Litigation.
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Litigation.
On another topic we broached the subject of litigation in relation to post takeoff accidents. We are talking about operating an aircraft within its certification limits, having an engine failure 1 second before V1, doing everything by the book and still running off the end of the runway.
Is the crew still responsible?
Mutt
Is the crew still responsible?
Mutt
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Mutt---
Well, the Greeks sure seem to think so. Recall a TMA B747 aborted and ran off the end of 33R in ATH in 1974. The Captain was arrested I believe and held for around 2 days in the slammer. As it was a cargo flight he was released as no damage was done to anything else other than the aircraft.
And, let us not forget SR, landed long on 15L (ATH again) and overran, the Captain was arrested.
BEWARE of Greek jurisprudence.
Well, the Greeks sure seem to think so. Recall a TMA B747 aborted and ran off the end of 33R in ATH in 1974. The Captain was arrested I believe and held for around 2 days in the slammer. As it was a cargo flight he was released as no damage was done to anything else other than the aircraft.
And, let us not forget SR, landed long on 15L (ATH again) and overran, the Captain was arrested.
BEWARE of Greek jurisprudence.
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Yes !
Thats why they pay you the money, give you the title and let you wear the(gold) braid.
Of course should you ever be so unfortunate as to be involved in litigation as a result of your obligations, then the responsibility will be decided by the Judge and or jury.
Thats why they pay you the money, give you the title and let you wear the(gold) braid.
Of course should you ever be so unfortunate as to be involved in litigation as a result of your obligations, then the responsibility will be decided by the Judge and or jury.
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Mutt,
The short answer is yes. If you only recognise the failure at V1, then its a go and sort it out airborne.
V1 was redefined by both the FAA in February 1988 and JAA in March 1988 as the maximum airspeed at which a flight crew must take the first action to safely reject a takeoff, not the recognition of the failure.
Inconsistent terminology has caused confusion about the V1 concept. An important assumption in the V1 concept today is that the decision to continue the takeoff or reject the takeoff is made before reaching V1. The accelerate-stop performance data in AFM/POH/FCOM are based on the pilot flying taking the first action to reject the takeoff at V1.
For airplane-certification purposes, the actions required to reject a takeoff include applying the wheel brakes, reducing thrust, and deploying the speed brakes or spoilers. The manufacturer establishes the order in which these actions are taken.
What the rules say ...
The recognition of the failure should occur at V1-(3 to 5 kt) to give the crew time to react. Before 1978, manufacturers were required to adjust accelerate-stop distances to allow for two seconds of airplane travel require that manufacturers add the distance equivalent to two seconds (one second between the first and second actions to reject the takeoff, and one second between the second and third actions)at the V1 speed.
People have come to use “soft V1” calls at V1-(3-5) kts, so the hands come off the throttle quadrant just before the airspeed needle passes the V1 bug speed.
Z
P.S. If you hurt someone in the process of a high speed reject you may go to jail for negligence or manslaughter, if you bend the aircraft you may end up work the rest of your life to pay the insurance company back for operating the aircraft not to the AFM/POH/FCOM.
Do they still do public stoning in the middle east Mutt ?
On the bright side, Boeing projects one RTO in every 3,000 takeoffs and one high-speed RTO in every 150,000 takeoffs. Airbus numbers are higher (newer airframes and engines).
The short answer is yes. If you only recognise the failure at V1, then its a go and sort it out airborne.
V1 was redefined by both the FAA in February 1988 and JAA in March 1988 as the maximum airspeed at which a flight crew must take the first action to safely reject a takeoff, not the recognition of the failure.
Inconsistent terminology has caused confusion about the V1 concept. An important assumption in the V1 concept today is that the decision to continue the takeoff or reject the takeoff is made before reaching V1. The accelerate-stop performance data in AFM/POH/FCOM are based on the pilot flying taking the first action to reject the takeoff at V1.
For airplane-certification purposes, the actions required to reject a takeoff include applying the wheel brakes, reducing thrust, and deploying the speed brakes or spoilers. The manufacturer establishes the order in which these actions are taken.
What the rules say ...
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People have come to use “soft V1” calls at V1-(3-5) kts, so the hands come off the throttle quadrant just before the airspeed needle passes the V1 bug speed.
Z
P.S. If you hurt someone in the process of a high speed reject you may go to jail for negligence or manslaughter, if you bend the aircraft you may end up work the rest of your life to pay the insurance company back for operating the aircraft not to the AFM/POH/FCOM.
Do they still do public stoning in the middle east Mutt ?
On the bright side, Boeing projects one RTO in every 3,000 takeoffs and one high-speed RTO in every 150,000 takeoffs. Airbus numbers are higher (newer airframes and engines).
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From a practical viewpoint, Boeing, in training material, suggests very strongly that, if the aircraft is not in the process of being stopped by V1 .. then you ought to continue in a limiting accel stop situation. Allowing for the normal liability considerations, I read that to infer a very definite advice to go, rather than stop, other things being equal, as one approaches V1.
I still have a very real concern when people keep talking about takeoff performance like it is all black and white. Shades of grey need considered thought on a take off by take off basis by the crew to assess what might be a good application of the procedures on any given occasion. Such consideration necessarily must lean very heavily on flight manual and company operations manual guidance.
I still have a very real concern when people keep talking about takeoff performance like it is all black and white. Shades of grey need considered thought on a take off by take off basis by the crew to assess what might be a good application of the procedures on any given occasion. Such consideration necessarily must lean very heavily on flight manual and company operations manual guidance.
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JT,
If the question is posed about an isolated engine failure at V1, I think its a go decision.
Our training and drills are well rehearsed and the outcome of emergencies are predetermined in many cases. Variations to the procedures or manuals is of course up to the crew, you would want to have an absolute basis for any variation.
The number of people who have had high speed rejected takeoffs and write the aircraft off and injure people in the process is alarming, subsequent analysis has shown no need for the reject.
Reasonable people like pilots and engineers talk and think in colors and shades of gray....what if this, I thought this, I felt this, I heard this.....at the end of the day the Lawyers and Jurnos talk in Black and White...Pilot error
Z
If the question is posed about an isolated engine failure at V1, I think its a go decision.
Our training and drills are well rehearsed and the outcome of emergencies are predetermined in many cases. Variations to the procedures or manuals is of course up to the crew, you would want to have an absolute basis for any variation.
The number of people who have had high speed rejected takeoffs and write the aircraft off and injure people in the process is alarming, subsequent analysis has shown no need for the reject.
Reasonable people like pilots and engineers talk and think in colors and shades of gray....what if this, I thought this, I felt this, I heard this.....at the end of the day the Lawyers and Jurnos talk in Black and White...Pilot error
Z
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Zeke,
Mutt and I suggest exactly the same thing. In the real world we deal in shades of grey. In the courtroom, with all the time in the world to tear the pilot apart, we are forced to deal in black and white.
Hence our concern with the great number of people in the Industry who choose to ignore the legal reality. A foolish life strategy.
Mutt and I suggest exactly the same thing. In the real world we deal in shades of grey. In the courtroom, with all the time in the world to tear the pilot apart, we are forced to deal in black and white.
Hence our concern with the great number of people in the Industry who choose to ignore the legal reality. A foolish life strategy.
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Zeke,
Around here they use swords, apparently its more hygienic
The 2 sec time delay which you are talking about still exists, it is added after the demonstrated spoiler/brake deployment time, it allows for a full braking configuration without getting deceleration credit for it.
The certification standards are black and white, which is why I mentioned an engine failure 1 second prior to V1, that allows for V1 / Brake application to happen at the same time, followed by throttle chop and spoilers. Now even allowing another 2 seconds as I explained above, there is still a chance that you will go off the runway.
Towers has already talked about tires, add to that rubber deposits, worn brakes, contamination, slope and we end up in the gray world. But how far do you go to account for this gray world, how far do we go to satisfy the legal world?
Anyone care to give us a legal impression on this?
Mutt.
BTW, look out for 777av8r, he has moved from my part of the world to yours.
Around here they use swords, apparently its more hygienic
The 2 sec time delay which you are talking about still exists, it is added after the demonstrated spoiler/brake deployment time, it allows for a full braking configuration without getting deceleration credit for it.
The certification standards are black and white, which is why I mentioned an engine failure 1 second prior to V1, that allows for V1 / Brake application to happen at the same time, followed by throttle chop and spoilers. Now even allowing another 2 seconds as I explained above, there is still a chance that you will go off the runway.
Towers has already talked about tires, add to that rubber deposits, worn brakes, contamination, slope and we end up in the gray world. But how far do you go to account for this gray world, how far do we go to satisfy the legal world?
Anyone care to give us a legal impression on this?
Mutt.
BTW, look out for 777av8r, he has moved from my part of the world to yours.
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Lawyers can and will hang you if something or someone gets broken. One guy here who aborted right at V1 (bird-ingestion) in wet wx and did everything totaly correct, got screwed by the court because he didnt reduce V1 in wet conditions. He hit a threshold marker at 10 knots (no damage to a/c) which caused a bump that caused a pax to hit her head because her seat belt was loosely (not FIRMLY) tightened. He was finaly screwed for "not reducing V1 by 5 knots as recommended by the Operation Manual for wet runway take-offs." The argument (successful in court unfortunately) was that he wouldve been committed to T.O. at that lower V1. At time of severe engine damage he wouldve continued and become airborne, thus avoiding a reject and in so doing avoided contact with the threshold marker.
The defence argued the pilot followed standard RTO procedure meticulousley in a very high stress situation which required an imediate action. The pilot was also mindful of the consequences of entering severe weather in mountainous terrain with only one of the two engines delivering power.
The defence further argued that the use of the word "recommended" does not mean "thou shalt". Unfortunately the judge didnt see it that way. "Its written in your Companys OM in BLACK and WHITE!" was the curt reply.
The fact the silly b!tch of a passenger had her seat belt LOOSELY fastened was thrown out as our Co OM did not specify "FIRMLY FASTENED FOR T.O." just "FASTENED FOR T.O." It does now!
PS He stopped 5ft into the grass past the upwind threshold because of rubber deposits around the 300M touchdown point.
The defence argued the pilot followed standard RTO procedure meticulousley in a very high stress situation which required an imediate action. The pilot was also mindful of the consequences of entering severe weather in mountainous terrain with only one of the two engines delivering power.
The defence further argued that the use of the word "recommended" does not mean "thou shalt". Unfortunately the judge didnt see it that way. "Its written in your Companys OM in BLACK and WHITE!" was the curt reply.
The fact the silly b!tch of a passenger had her seat belt LOOSELY fastened was thrown out as our Co OM did not specify "FIRMLY FASTENED FOR T.O." just "FASTENED FOR T.O." It does now!
PS He stopped 5ft into the grass past the upwind threshold because of rubber deposits around the 300M touchdown point.
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As JT says it very hard to see how you can put these sort of things in Black and White.
If you remember tyhe DC10 overrun accident where people had been operating to manufacturers figures on the DC10 for years only to find that the stopping distance did not take into account ALL brake units worn to just within limits.
The brakes were unable to dissipate the heat and the aircraft went off the end.
RTO limits were adjusted and the brake wear limits were reduced ( by an FAA AD!) on most transport aircraft when they realised it was a major problem.
Yet for years we had gone along with the manufacturers limits - with all the add 1 second here and add 2 seconds there only to find they had got it all wrong !!
If you remember tyhe DC10 overrun accident where people had been operating to manufacturers figures on the DC10 for years only to find that the stopping distance did not take into account ALL brake units worn to just within limits.
The brakes were unable to dissipate the heat and the aircraft went off the end.
RTO limits were adjusted and the brake wear limits were reduced ( by an FAA AD!) on most transport aircraft when they realised it was a major problem.
Yet for years we had gone along with the manufacturers limits - with all the add 1 second here and add 2 seconds there only to find they had got it all wrong !!
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Useful posts from Slasher and GotTheTShirt. This has been my point all along.
The AFM data is quite fine - if the boundary conditions are constrained to approximate those pertaining to the certification tests.
In the majority of cases, overall, accel stop is not limiting and, depending on the extent of pad, we can afford to be a little relaxed. (Fortunately, with little aeroplanes, we usually get to use runways built for big aeroplanes)
In the real world limiting runway case, however, it is quite silly to presume that you will stop in a critical situation - historical data and simulator tests clearly suggest than the typical line pilot is going to be in an awkward situation with a high probability of a runway departure.
Hence the need for considered assessment by the crew on a takeoff by takeoff basis, with due consideration of AFM and OM guidance. I note again that Boeing (quite surprisingly to this observer considering the potential for consequent liability) recommends very strongly in training material that the go/no go decision is, in effect, made before V1.
I have no legal competence. However, the situation for the courtroom is that you had better have a very good and convincing story with answers for each and every argument presented by opposition mouthpieces. While I have survived to date, I have seen a number of very technically competent people made to look like idiots by tactically clever barristers - and this is precisely their job - to win.
The AFM data is quite fine - if the boundary conditions are constrained to approximate those pertaining to the certification tests.
In the majority of cases, overall, accel stop is not limiting and, depending on the extent of pad, we can afford to be a little relaxed. (Fortunately, with little aeroplanes, we usually get to use runways built for big aeroplanes)
In the real world limiting runway case, however, it is quite silly to presume that you will stop in a critical situation - historical data and simulator tests clearly suggest than the typical line pilot is going to be in an awkward situation with a high probability of a runway departure.
Hence the need for considered assessment by the crew on a takeoff by takeoff basis, with due consideration of AFM and OM guidance. I note again that Boeing (quite surprisingly to this observer considering the potential for consequent liability) recommends very strongly in training material that the go/no go decision is, in effect, made before V1.
I have no legal competence. However, the situation for the courtroom is that you had better have a very good and convincing story with answers for each and every argument presented by opposition mouthpieces. While I have survived to date, I have seen a number of very technically competent people made to look like idiots by tactically clever barristers - and this is precisely their job - to win.
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Mutt:
I guess I am lucky that the Jepp runway analysis manuals we use take into account the factors you mention. We have limits for tire speed and brake energy already in the tables, and if contamination is present no flex takeoff procedure. The runway limit data includes the slope. We have data for each runway at each airport, with winds, slope, weight, certification basis, brake energy (in MJ), aircraft and engine models, and runway conditions, aircraft configuration to mention a few, this takes the guess work out of the "gray area".
If you don’t have these available to you it is the airline depriving you of data that already exists to save a dollar.
If you are concerned about runway conditions for stopping, brief for a TOGA takeoff not FLEX/Reduced Temp.
What I don’t see anywhere which I this would be of great benefit to pilot is at V1-what can you takeoff on one engine ? In the sim I have played around with engine failures at V1-10 kts came close to a tale scrape but got the aircraft airborne.
The reason why I think this would be useful is if you were say V1-5 and had an engine failure, contaminated runway (say low friction due ice) I know I can get airborne safely and come back and do and ILS/autoland on one engine with autobrakes even if the vis was 150/0. The hardest part about continuing the takeoff is changing the destination and reprogramming the approach in the FMC.
Getting airborne give you more options (runways/airports/conditions) than the single option if you are rejecting.
GotTheTshirt,
The NTSB did a large study on RTO's and the cause of them, and recommended a number of recommendations were adopted by the FAA and JAA.
The DC10 incident you refer to would not be relevant today as one of the changes in 1988 to the FARs and JARs was to have the RTO performance figures for fully worn brakes for all aircraft (what temp are the brakes assumed to be at the start of the takeoff roll ?). A number of other factors which may make the aircraft or runway less than ideal have been included.
If one were to ask most of the guys the finer points of what is and is not taken into account for RTO they do not have an idea. Most of the guys I see just get the runway analysis book out to takeoff card for the weight and read the figures out, not understanding the factors that were included in the computer analysis derived performance figures.
Z
I guess I am lucky that the Jepp runway analysis manuals we use take into account the factors you mention. We have limits for tire speed and brake energy already in the tables, and if contamination is present no flex takeoff procedure. The runway limit data includes the slope. We have data for each runway at each airport, with winds, slope, weight, certification basis, brake energy (in MJ), aircraft and engine models, and runway conditions, aircraft configuration to mention a few, this takes the guess work out of the "gray area".
If you don’t have these available to you it is the airline depriving you of data that already exists to save a dollar.
If you are concerned about runway conditions for stopping, brief for a TOGA takeoff not FLEX/Reduced Temp.
What I don’t see anywhere which I this would be of great benefit to pilot is at V1-what can you takeoff on one engine ? In the sim I have played around with engine failures at V1-10 kts came close to a tale scrape but got the aircraft airborne.
The reason why I think this would be useful is if you were say V1-5 and had an engine failure, contaminated runway (say low friction due ice) I know I can get airborne safely and come back and do and ILS/autoland on one engine with autobrakes even if the vis was 150/0. The hardest part about continuing the takeoff is changing the destination and reprogramming the approach in the FMC.
Getting airborne give you more options (runways/airports/conditions) than the single option if you are rejecting.
GotTheTshirt,
The NTSB did a large study on RTO's and the cause of them, and recommended a number of recommendations were adopted by the FAA and JAA.
The DC10 incident you refer to would not be relevant today as one of the changes in 1988 to the FARs and JARs was to have the RTO performance figures for fully worn brakes for all aircraft (what temp are the brakes assumed to be at the start of the takeoff roll ?). A number of other factors which may make the aircraft or runway less than ideal have been included.
If one were to ask most of the guys the finer points of what is and is not taken into account for RTO they do not have an idea. Most of the guys I see just get the runway analysis book out to takeoff card for the weight and read the figures out, not understanding the factors that were included in the computer analysis derived performance figures.
Z
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Zeke,
The factors that you are talking about in your Jeppesen analysis are extremely basic, from the phrases that you use, I would guess that you are using a standard Airbus takeoff chart? As for the factors which I mentioned.
Slope: The standard way of calculation slope is to take the runway end elevation and divide the different by the runway length; this gives you a mean elevation that works in most cases. But what about the airports where the slope in your accelerate-go portion is greater than the average? Will you reach 35feet?
Runway surface: For years Bombay’s main runway had severe rubber deposits on it, the airport authority even had the audacity of declaring the runway braking action POOR when wet! This basically put the onus on the airline to decide if they wanted to use the runway or not. How many airlines counted for this in their takeoff calculations?
Contaminated runways: It amazes me that there are airlines taking off from wet/contaminated runways without making any corrections! I still haven’t worked out why this is the one case where Boeing actually produces Ops Manual data for ALL ENGINES.
The FMS in a number of our aircraft has a function for calculating wet V-speeds, but the FAR’s don’t require Boeing to certify this data, therefore they refuse to enable this function! (Its there in CAA aircraft)
This is the sort of gray world that I’m talking about!
That’s enough of my gripes……. The information that you are looking for is available, all that you have to do is fly a Boeing aircraft! I believe that Lufthansa give their crews MIN/MAX V1 speeds, the crew then have the option to pick the V1 that suits the present conditions. The Airbus optimized V-speed methodology is pretty complicated and will depend on the speed ratio that was selected by your airline. But there is nothing stopping your ops people from using a lower speed ratio.
In the black and white legal world, your idea of rotating earlier without any SOP for doing so, will backfire on you.
You have given the impression that most aircraft are now certified using worn brakes. I know that the FAR’s have changed, but the ONLY aircraft which I know was certified using worn brakes (2%) is the MD11. (The rules say nothing about the brake temperature.)
Can anyone tell me of any other aircraft certified with worn brakes, this information should be shown on the accelerate stop distance chart in the AFM.
JT, Boeing will argue that their aircraft are built according to the regulations. While history may have shown that 58% of RTO’s were avoidable, Boeing have passed this information on to airlines in the form of the Takeoff Safety Guide, therefore covering their arses.
Slasher, I would have preferred to see the passenger getting fined for endangering the other passengers lives by not taking adequate care to secure herself into the seat!
Night All.
Mutt.
The factors that you are talking about in your Jeppesen analysis are extremely basic, from the phrases that you use, I would guess that you are using a standard Airbus takeoff chart? As for the factors which I mentioned.
Slope: The standard way of calculation slope is to take the runway end elevation and divide the different by the runway length; this gives you a mean elevation that works in most cases. But what about the airports where the slope in your accelerate-go portion is greater than the average? Will you reach 35feet?
Runway surface: For years Bombay’s main runway had severe rubber deposits on it, the airport authority even had the audacity of declaring the runway braking action POOR when wet! This basically put the onus on the airline to decide if they wanted to use the runway or not. How many airlines counted for this in their takeoff calculations?
Contaminated runways: It amazes me that there are airlines taking off from wet/contaminated runways without making any corrections! I still haven’t worked out why this is the one case where Boeing actually produces Ops Manual data for ALL ENGINES.
The FMS in a number of our aircraft has a function for calculating wet V-speeds, but the FAR’s don’t require Boeing to certify this data, therefore they refuse to enable this function! (Its there in CAA aircraft)
This is the sort of gray world that I’m talking about!
That’s enough of my gripes……. The information that you are looking for is available, all that you have to do is fly a Boeing aircraft! I believe that Lufthansa give their crews MIN/MAX V1 speeds, the crew then have the option to pick the V1 that suits the present conditions. The Airbus optimized V-speed methodology is pretty complicated and will depend on the speed ratio that was selected by your airline. But there is nothing stopping your ops people from using a lower speed ratio.
In the black and white legal world, your idea of rotating earlier without any SOP for doing so, will backfire on you.
You have given the impression that most aircraft are now certified using worn brakes. I know that the FAR’s have changed, but the ONLY aircraft which I know was certified using worn brakes (2%) is the MD11. (The rules say nothing about the brake temperature.)
Can anyone tell me of any other aircraft certified with worn brakes, this information should be shown on the accelerate stop distance chart in the AFM.
JT, Boeing will argue that their aircraft are built according to the regulations. While history may have shown that 58% of RTO’s were avoidable, Boeing have passed this information on to airlines in the form of the Takeoff Safety Guide, therefore covering their arses.
Slasher, I would have preferred to see the passenger getting fined for endangering the other passengers lives by not taking adequate care to secure herself into the seat!
Night All.
Mutt.
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And we keep coming back to the three main concerns -
(a) rule changes generally only apply to new TCs
(b) the real world is only an imperfect approximation to the idealised world specified in the certification processes.
(c) it really is a matter of thinking about the prioritisation of present hazards on a takeoff by takeoff basis .....
(a) rule changes generally only apply to new TCs
(b) the real world is only an imperfect approximation to the idealised world specified in the certification processes.
(c) it really is a matter of thinking about the prioritisation of present hazards on a takeoff by takeoff basis .....
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Zeke,
My point was really that until 1988 RTO performance was as laid down by the manufacturer. Until the accident no one gave it a second thought.
I was at Lockheed when the original RTO performance was tested and I dont know if they went back and did it all with complete sets of worn brakes or just did an analysis.
The allowable brake wear was reduced to allow for all brakes worn less so maybe they just made the brakes comply with the aircraft and not the aircraft comply with the worn brakes ( if you get my meaning !!)
Going back even further A BEA Airspeed Amabassador went off the end due to slush freezing on the landing gear. This hadn't really been considered before and another point which was added to the factors!!
Despite all the testing, factoring, analysis and evaluation it takes an incident to bring it home !
My point was really that until 1988 RTO performance was as laid down by the manufacturer. Until the accident no one gave it a second thought.
I was at Lockheed when the original RTO performance was tested and I dont know if they went back and did it all with complete sets of worn brakes or just did an analysis.
The allowable brake wear was reduced to allow for all brakes worn less so maybe they just made the brakes comply with the aircraft and not the aircraft comply with the worn brakes ( if you get my meaning !!)
Going back even further A BEA Airspeed Amabassador went off the end due to slush freezing on the landing gear. This hadn't really been considered before and another point which was added to the factors!!
Despite all the testing, factoring, analysis and evaluation it takes an incident to bring it home !
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GotTheShirt,
We still operate L1011-500 as corporate machines, they dont have any correction for worn brakes. The certification ruling wasnt retroactive.
The Ambassador certainly woke the CAA up, but for some reason the FAA has totally ignored contaminated runways. Its not as if the information isn’t available, all of the advisory information which is presently available is based on parameters developed in 1960 using a NASA Convair 880!
Mutt
We still operate L1011-500 as corporate machines, they dont have any correction for worn brakes. The certification ruling wasnt retroactive.
The Ambassador certainly woke the CAA up, but for some reason the FAA has totally ignored contaminated runways. Its not as if the information isn’t available, all of the advisory information which is presently available is based on parameters developed in 1960 using a NASA Convair 880!
Mutt
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Mutt,
The charts I have are prepared by Jepp not Airbus, it was one of the things Airbus was snotty about when Boeing bought Jepp, they now have all the performance models for all the current airbus aircraft.
As for slope, it is calculated for each runway direction, eg Rwys 36 & 18 have different slopes at the same airport, one say 36/0.01 and 18/ 0.00.
Aircraft that I know conform to the new FAR 25 standards for takeoff performance are the Airbus A318, A319, A319CJ, A321, A330 and A340; and the Boeing 737-600, 737-700 and 737-800. I don’t know if the BBJ, 777 or 764 are it might cost them too much fuel.
The changes with FAR 25 were not retroactive, but they did change the operational regulations FAR 91, 121, and 135. To my knowledge the FAA has issued an AD for all aircraft above 75000lb/33750kg be capable of absorbing the energy from a maximum-kinetic-energy RTO, even when the brakes are worn to limits that require overhaul.
JAR 25 was retroactive for wet runway performance. The JARs also take into account the distance the aircraft use to line up, the FAR don’t. Every one is snotty about this and not making the rules retroactive, as at the end of the day it gives an economic benefit to FAA registered aircraft, but a safety benefit to others.
The FAA has said the new rules, if implemented, give you an average extra 150 ft for worn brakes, 150 ft for pilot reaction time, and 220 ft for wet runways (they did not specify aircraft type).
One the topic of brakes ….brake wear with carbon brakes and _some_ modern steel brakes (ie read newish a/c Airbus, 744, 777, STC brakes) are designed to give almost consistent braking throughout the life of the item (to the overhaul limit), they can actually be at their worst when brand new. Brake temp is not an issue with carbon brakes, F1 cars run around with red hot carbon brakes, but it is an issue with the thermal plugs.
The new standards also require that wheel brakes with not more than 10 percent of their allowable brake-wear range remaining be used during the certification flight test demonstration of a maximum-kinetic-energy RTO, which is actually not the worst time for carbon brakes.
For wet runways the numbers are crunched for max tire pressure and 2 mm of tread, lower pressure is better in the wet, tires new are at about 12 mm, replaced at about 1.2 mm. The screen height to the go was lowered from 35 down to 15 ft to give pilots to option to go from a lower speed.
The testing for wet runways are done on a fairly slick runway, not the type D or E runways that are at most airports (groves and runways with a rough fiction course added).
I have never operated into Bombay, if its as bad as you describe a half decent lawyer would get up there and put other pilots on the stand to generate a picture that it was common knowledge that it was in poor condition when wet, along with the number of times and spacing of your visits should have lead you and your company to use due caution. They are using similar lines of reasoning for a certain 744 incident taking off on a very lumpy/bumpy wet runway.
GotTheTshirt,
I hear what you are saying, the accident is the test flightwith passengers … the DC-10 you mentioned was a pure design **** up, and in my view criminal. 8 of the 10 brakes failed at only 36% of the original design requirement. Ref National Transportation Safety Board. Special Investigation Report: Brake Performance of the McDonnellDouglas DC-10-30/40 During High Speed, High EnergyRejected Takeoffs, NTSB/SIR-90/01. February 1990., FSF Digest Oct 1988
The charts I have are prepared by Jepp not Airbus, it was one of the things Airbus was snotty about when Boeing bought Jepp, they now have all the performance models for all the current airbus aircraft.
As for slope, it is calculated for each runway direction, eg Rwys 36 & 18 have different slopes at the same airport, one say 36/0.01 and 18/ 0.00.
Aircraft that I know conform to the new FAR 25 standards for takeoff performance are the Airbus A318, A319, A319CJ, A321, A330 and A340; and the Boeing 737-600, 737-700 and 737-800. I don’t know if the BBJ, 777 or 764 are it might cost them too much fuel.
The changes with FAR 25 were not retroactive, but they did change the operational regulations FAR 91, 121, and 135. To my knowledge the FAA has issued an AD for all aircraft above 75000lb/33750kg be capable of absorbing the energy from a maximum-kinetic-energy RTO, even when the brakes are worn to limits that require overhaul.
JAR 25 was retroactive for wet runway performance. The JARs also take into account the distance the aircraft use to line up, the FAR don’t. Every one is snotty about this and not making the rules retroactive, as at the end of the day it gives an economic benefit to FAA registered aircraft, but a safety benefit to others.
The FAA has said the new rules, if implemented, give you an average extra 150 ft for worn brakes, 150 ft for pilot reaction time, and 220 ft for wet runways (they did not specify aircraft type).
One the topic of brakes ….brake wear with carbon brakes and _some_ modern steel brakes (ie read newish a/c Airbus, 744, 777, STC brakes) are designed to give almost consistent braking throughout the life of the item (to the overhaul limit), they can actually be at their worst when brand new. Brake temp is not an issue with carbon brakes, F1 cars run around with red hot carbon brakes, but it is an issue with the thermal plugs.
The new standards also require that wheel brakes with not more than 10 percent of their allowable brake-wear range remaining be used during the certification flight test demonstration of a maximum-kinetic-energy RTO, which is actually not the worst time for carbon brakes.
For wet runways the numbers are crunched for max tire pressure and 2 mm of tread, lower pressure is better in the wet, tires new are at about 12 mm, replaced at about 1.2 mm. The screen height to the go was lowered from 35 down to 15 ft to give pilots to option to go from a lower speed.
The testing for wet runways are done on a fairly slick runway, not the type D or E runways that are at most airports (groves and runways with a rough fiction course added).
I have never operated into Bombay, if its as bad as you describe a half decent lawyer would get up there and put other pilots on the stand to generate a picture that it was common knowledge that it was in poor condition when wet, along with the number of times and spacing of your visits should have lead you and your company to use due caution. They are using similar lines of reasoning for a certain 744 incident taking off on a very lumpy/bumpy wet runway.
GotTheTshirt,
I hear what you are saying, the accident is the test flightwith passengers … the DC-10 you mentioned was a pure design **** up, and in my view criminal. 8 of the 10 brakes failed at only 36% of the original design requirement. Ref National Transportation Safety Board. Special Investigation Report: Brake Performance of the McDonnellDouglas DC-10-30/40 During High Speed, High EnergyRejected Takeoffs, NTSB/SIR-90/01. February 1990., FSF Digest Oct 1988
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Zeke,
A minor point of curiosity ...
Last time I was at Jeppesen in Denver, they were using a very snazzy co-ordinate data base approach from the printed AFM carpets to generate RTOW tables.
Unless Airbus provided them with the AFM software (or permitted customers to do so - and that wouldn't make much sense as the customer would be better off running the thing themselves), then they wouldn't have the worked up performance model.
Or have things changed in more recent times ?
A minor point of curiosity ...
Last time I was at Jeppesen in Denver, they were using a very snazzy co-ordinate data base approach from the printed AFM carpets to generate RTOW tables.
Unless Airbus provided them with the AFM software (or permitted customers to do so - and that wouldn't make much sense as the customer would be better off running the thing themselves), then they wouldn't have the worked up performance model.
Or have things changed in more recent times ?
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Mutt,
If you look at your brake wear indicator pins you will see a flat metal angle bolted onto the brake unit with a metal placard( if its still there!!) on it.
The max brake wear is when you reach the end of the angle bracket.
Originally max wear was right down to the edge of the brake actuator piston housing.
The bolt on angle bit was the AD which effectively reduces the amount of wear you can have.
(!!! what angle bit ??????)
If you look at your brake wear indicator pins you will see a flat metal angle bolted onto the brake unit with a metal placard( if its still there!!) on it.
The max brake wear is when you reach the end of the angle bracket.
Originally max wear was right down to the edge of the brake actuator piston housing.
The bolt on angle bit was the AD which effectively reduces the amount of wear you can have.
(!!! what angle bit ??????)
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JT,
My understaning is that they have the Airbus performance models.
When Boeing bought Jepp, Airbus was pushing very hard to set up an European version of Jepp as they believe Boeing has an unfair commercial advantage. I believe Airbus is still trying to get an agency in Europe set up.
In my view the horse has already bolted.
As far as customers printing their own charts, I think AF, AC, BA, and LH maybe do it themself.
Z
My understaning is that they have the Airbus performance models.
When Boeing bought Jepp, Airbus was pushing very hard to set up an European version of Jepp as they believe Boeing has an unfair commercial advantage. I believe Airbus is still trying to get an agency in Europe set up.
In my view the horse has already bolted.
As far as customers printing their own charts, I think AF, AC, BA, and LH maybe do it themself.
Z