Abandoning a S/E Procedure
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Abandoning a S/E Procedure
When can pilots legally/safely abandon a S/E procedure? I realize that pilots cannot accept vectors from a controller – at least initially – when performing a Special S/E procedure. The question is – when can a pilot accept a vector (and altitude assignment) from a controller? At Oakland California we have a S/E Procedure which involves a left turn back to the VOR, located at the field, to enter a specified holding pattern. The Obstacle which is being avoided is the Bay Bridge about 5 miles beyond the runway, so it is well behind the A/C by the time you are 180º and basically pointing downwind for the runway. Could you then accept a vector for an approach to the departure runway – you would be flying over the Bay and there are no obstacle involved.
I understand that the controller doesn’t have the performance information to vector an A/C over future obstacles – while still not clear of them – but I assume that, once an A/C has reached the Minimum Vectoring Altitude for an area, the S/E procedure could be abandoned. Is there any rules or guidelines for this?
Thanks for any info,
LK
I understand that the controller doesn’t have the performance information to vector an A/C over future obstacles – while still not clear of them – but I assume that, once an A/C has reached the Minimum Vectoring Altitude for an area, the S/E procedure could be abandoned. Is there any rules or guidelines for this?
Thanks for any info,
LK
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Two suggestions
(a) put in a suggestion that your performance people liaise with ATC to develop a more compatible procedure
(b) stick with the published procedure until that point where the procedure indicates that it may be varied
(a) put in a suggestion that your performance people liaise with ATC to develop a more compatible procedure
(b) stick with the published procedure until that point where the procedure indicates that it may be varied
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John:
Thanks for the reply. Just to get it straight - these procedures are created by first looking at the performance factors - gradients & obstacles - then they are run by ATC to insure that they don't interfer with traffic conflicts - making sure they don't run through any adjacent traffic patterns, etc. ?
This may sound elementary - but because the Take Off phase of flight only goes to 1500' AGL - would these procedures only pertain until the A/C has reached that altitude.
Thanks for your continuing informative reply's
LK
Thanks for the reply. Just to get it straight - these procedures are created by first looking at the performance factors - gradients & obstacles - then they are run by ATC to insure that they don't interfer with traffic conflicts - making sure they don't run through any adjacent traffic patterns, etc. ?
This may sound elementary - but because the Take Off phase of flight only goes to 1500' AGL - would these procedures only pertain until the A/C has reached that altitude.
Thanks for your continuing informative reply's
LK
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Loke,
Can't speak for other engineers, generally, but
(a) a particular runway may, or may not, have a variety of sensible departures for the OEI case.
(b) the performance (wo)man's task is to find the one with the best weight (payload).
(c) one would normally expect an appropriate level of flight standards input but this certainly doesn't always occur.
(d) if the terminal airspace is busy it makes sense to gain some acceptance from the ATC people but this very often is ignored.
In any case, for most jurisdictions, ATC will accept an emergency call and do their controlling bit to keep other aircraft out of the way .. but it makes life easier if ATC at least knows what a particular operator's type/escape procedure is .. often forgotten by the procedure designer
(e) although many operators only look at the V1 failure case and leave the pilot to his/her own devices for other cases, a prudent procedure designer will cover failure at any point and climb to a level which gives nett clearance above the highest point .. 1500 ft is the nominal certification case but doesn't have much relevance to the real world if the particular runway environs require the aircraft to be driven to whatever higher level is necessary to clear critical obstacles. Again this doesn't happen with some operators.
The sensible pilot (particularly if you have an effective union representation) will make sure that he/she knows the operator's philosophy and approach to the procedure design activity.
Regretably all too often what I might see as being appropriate is not congruent with what some engineers might do ....
Can't speak for other engineers, generally, but
(a) a particular runway may, or may not, have a variety of sensible departures for the OEI case.
(b) the performance (wo)man's task is to find the one with the best weight (payload).
(c) one would normally expect an appropriate level of flight standards input but this certainly doesn't always occur.
(d) if the terminal airspace is busy it makes sense to gain some acceptance from the ATC people but this very often is ignored.
In any case, for most jurisdictions, ATC will accept an emergency call and do their controlling bit to keep other aircraft out of the way .. but it makes life easier if ATC at least knows what a particular operator's type/escape procedure is .. often forgotten by the procedure designer
(e) although many operators only look at the V1 failure case and leave the pilot to his/her own devices for other cases, a prudent procedure designer will cover failure at any point and climb to a level which gives nett clearance above the highest point .. 1500 ft is the nominal certification case but doesn't have much relevance to the real world if the particular runway environs require the aircraft to be driven to whatever higher level is necessary to clear critical obstacles. Again this doesn't happen with some operators.
The sensible pilot (particularly if you have an effective union representation) will make sure that he/she knows the operator's philosophy and approach to the procedure design activity.
Regretably all too often what I might see as being appropriate is not congruent with what some engineers might do ....
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Worth bearing in mind is also that many ATS units (talking Europe here, can't comment on US) are unaware of any particular single-engine procedures, known in my company as "Emergency Turns." Many of these are company-specific as well. Therefore, they may be very surprised to see you turn off the SID, despite a failire. I always include a discussion of what we would say in the very brief call to ATC should we have to fly an Emergency Turn, given the above considerations.
Also, it's worth discriminating between SID tracks which are there for noise only, as well. Certain flat terrain arifields with complex departure turns for noise would find those turns being ignored in the event of a high-weight engine failure, were I in the seat. All with a call of course, albeit brief and to the point.
Squid
Also, it's worth discriminating between SID tracks which are there for noise only, as well. Certain flat terrain arifields with complex departure turns for noise would find those turns being ignored in the event of a high-weight engine failure, were I in the seat. All with a call of course, albeit brief and to the point.
Squid
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I am surprised that pilots would be allowed to disregard a S/E Procedure in Day/VMC. I know of one company which allows a S/E Procedure in Day/VFR conditions only – but there is a specific procedure. I think most pilots would have difficulty estimating there performance S/E when viewing an obstacle in the distance – even if they knew what the restrictive obstacle was – which is usually not indicated in the procedure.
It’s my understanding that in the average twin – you climb is less than 150’ per mile. Many procedures provide an escape route where the critical obstacle may be miles from the field and located opposite the direction of take off. I think I’d stick to the procedure – VFR or not.
John – thank you for you information.
LK
It’s my understanding that in the average twin – you climb is less than 150’ per mile. Many procedures provide an escape route where the critical obstacle may be miles from the field and located opposite the direction of take off. I think I’d stick to the procedure – VFR or not.
John – thank you for you information.
LK
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I think I would concur with Loke's comments .. a pilot in the hot seat is not able to make an assessment of gradient (other than by reference to VSI) and, once you turn away from the scheduled escape procedure .. you are ON YOUR OWN ... with a commercial payload and critical conditions .. the distance to climb the net path to a nominal 1500 ft can be a long way .. especially on a twin jet (due to large speed delta associated with flap retraction and low WAT requirements anyway)
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j_t / LOKE
Whilst in specific circs you are right, as a generalisation I disagree.
2 cases:
1. EDI 24. Emergy turn is R back to the 24 FAF NDB + hold.... Well, you'll firstly be well popular holding at the FAF for the runway in use. Secondly, if you head ~070, you won't hit anything until Norway. I think I can judge the climb gradient needed to avoid sea...
2. BCN 20. Emergy Turn (while you're heading out over the Med) is immediate right turn to an NDB in some hills. Again, thanks, but no thanks, I'll stick to flying over the (flat) blue stuff.
Emergy Turns are a set of procedures that will keep you safe in all weathers, and from a minimum set of choices. However, in good vis, and depending on the exact circs, following them blindly not only strikes me as unnecessary, but potentially poor A'Ship as well....
NoD
(Both the above procedures are of course type/airline specific)
Whilst in specific circs you are right, as a generalisation I disagree.
2 cases:
1. EDI 24. Emergy turn is R back to the 24 FAF NDB + hold.... Well, you'll firstly be well popular holding at the FAF for the runway in use. Secondly, if you head ~070, you won't hit anything until Norway. I think I can judge the climb gradient needed to avoid sea...
2. BCN 20. Emergy Turn (while you're heading out over the Med) is immediate right turn to an NDB in some hills. Again, thanks, but no thanks, I'll stick to flying over the (flat) blue stuff.
Emergy Turns are a set of procedures that will keep you safe in all weathers, and from a minimum set of choices. However, in good vis, and depending on the exact circs, following them blindly not only strikes me as unnecessary, but potentially poor A'Ship as well....
NoD
(Both the above procedures are of course type/airline specific)
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My previous company had a policy that the S/E procedure had to be followed until 3rd segment height at all times. From that point the procedure depended on the visibility.
In IMC the full procedure had to be followed until safety height or if ATC radar was available, the minimum vector altitude.
In VMC, the Captain had the option of tracking as desired as long as terrain clearance was assured. In practice, a visual circuit and landing would be performed.
Typically, if it was a VMC day, the brief would be something like, "track runway heading to 2 dme then turn left heading 260. Once we've reached acceleration altitude, we'll knock it off and return for a visual approach."
In IMC the full procedure had to be followed until safety height or if ATC radar was available, the minimum vector altitude.
In VMC, the Captain had the option of tracking as desired as long as terrain clearance was assured. In practice, a visual circuit and landing would be performed.
Typically, if it was a VMC day, the brief would be something like, "track runway heading to 2 dme then turn left heading 260. Once we've reached acceleration altitude, we'll knock it off and return for a visual approach."
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NigelOnDraft:
Actually that was precisely my original point – that there seemed to be S/E Procedures which didn’t seem very realistic – especially at the end - though I’m sure they accomplished the job of avoiding terrain during S/E operations. On the other hand a simple statement that it’s an emergency and the pilot can do what they want, could lead to unintended consequences, especially when more complex S/E Procedures are involved.
I like FlareArmed’s common sense guidance which are procedure at his previous airline. Also john_tullamarine’s always wise counsel to ensure that reasonable S/E procedures are produced to avoid some of the issues that are brought up by NigelOnDraft.
I stick to my statements that it’s difficult for a pilot to evaluate whether a plane will clear an obstacle when they are in S/E operations – even in VFR day. This doesn’t even take into account the obstacle that he is not looking at, which may be miles away – and is really the critical obstacle.
LK
Actually that was precisely my original point – that there seemed to be S/E Procedures which didn’t seem very realistic – especially at the end - though I’m sure they accomplished the job of avoiding terrain during S/E operations. On the other hand a simple statement that it’s an emergency and the pilot can do what they want, could lead to unintended consequences, especially when more complex S/E Procedures are involved.
I like FlareArmed’s common sense guidance which are procedure at his previous airline. Also john_tullamarine’s always wise counsel to ensure that reasonable S/E procedures are produced to avoid some of the issues that are brought up by NigelOnDraft.
I stick to my statements that it’s difficult for a pilot to evaluate whether a plane will clear an obstacle when they are in S/E operations – even in VFR day. This doesn’t even take into account the obstacle that he is not looking at, which may be miles away – and is really the critical obstacle.
LK
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As Nigel has stated, some escape routes are totally absurd and ridicolous.
If I'm taking off toward the sea, like in the LEBL 20 example, I certainly won't head back toward the mountains or incoming traffic.
"Runway heading 3000ft, hold wherever we like over the sea".
End of the briefing.
These escape routes are often defined by wannabees pilots who'd better stay in a university classroom instead of a cockpit.
If I'm taking off toward the sea, like in the LEBL 20 example, I certainly won't head back toward the mountains or incoming traffic.
"Runway heading 3000ft, hold wherever we like over the sea".
End of the briefing.
These escape routes are often defined by wannabees pilots who'd better stay in a university classroom instead of a cockpit.
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Well this clearly involves some airmanship and opinions may vary somewhat, and this is simply one of many:
On DEP: the emergency turns in rwy analysis are usually for obstacle avoidance and they must be briefed with every departure and followed in IMC. Turns mandated by noise abatement and other 'cosmatic' factors are void and null with emergency declaration. The general practice is to first fly the airplane, do recall items, clean up, reduce thrust to MCT, trim, then call ATC let alone accepting turns. If contacted by ATC in the meantime, decalre emergency and say you'll call back.
Normally they don't give vectors before positive control and 1000' AGL. But if there is emergency turn, you have to include it in your procedure, all the more reason to spend the shortest time on the radio. Once all established, normally ATC helps out by giving vectors for a landing or to your TO alternate as the case may be. If possible, it is probably better to take longer legs on vectors, DME hold, turns on the good engine,... as to opposed to normal tight hold.
On GA however, it is different and one HAS to follow the procedure to avoid obstacles or worse yet collision, unless of course you have time to ask for rwy heading 3000', which is always the best for ENG out TO and GAs.
As for the original question, A ONE ENG INOP procedure ends when the airplane is safely on the ground and PAX/CREW are either evacuated or deplaned!
On DEP: the emergency turns in rwy analysis are usually for obstacle avoidance and they must be briefed with every departure and followed in IMC. Turns mandated by noise abatement and other 'cosmatic' factors are void and null with emergency declaration. The general practice is to first fly the airplane, do recall items, clean up, reduce thrust to MCT, trim, then call ATC let alone accepting turns. If contacted by ATC in the meantime, decalre emergency and say you'll call back.
Normally they don't give vectors before positive control and 1000' AGL. But if there is emergency turn, you have to include it in your procedure, all the more reason to spend the shortest time on the radio. Once all established, normally ATC helps out by giving vectors for a landing or to your TO alternate as the case may be. If possible, it is probably better to take longer legs on vectors, DME hold, turns on the good engine,... as to opposed to normal tight hold.
On GA however, it is different and one HAS to follow the procedure to avoid obstacles or worse yet collision, unless of course you have time to ask for rwy heading 3000', which is always the best for ENG out TO and GAs.
As for the original question, A ONE ENG INOP procedure ends when the airplane is safely on the ground and PAX/CREW are either evacuated or deplaned!
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This is a very interesting & complex subject. In my experience, these emergency turns are usually company specific, and mostly need to be followed at any time there is an engine failure. Day night VMC IMC irrelevant unless specified. The real problem is that ATC are not aware of the particular procedure for each airline and aircraft type.
When the crew is busy aviating and navigating, there might not be too much capacity to inform ATC of needed deviation from clearance. What if the frequency is in use just when you have the chance to make the call? Then what if there is conflicting traffic and you are told to maintain a heading or continue as cleared? Or "are you declaring an emergency?" "how many POB?" "what is your endurance?" "confirm you require to turn left onto heading xxx?" All this just as you're performing near max capacity to get everything else, including communication, done correctly.
I cannot believe we should need to inform ATC of our intentions in the event of an engine failure at every airfield where there is such a procedure. Try this at some foreign airfields and you'll have take-off clearance cancelled or delayed. Probably won't make that slot time. Too many times and you won't have a job.
We cannot ignore the fact that ATC should know in advance of the possibilities. The main point really raised by this post should be how we ensure they do know each single engine procedure for all companies and each of their aircraft types The difficulties don't stop there. If your particular procedure is day night VMC IMC specific, does everyone know which procedure? What if ATC think its night VMC and crew decide its still daylight, but IMC?
A situation I have faced is very out of date emergency turn procedure to a non existant navaid. Even if I do this, its harder to communicate my intention.
At another airfield, very soon after take-off an emergency turn was required over a close spaced parallel runway with exactly simultaneous military traffic on another frequency. The North Asian military controller had a very slippery grip of English, the military thought they were King and the local F/O doesn't want to make waves, no matter how well briefed. How is a controller going to make some traffic space when these guys have actually previously done a barrel roll around my A321 at 500ft just as I became visual on ILS final? If the aircraft is heavy, hot day and tailwind we will hit a hill by not turning. Just hope the military jet will break left to avoid a collision.
My life was greatly simplified by refusing to operate to that particular airfield and then retirement from aviation.
Those of you that have a long way yet to go, and who really care about such matters, have my sympathy. Try to solve this problem somehow.
When the crew is busy aviating and navigating, there might not be too much capacity to inform ATC of needed deviation from clearance. What if the frequency is in use just when you have the chance to make the call? Then what if there is conflicting traffic and you are told to maintain a heading or continue as cleared? Or "are you declaring an emergency?" "how many POB?" "what is your endurance?" "confirm you require to turn left onto heading xxx?" All this just as you're performing near max capacity to get everything else, including communication, done correctly.
I cannot believe we should need to inform ATC of our intentions in the event of an engine failure at every airfield where there is such a procedure. Try this at some foreign airfields and you'll have take-off clearance cancelled or delayed. Probably won't make that slot time. Too many times and you won't have a job.
We cannot ignore the fact that ATC should know in advance of the possibilities. The main point really raised by this post should be how we ensure they do know each single engine procedure for all companies and each of their aircraft types The difficulties don't stop there. If your particular procedure is day night VMC IMC specific, does everyone know which procedure? What if ATC think its night VMC and crew decide its still daylight, but IMC?
A situation I have faced is very out of date emergency turn procedure to a non existant navaid. Even if I do this, its harder to communicate my intention.
At another airfield, very soon after take-off an emergency turn was required over a close spaced parallel runway with exactly simultaneous military traffic on another frequency. The North Asian military controller had a very slippery grip of English, the military thought they were King and the local F/O doesn't want to make waves, no matter how well briefed. How is a controller going to make some traffic space when these guys have actually previously done a barrel roll around my A321 at 500ft just as I became visual on ILS final? If the aircraft is heavy, hot day and tailwind we will hit a hill by not turning. Just hope the military jet will break left to avoid a collision.
My life was greatly simplified by refusing to operate to that particular airfield and then retirement from aviation.
Those of you that have a long way yet to go, and who really care about such matters, have my sympathy. Try to solve this problem somehow.
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LEM:
Here Here! By the looks of some of these "procedures" they have no doubt ignored all ATC/Traffic considerations. They use the single (simple?) minded goal to get the company more liftoff weight. End of story.
Fly Safer
These escape routes are often defined by wannabees pilots who'd better stay in a university classroom instead of a cockpit.
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Sorry! Back to the original question.
The approved procedure is discontinued when it has been fully completed. If crew decide on safety grounds to discontinue the procedure, that does not seem too unreasonable to me. If the procedure is discontinued for other reasons, the crew may have some difficulty later defending such a decision.
If the procedure specified after a certain point that the remainer was for separation or airspace requirements, I believe following a reasonable ATC instruction would then be acceptable but not otherwise. What is "reasonable"? Depend on circumstances. If you are very familiar with the area and procedures, you are using first language of yourself and controller and radar environment with transponder altitude capability, reasonable is easier to define. Take away some of these more agreeable circumstances and deviation is more difficult to justify. Unfortunately complience is also more difficult.
The approved procedure is discontinued when it has been fully completed. If crew decide on safety grounds to discontinue the procedure, that does not seem too unreasonable to me. If the procedure is discontinued for other reasons, the crew may have some difficulty later defending such a decision.
If the procedure specified after a certain point that the remainer was for separation or airspace requirements, I believe following a reasonable ATC instruction would then be acceptable but not otherwise. What is "reasonable"? Depend on circumstances. If you are very familiar with the area and procedures, you are using first language of yourself and controller and radar environment with transponder altitude capability, reasonable is easier to define. Take away some of these more agreeable circumstances and deviation is more difficult to justify. Unfortunately complience is also more difficult.
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This is an interesting topic – hate to see it die without generating more inputs.
Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?
Do any Operators provide a S/E Procedure with optional procedures within that procedure – that is either go to X Intersection and hold, or if above an altitude (or some other criteria) accept vectors?
I think most here have implied that they would not accept vectors from ATC if there was any doubt as to whether it was based on anticipated performance of the A/C, by ATC – that is in the direction of obstacles not yet cleared. On the other hand – many have pointed out the absurdity of going to a holding pattern when you should be heading downwind for a landing – or worse yet driving into a bee’s nest of traffic when a safer course is evident.
The issue of whether ATC does know – or should know about these procedures - is another interesting question.
LK
Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?
Do any Operators provide a S/E Procedure with optional procedures within that procedure – that is either go to X Intersection and hold, or if above an altitude (or some other criteria) accept vectors?
I think most here have implied that they would not accept vectors from ATC if there was any doubt as to whether it was based on anticipated performance of the A/C, by ATC – that is in the direction of obstacles not yet cleared. On the other hand – many have pointed out the absurdity of going to a holding pattern when you should be heading downwind for a landing – or worse yet driving into a bee’s nest of traffic when a safer course is evident.
The issue of whether ATC does know – or should know about these procedures - is another interesting question.
LK
Interesting topic.
the day VMC question is always a hot topic, and in my opinion visually avoiding terrain simply means that you see the hill as you run into it!
35 (or 50) ft isn't much, adding gross to net margins doesn't add much really, and in most cases if you depart RTOW (obstacle) limited and have a failure you will get GPWS etc blaring in your ear.
Saying that you can determine visually that you can miss that hill over there is unrealistic in many cases, and simply gives the pilots a false sense of security.
Another interesting topic is airmanship.
many are quick to accuse others of lacking airmanship, but to date I have yet to see the definitive manual on airmanship.
What is one persons definition is different to another.
Food for thought!
the day VMC question is always a hot topic, and in my opinion visually avoiding terrain simply means that you see the hill as you run into it!
35 (or 50) ft isn't much, adding gross to net margins doesn't add much really, and in most cases if you depart RTOW (obstacle) limited and have a failure you will get GPWS etc blaring in your ear.
Saying that you can determine visually that you can miss that hill over there is unrealistic in many cases, and simply gives the pilots a false sense of security.
Another interesting topic is airmanship.
many are quick to accuse others of lacking airmanship, but to date I have yet to see the definitive manual on airmanship.
What is one persons definition is different to another.
Food for thought!
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Loke
Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?
At airports which require extra zoom, we have different takeoff charts for normal t/o at light weights and asterik charts whciha require a special S/E procedure - difference of maybe 3 tonnes paylaod, and different clean up heights.
Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?
At airports which require extra zoom, we have different takeoff charts for normal t/o at light weights and asterik charts whciha require a special S/E procedure - difference of maybe 3 tonnes paylaod, and different clean up heights.
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Couple of points.
(a) the net to gross margin doesn't give you much fat to play with near the departure end of the runway (depends on which case is limiting and how limiting the runway is) but provides a significant margin by the time you get to the fourth segment particularly.
(b) no reason why you can't have several procedures for one runway based on whatever criteria a particular operator considers important or appropriate .. only depends on how much work the operator wants to pay for.
(a) the net to gross margin doesn't give you much fat to play with near the departure end of the runway (depends on which case is limiting and how limiting the runway is) but provides a significant margin by the time you get to the fourth segment particularly.
(b) no reason why you can't have several procedures for one runway based on whatever criteria a particular operator considers important or appropriate .. only depends on how much work the operator wants to pay for.
Last edited by john_tullamarine; 27th Sep 2003 at 08:36.