Runway length required for safe operations
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Runway length required for safe operations
I hope you professional pilots will not mind a question from an enthusiast but a recent discussion on another forum raised an interesting question.
Is there any difference in the runway length required for safe operation between a flight operated by an owner pilot, i.e. not a commercial operation, and the same aircraft operated under full commercial operating standards.
Thanks for any replies.
Is there any difference in the runway length required for safe operation between a flight operated by an owner pilot, i.e. not a commercial operation, and the same aircraft operated under full commercial operating standards.
Thanks for any replies.
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Hello!
> Is there any difference in the runway length required for safe operation
Philosophically, there is no difference. It is either safe or it isn't.
Legally, there is indeed a big difference. Private flights are allowed to calculate their runway length requirements using the aeroplane operators manual alone. Commercial operators have to "factor" the figures from the manual, i.e. they need to multiply the values supplied by the manufacturer with a safety factor in order to determine wether or not the operation can legally be done. One such factor that often has to be applied is 1,67. But there are others.
Rumour has it however, that once EU OPS are fully established and will replace JAR OPS, factoring will have to be applied to some non-commercial operations as well.
Greetings, Max
> Is there any difference in the runway length required for safe operation
Philosophically, there is no difference. It is either safe or it isn't.
Legally, there is indeed a big difference. Private flights are allowed to calculate their runway length requirements using the aeroplane operators manual alone. Commercial operators have to "factor" the figures from the manual, i.e. they need to multiply the values supplied by the manufacturer with a safety factor in order to determine wether or not the operation can legally be done. One such factor that often has to be applied is 1,67. But there are others.
Rumour has it however, that once EU OPS are fully established and will replace JAR OPS, factoring will have to be applied to some non-commercial operations as well.
Greetings, Max
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I'd be interested in anyones experience of landing on a runway where you had to remove the factoring, because it was a private flight and otherwise you wouldn't have got in/out. How tight did it feel and how was it for the subsequent departure?
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Now there's a question.
I once worked for a large company who resorted to this on positioning flights using the argument that if you were landing without passengers it wasn't a commercial flight as such, even if you were there to collect punters. Funny how the rest of the world disagreed but hey ho.
Personally I never had to get into the argument as none of those flights came my way but I spoke to few colleagues who had flown them and they described the experience as 'interesting'.
I once worked for a large company who resorted to this on positioning flights using the argument that if you were landing without passengers it wasn't a commercial flight as such, even if you were there to collect punters. Funny how the rest of the world disagreed but hey ho.
Personally I never had to get into the argument as none of those flights came my way but I spoke to few colleagues who had flown them and they described the experience as 'interesting'.
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yes interesting question. My FMS gives me Actual data from the manufacturer and then below that a figure that has the factor of my choice applied to it currently 1.67.
The manufacturers figure does not include the benefit of thrust reversers, although if you were going in somewhere short you would more than likely be very light and have a low Vref anyway In these cases Thrust reversers aren't as effective as from when stopping from higher speeds - but they still help and aren't included in the "raw" figure. Having said all this we are increasingly finding ourselves going into places heavier than usual because we have started tankering fuel.
Airbus succesfully lobbied to have takeoff figures on a wet runway include the benefit of TR's otherwise the A340 would struggle getting in anywhere!
Would I go in somewhere based only on the net figure.....yes..... but not without reverse and not using wet raw figures or with a serious cross wind or gusty conditions.
Having got into your very short runway, you then have the very serious consideration of getting out again with reasonable fuel to get anywhere.
Stopping is not normally a problem for modern bizjets.......accelerating and then stopping normally makes people wince a bit.....
The manufacturers figure does not include the benefit of thrust reversers, although if you were going in somewhere short you would more than likely be very light and have a low Vref anyway In these cases Thrust reversers aren't as effective as from when stopping from higher speeds - but they still help and aren't included in the "raw" figure. Having said all this we are increasingly finding ourselves going into places heavier than usual because we have started tankering fuel.
Airbus succesfully lobbied to have takeoff figures on a wet runway include the benefit of TR's otherwise the A340 would struggle getting in anywhere!
Would I go in somewhere based only on the net figure.....yes..... but not without reverse and not using wet raw figures or with a serious cross wind or gusty conditions.
Having got into your very short runway, you then have the very serious consideration of getting out again with reasonable fuel to get anywhere.
Stopping is not normally a problem for modern bizjets.......accelerating and then stopping normally makes people wince a bit.....
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"I once worked for a large company who resorted to this on positioning flights using the argument that if you were landing without passengers it wasn't a commercial flight as such, even if you were there to collect punters. Funny how the rest of the world disagreed but hey ho"
That company wasn´t german, was it? Indeed the LBA did see it that way the last time I asked.
I switched from comm ops to cooperate and I´m stationed at a fairly short airport (TODA 3597ft, LDA 3323ft) now. The beginning was "different" as the aircraft was new to us as well. But one gets used to it quickly.
@smuff: 1,67 is for jetairplanes. Turboprop and piston aeroplanes (class B as per EU OPS) use 1,43 as rwy factor. Reverse thrust or reversed propellers are not used in this scenario at all (for calculating) and provide another "safety margin".
Most of them do use a factor for takeoff as well, 1,15% of the all engine takeoff distance. (Class A aeroplanes do require a distance for takeoff that is the longest of either accelerate - stop, accelerate - go or all engine takeoff distance) If an aeroplane is not able to produce enough climb with an failed engine after takeoff, then the takeoff weather minima are raised - the idea is, that a pilot then could find a spot to crashland.
As a private operator you would not need to observe any of these, you need just enough runway to achieve takeoff within and vice versa for landing from a 50ft height when crossing the runway threshold. (Att: this is valid for Germany - other countries may have different regs)
We voluntarily use a factor of 1,25 instead of 1,67 for landing and the longest of 3 method for takeoff. (but then our AFM does hold only the LO3 numbers for takeoff anyway)
That company wasn´t german, was it? Indeed the LBA did see it that way the last time I asked.
I switched from comm ops to cooperate and I´m stationed at a fairly short airport (TODA 3597ft, LDA 3323ft) now. The beginning was "different" as the aircraft was new to us as well. But one gets used to it quickly.
@smuff: 1,67 is for jetairplanes. Turboprop and piston aeroplanes (class B as per EU OPS) use 1,43 as rwy factor. Reverse thrust or reversed propellers are not used in this scenario at all (for calculating) and provide another "safety margin".
Most of them do use a factor for takeoff as well, 1,15% of the all engine takeoff distance. (Class A aeroplanes do require a distance for takeoff that is the longest of either accelerate - stop, accelerate - go or all engine takeoff distance) If an aeroplane is not able to produce enough climb with an failed engine after takeoff, then the takeoff weather minima are raised - the idea is, that a pilot then could find a spot to crashland.
As a private operator you would not need to observe any of these, you need just enough runway to achieve takeoff within and vice versa for landing from a 50ft height when crossing the runway threshold. (Att: this is valid for Germany - other countries may have different regs)
We voluntarily use a factor of 1,25 instead of 1,67 for landing and the longest of 3 method for takeoff. (but then our AFM does hold only the LO3 numbers for takeoff anyway)
)
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Gross performace
Under the old ANO AOC all empty flights positioning to/from a public transport sector(s) were "deemed to be Public transport" for all purposes so unfactored distances could not be used and indeed on the CAA Ops inspection it was something they checked for.
Under JAR OPs/EU Ops I am not so sure. Perhaps a JAR OPS manual wizard could lead me to the relevant JAR
Under JAR OPs/EU Ops I am not so sure. Perhaps a JAR OPS manual wizard could lead me to the relevant JAR
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If you want to stay out of trouble use the factored distance at all times. Using the extra distance may just save you one day. It is just not worth the risk reducing safety margins.
All the short landings and records have been set generations ago, so there is no more room for heroes. The 1.67 is for the crew's and pax benefit.
All the short landings and records have been set generations ago, so there is no more room for heroes. The 1.67 is for the crew's and pax benefit.
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I respect your opinion and your safety ethic.
The boss in his aircraft on a private flight wants to go to a 5000ft runway, your 1.67 factored distance is 5300 feet, if you go to the second choice airport he'll get a two hour drive as opposed to 20 minutes.
The raw data is 3175 feet without reverse
What do you do?
The boss in his aircraft on a private flight wants to go to a 5000ft runway, your 1.67 factored distance is 5300 feet, if you go to the second choice airport he'll get a two hour drive as opposed to 20 minutes.
The raw data is 3175 feet without reverse
What do you do?
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Hello!
> What do you do?
When I fly commercially under JAR-OPS I don't go there. Unless we get special permission, which sometimes is possible, even with our strict german authorities. The boss knows the rules, so he won't complain.
When I fly corporate (like we did today) I am happy to go there. As long as the runway is dry (as it was today) and there is no substantial cross- or tailwind. If I don't feel happy about it, I tell the boss. He will understand and we go somewhere different.
Greetings, Max
> What do you do?
When I fly commercially under JAR-OPS I don't go there. Unless we get special permission, which sometimes is possible, even with our strict german authorities. The boss knows the rules, so he won't complain.
When I fly corporate (like we did today) I am happy to go there. As long as the runway is dry (as it was today) and there is no substantial cross- or tailwind. If I don't feel happy about it, I tell the boss. He will understand and we go somewhere different.
Greetings, Max
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Depends where you want to "draw the line". The sensible line is the LFL and BFL, not somewhere in between LFL and landing distance
Some owners can be difficult. If you "help them out" once then some expect it, from then on ("you did it last time Captain so why not again?") and you have backed yourself into a corner. They don't get to be very wealthy by being dictated to in their business dealings.
However they have employed you to operate their aircraft in a safe and responsible manner. Yes they will push the boundaries, mainly to see how far they can get with you. This is where air experience and age comes in.
If something were to go wrong and there was to be an accident, whether it be LFL or BFL related, that same boss (assuming he/she survives) will be the first to enquire "why did you reduce those stated safety margins Captain?"
You will get more respect from these guys if you make a stand and lay the ground rules early. If they don't like it and wont accept it, inform them politely to find someone to operate their multi million $ aircraft, who is willing to operate with less safety margins. If they take you up on your suggestion, then they are probably not worth working for.
BTW, when I am operating an aircraft, as far as I am concerned I am the most important person on that aircraft, as I don't want to risk my life by being pressured into a decision by a novice, who probably knows nothing about aviation safety.
Learnt that many years ago.
Some owners can be difficult. If you "help them out" once then some expect it, from then on ("you did it last time Captain so why not again?") and you have backed yourself into a corner. They don't get to be very wealthy by being dictated to in their business dealings.
However they have employed you to operate their aircraft in a safe and responsible manner. Yes they will push the boundaries, mainly to see how far they can get with you. This is where air experience and age comes in.
If something were to go wrong and there was to be an accident, whether it be LFL or BFL related, that same boss (assuming he/she survives) will be the first to enquire "why did you reduce those stated safety margins Captain?"
You will get more respect from these guys if you make a stand and lay the ground rules early. If they don't like it and wont accept it, inform them politely to find someone to operate their multi million $ aircraft, who is willing to operate with less safety margins. If they take you up on your suggestion, then they are probably not worth working for.
BTW, when I am operating an aircraft, as far as I am concerned I am the most important person on that aircraft, as I don't want to risk my life by being pressured into a decision by a novice, who probably knows nothing about aviation safety.
Learnt that many years ago.
Last edited by weido_salt; 25th Jul 2008 at 22:56.
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Weido
I agree with what you say. The above example is a classic case, there are some guys who will put the extra effort in to get their guy where they need to be and not two hours away.
Some can do this safely and do it, some can no doubt do it and dont wish to do it, some cant do it and do it and become a statistic
Then there are some who can do it but cant be bothered, these are the guys with 5 different types in 5 years who complain about being unlucky with their work.......
In the above case, the aircraft is capable of doing it, its hardly marginal so on the right day in a serviceable aircraft no problem.
It boils down to your sense of self preservation being better than the boss's at all times
I agree with what you say. The above example is a classic case, there are some guys who will put the extra effort in to get their guy where they need to be and not two hours away.
Some can do this safely and do it, some can no doubt do it and dont wish to do it, some cant do it and do it and become a statistic
Then there are some who can do it but cant be bothered, these are the guys with 5 different types in 5 years who complain about being unlucky with their work.......
In the above case, the aircraft is capable of doing it, its hardly marginal so on the right day in a serviceable aircraft no problem.
It boils down to your sense of self preservation being better than the boss's at all times
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".....the aircraft is capable of doing it, its hardly marginal so on the right day in a serviceable aircraft no problem."
How do you know? The right day I assume you mean in relation to wx. If you run off the end after a freak gust up the behind, then it would be the wrong day, would it not?
The aircraft may have been serviceable at t/o but may not be on landing.
How do you know? The right day I assume you mean in relation to wx. If you run off the end after a freak gust up the behind, then it would be the wrong day, would it not?
The aircraft may have been serviceable at t/o but may not be on landing.