Question regarding Actual and available Landing distance...
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#GC
That quote is part of a section which addresses the special case where the destination at dispatch does not meet the factored landing distance criteria, but the alternate does. It is not a general provision which applies to all cases.
The FULL text of 1.515(d) is
It's a very special condition and not a general requirement.
That quote is part of a section which addresses the special case where the destination at dispatch does not meet the factored landing distance criteria, but the alternate does. It is not a general provision which applies to all cases.
The FULL text of 1.515(d) is
If an operator is unable to comply with subparagraph (c)(1) above for a destination aerodrome having a single runway where a landing depends
upon a specified wind component, an aeroplane may be despatched if 2 alternate aerodromes are designated which permit full compliance with subparagraphs (a), (b) and (c). Before commencing an approach to land at the destination aerodrome the commander must satisfy himself that a landing can be made in full compliance with JAR–OPS 1.510 and sub-paragraphs (a) and (b) above.
upon a specified wind component, an aeroplane may be despatched if 2 alternate aerodromes are designated which permit full compliance with subparagraphs (a), (b) and (c). Before commencing an approach to land at the destination aerodrome the commander must satisfy himself that a landing can be made in full compliance with JAR–OPS 1.510 and sub-paragraphs (a) and (b) above.
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MFS, good to see you jumping in here 
Presuming that the original poster "is" flying a Global Express, can you please tell us what certification criteria was used with this aircraft? My personal opinion is that it should be treated like an airliner whilst in operation.
Rgds
Mutt
Presuming that the original poster "is" flying a Global Express, can you please tell us what certification criteria was used with this aircraft? My personal opinion is that it should be treated like an airliner whilst in operation.
Rgds
Mutt
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If I can put a simpleton's thoughts to the question ...
(a) the factors are the result of a lot of history and appear to be able to stand the test of real world operations
(b) let's suppose we put the rules to one side for the moment ?
(c) here we are, out for a nice day's flying, and, for whatever reason, need to land ...
(i) if I have a runway with the normal factors available, then I will be relaxed in all likelihood
(ii) if I don't then I will be looking to prioritise the available runways according to various criteria including length
(iii) if I only have around the OEM's actual figures, then I will be very concerned and expect to go off the far end at a lowish speed (and I have been in the aircraft during performance landing trials and the exercise frightened me witless)
Now,
(a) if my worsening predicament was caused by one or more abnormals or emergencies, then I would be declaring the situation, go for the overall best risk situation and be quite prepared to argue my case in court after the prang
(b) if my prang had something to do with my being a bit cavalier and taking a "short" runway just because I thought it would be a good idea .. then I'd not be all that enthusiastic about my chances in court afterwards.
(a) the factors are the result of a lot of history and appear to be able to stand the test of real world operations
(b) let's suppose we put the rules to one side for the moment ?
(c) here we are, out for a nice day's flying, and, for whatever reason, need to land ...
(i) if I have a runway with the normal factors available, then I will be relaxed in all likelihood
(ii) if I don't then I will be looking to prioritise the available runways according to various criteria including length
(iii) if I only have around the OEM's actual figures, then I will be very concerned and expect to go off the far end at a lowish speed (and I have been in the aircraft during performance landing trials and the exercise frightened me witless)
Now,
(a) if my worsening predicament was caused by one or more abnormals or emergencies, then I would be declaring the situation, go for the overall best risk situation and be quite prepared to argue my case in court after the prang
(b) if my prang had something to do with my being a bit cavalier and taking a "short" runway just because I thought it would be a good idea .. then I'd not be all that enthusiastic about my chances in court afterwards.
Mutt states
FAR 121.195 states....no person operating a turbine engine powered airplane may take off that airplane unless its weight on arrival, allowing for normal consumption of fuel and oil in flight (in accordance with the landing distance set forth in the Airplane Flight Manual for the elevation of the destination airport and the wind conditions anticipated there at the time of landing), would allow a full stop landing at the intended destination airport within 60 percent of the effective length
So getting back to the original question, once you are inflight you can forget about the 60% rule whilst applying corrections.
Mutt you have it soooo wrong.
The rule is, unambiguously, if you have the problem at dispatch, you must not go unless all factors are taken into account for your landing. You MUST factor by 1.67 and then the brake degradation factor.
If you dispatch a serviceable aircraft and get the problem after airborne, then and only then the factors do not apply.
You are using semantics by highlighting the take off bit. If you take off and say once airborne I don't need the factors, then you have in fact done an illegal takeoff. Why? - because you conducted the take off whilst planning to land at a destination where your landing weight was such that you could not meet the factord landing distance. So you breached the takeoff rule before you got anywhere near your landing.
This is the rule and that's that. Don't mean to sound arrogantly forceful, but if you took Mutt's view, why on earth would any rule about this have been written in the first place???
FAR 121.195 states....no person operating a turbine engine powered airplane may take off that airplane unless its weight on arrival, allowing for normal consumption of fuel and oil in flight (in accordance with the landing distance set forth in the Airplane Flight Manual for the elevation of the destination airport and the wind conditions anticipated there at the time of landing), would allow a full stop landing at the intended destination airport within 60 percent of the effective length
So getting back to the original question, once you are inflight you can forget about the 60% rule whilst applying corrections.
Mutt you have it soooo wrong.
The rule is, unambiguously, if you have the problem at dispatch, you must not go unless all factors are taken into account for your landing. You MUST factor by 1.67 and then the brake degradation factor.
If you dispatch a serviceable aircraft and get the problem after airborne, then and only then the factors do not apply.
You are using semantics by highlighting the take off bit. If you take off and say once airborne I don't need the factors, then you have in fact done an illegal takeoff. Why? - because you conducted the take off whilst planning to land at a destination where your landing weight was such that you could not meet the factord landing distance. So you breached the takeoff rule before you got anywhere near your landing.
This is the rule and that's that. Don't mean to sound arrogantly forceful, but if you took Mutt's view, why on earth would any rule about this have been written in the first place???
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Rodney rude, I never said to IGNORE the problem until airborne and to do so is totally illegal. To me the rule is clear, if you have the problem on the ground you account for it during takeoff and landing by applying the applicable penalties and apply the applicable factoring. If you have the problem inflight you account for it during landing with the applicable penalties, no factoring required by "regulation".
Mutt
Mutt
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Agree 100% with mutt, except to add also that if you have a system failure which would require you to consult either the abnormal or emergencies sections of the flight manual, then even if there are no additional distance factors in the AFM you should not be dispatching unless the MEL provides coverage to do so.
if it does provide such coverage, then the MEL should also provide the instructions for dispatch, including any additional performance factors which should be applied. If for some bizarre reason it provides no factors, or factors which differ from the abnormal procedures, my take would be that the MEL is the legal authority to dispatch in the configuration, and applies. (Though if the difference is significant I'd be asking myself, and the OEM, why)
To answer mutt's question, the GEX was certified as a Part 25 aircraft, to the same sets of rules as other large transport category aircraft. It also meets the majority of the operationally derived design requirements for a Part 121 or equivalent operator (here I'm thinking things like FDR rules) but there are some exceptions. Right now there are no GEXs in actual airline operations (that I know of), and so I don't believe there is a reinforced cockpit door available (to give an example). There's also no explicit ETOPS operations, although obviously the aircraft has the performance range-wise to be well into ETOPS territory. I'm not sure if any of the Part 91 (or equivalent) operators use ETOPS-equivalent planning for their long overwater routings.
if it does provide such coverage, then the MEL should also provide the instructions for dispatch, including any additional performance factors which should be applied. If for some bizarre reason it provides no factors, or factors which differ from the abnormal procedures, my take would be that the MEL is the legal authority to dispatch in the configuration, and applies. (Though if the difference is significant I'd be asking myself, and the OEM, why)
To answer mutt's question, the GEX was certified as a Part 25 aircraft, to the same sets of rules as other large transport category aircraft. It also meets the majority of the operationally derived design requirements for a Part 121 or equivalent operator (here I'm thinking things like FDR rules) but there are some exceptions. Right now there are no GEXs in actual airline operations (that I know of), and so I don't believe there is a reinforced cockpit door available (to give an example). There's also no explicit ETOPS operations, although obviously the aircraft has the performance range-wise to be well into ETOPS territory. I'm not sure if any of the Part 91 (or equivalent) operators use ETOPS-equivalent planning for their long overwater routings.
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ETOPS below 100000 Lbs ? EROPS yes... The Glex was the first to be able to face the 180 min OEI rule; the Glf are approvable as well. I am not aware of similar rules for FAA land..
AFAIK, private operators just fly.....everything else is just a plane... LoL
AFAIK, private operators just fly.....everything else is just a plane... LoL
Mutt are we saying the same thing a different way? Noted, no you didn't say just ignore it.
1. Problem exists on the ground with brakes. 2 factors required, 1.67, and the braking factor. If actual landing distance (normal, no failure ops) x 1.67 x brake problem factor is longer than the landing distance available -- no go.
2. If problem occurs airborne, 1.67 factor disappears. All you need is actual landing distance normal ops x braking factor.
If number 1 above is the case, and the lda is not long enough, maybe you could flight plan somwehere else that meets the lda requirements and then do an inflight divert to where you really want to go - but is that flirting with the rules to make it work in your favour?? I'll leave that one up to you as to whether that is good airmanship or not. But realistically, in the corporate world, if you can get the boss there, then do it.
I hope that clears up my first post interpretation. Have a great day.
Rod
1. Problem exists on the ground with brakes. 2 factors required, 1.67, and the braking factor. If actual landing distance (normal, no failure ops) x 1.67 x brake problem factor is longer than the landing distance available -- no go.
2. If problem occurs airborne, 1.67 factor disappears. All you need is actual landing distance normal ops x braking factor.
If number 1 above is the case, and the lda is not long enough, maybe you could flight plan somwehere else that meets the lda requirements and then do an inflight divert to where you really want to go - but is that flirting with the rules to make it work in your favour?? I'll leave that one up to you as to whether that is good airmanship or not. But realistically, in the corporate world, if you can get the boss there, then do it.
I hope that clears up my first post interpretation. Have a great day.
Rod
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rodney,
You legally cannot do that, you are inflight replanning. That means all the factoring has to happen at point again...
The real question (in my mind) is: how happy is the boss if something goes wrong and you slide of the end? Most bosses (all the bosses I have worked for at least) accept no, they have hired you to take them safely from a to b.
And if b is not possible think of an alternate destination, I've never had a problem that way.
GC
You legally cannot do that, you are inflight replanning. That means all the factoring has to happen at point again...
The real question (in my mind) is: how happy is the boss if something goes wrong and you slide of the end? Most bosses (all the bosses I have worked for at least) accept no, they have hired you to take them safely from a to b.
And if b is not possible think of an alternate destination, I've never had a problem that way.
GC
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maybe you could flight plan somwehere else that meets the lda requirements and then do an inflight divert to where you really want to go
Mutt.
No Mutt, not for real. Let me clarify.
If tone of voice could come with the written word then what I said would be clearer. I re read my post and it is clear to me that when I mentioned the inflight replanning idea AND THEN said "but is that flirting with the rules to make them work in your favour. I'll leave that up to you to determine if that is good airmanship or not." Usually if someone says that then the answer they have themselves is "No its not" And that is my stand on it. No its not. But granted my last statement does tend allude to me feeling it is okay to flirt with the rules. I didn't mean that. But its hard to argue against that is how it looks.
I am surprised at your response - I thought my earlier posts in response to you was EXACTLY that you cannot ignore the rules before departure and just say its okay, the rules change airborne. My stance has not changed. You cannot ignore the factors prior to departure. If you do you are flirting with the rules and it is not good airmanship. I was never suggesting that that is what I'd do.
If tone of voice could come with the written word then what I said would be clearer. I re read my post and it is clear to me that when I mentioned the inflight replanning idea AND THEN said "but is that flirting with the rules to make them work in your favour. I'll leave that up to you to determine if that is good airmanship or not." Usually if someone says that then the answer they have themselves is "No its not" And that is my stand on it. No its not. But granted my last statement does tend allude to me feeling it is okay to flirt with the rules. I didn't mean that. But its hard to argue against that is how it looks.
I am surprised at your response - I thought my earlier posts in response to you was EXACTLY that you cannot ignore the rules before departure and just say its okay, the rules change airborne. My stance has not changed. You cannot ignore the factors prior to departure. If you do you are flirting with the rules and it is not good airmanship. I was never suggesting that that is what I'd do.
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Hi Chaps,
I've been reading all this with some amusement as some seem to get wordpicky...
EU-OPS want you to have your landing distance factored by 60 % before you takeoff. (Commercial transport!)
This is also done, to include possible system failures and still be able to go there safely.
The factored ALD (actual landing distance) is called LFL (landing field length) in Bombardier books. This must be met at your destination before you takeoff.
The QRH that is mentioned in the very first post applies only in flight (so after takeoff) therefor the already factored distance ALD x 1,67=LFL is still good to land as the failed system asks for ALD x 1,55 only.
The tables provided have to be used when you handle the (at takeoff) unforeseen system malfunction.
Regardless of private or commercial, EU-OPS or other regulations, the GLEX QRH Volume 1 has a section called GO/NOGO in the back. (That's where you look if suddenly a MSG comes up before you leave) - and it says with BRAKES DEGRADED - NOGO.
So not even worth the discussion if you have to factor twice your landing distance, because you simply should not take off with that MSG.
A document that we would surely have to consult before takeoff with a component failed is the MEL.
There, I do not know any system that would require a longer (factored) runway on landing.
have a nice evening
MJ
I've been reading all this with some amusement as some seem to get wordpicky...
EU-OPS want you to have your landing distance factored by 60 % before you takeoff. (Commercial transport!)
This is also done, to include possible system failures and still be able to go there safely.
The factored ALD (actual landing distance) is called LFL (landing field length) in Bombardier books. This must be met at your destination before you takeoff.
The QRH that is mentioned in the very first post applies only in flight (so after takeoff) therefor the already factored distance ALD x 1,67=LFL is still good to land as the failed system asks for ALD x 1,55 only.
The tables provided have to be used when you handle the (at takeoff) unforeseen system malfunction.
Regardless of private or commercial, EU-OPS or other regulations, the GLEX QRH Volume 1 has a section called GO/NOGO in the back. (That's where you look if suddenly a MSG comes up before you leave) - and it says with BRAKES DEGRADED - NOGO.
So not even worth the discussion if you have to factor twice your landing distance, because you simply should not take off with that MSG.
A document that we would surely have to consult before takeoff with a component failed is the MEL.
There, I do not know any system that would require a longer (factored) runway on landing.
have a nice evening
MJ
Last edited by macjet; 27th May 2010 at 19:37.
