1 or optimized V-speeds policy and the reduced thrust policy?
When the people sitting in some dark office decided how these aircraft were going to be operated, they had days or even months to review all of the related facts, to look at in-depth details about the aircraft's performance, the airport, the runway condition and in some cases they have even walked the runway to ensure that the data is correct. For more obscure runways they may have flight tested the departure profiles in a real Flight Simulator, or flown test flights into the airport. The result of all that work is given to the crew on one sheet of paper, it gives a limiting take-off weight at a specific temperature/pressure/wind and it gives V-speeds.
With the aim of reducing high speed rejected takeoff's and enhancing safety. The industry evolved into being more "Go Minded", V1 changed from being a "Decision Speed" into a "Action Speed", a training aid called the Boeing Takeoff Safety guide was released circa 1991 to educate people about RTO's and the correct methods to be used during an RTO. Its worth reading...
Some may ask you to second guess the decision to reject once above V1, but surely if this was the safest option, then in the last 20 years since the formation of the Boeing Takeoff Safety group, then the teaching methods would have changed!
As a final note, As these are anonymous forums the origins of the contributions may be opposite to what may be apparent. In fact the press may use it, or the unscrupulous, or sciolists*, to elicit certain reactions.
Mutt
When you move into the airline world or even the larger corporate world, things change, the aircraft that you fly are designed to operate in the most economical manner possible, you may fly different variants of the same family, (A320/321)(A330/340), there is no possible way that you can know the different characteristics associated with each tail number or runway. But you should be aware if your airline has adopted a Min or Max V1 or optimized V-speeds policy and the reduced thrust policy?
When the people sitting in some dark office decided how these aircraft were going to be operated, they had days or even months to review all of the related facts, to look at in-depth details about the aircraft's performance, the airport, the runway condition and in some cases they have even walked the runway to ensure that the data is correct. For more obscure runways they may have flight tested the departure profiles in a real Flight Simulator, or flown test flights into the airport. The result of all that work is given to the crew on one sheet of paper, it gives a limiting take-off weight at a specific temperature/pressure/wind and it gives V-speeds.
With the aim of reducing high speed rejected takeoff's and enhancing safety. The industry evolved into being more "Go Minded", V1 changed from being a "Decision Speed" into a "Action Speed", a training aid called the Boeing Takeoff Safety guide was released circa 1991 to educate people about RTO's and the correct methods to be used during an RTO. Its worth reading...
Some may ask you to second guess the decision to reject once above V1, but surely if this was the safest option, then in the last 20 years since the formation of the Boeing Takeoff Safety group, then the teaching methods would have changed!
As a final note, As these are anonymous forums the origins of the contributions may be opposite to what may be apparent. In fact the press may use it, or the unscrupulous, or sciolists*, to elicit certain reactions.
Mutt
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Let me translate that for you Mutt....for clarity sake...
'When you fly corporate the boss is sitting in the back with his family, he doesn't want his pilot driving the plane to the fence and pulling it off...but when you fly for the airlines, and the flying public has no clue as to how a plane should be flown...it's ok to burn up all the runway with reduced power take offs, because when you bring the plane back to the shop, your own mechanics, who are compelled to stretch the engine overhaul times out as far as possible, can have an easier time not seeing things in the boroscope during the inspection process.
It's all about having enough insurance for each passenger seat, vs paying for more engines, and if you hire cheap pilots, who believe that burning up runway on purpose make sense, in some alternate reality, they can walk up and down the aisle telling the passengers, that safety is first, and actually believe it.."
'When you fly corporate the boss is sitting in the back with his family, he doesn't want his pilot driving the plane to the fence and pulling it off...but when you fly for the airlines, and the flying public has no clue as to how a plane should be flown...it's ok to burn up all the runway with reduced power take offs, because when you bring the plane back to the shop, your own mechanics, who are compelled to stretch the engine overhaul times out as far as possible, can have an easier time not seeing things in the boroscope during the inspection process.
It's all about having enough insurance for each passenger seat, vs paying for more engines, and if you hire cheap pilots, who believe that burning up runway on purpose make sense, in some alternate reality, they can walk up and down the aisle telling the passengers, that safety is first, and actually believe it.."
