Engine Failure After CDP
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Engine Failure After CDP
Gentlemen,
What answers do you have to the following conundrum? In particular I would like to hear what Nick Lappos, Peter Manktellow and Nigel Osborne have in the way of comments. I refer to the S76 since that is what I fly.
There seems to be a deal of confusion as to how an engine failure is to be handled when the failure happens after CDP (operating to Category A) when taking off from a runway where the length of the runway is the limiting factor for the continued take off case (that is there is no clearway over which the acceleration to Vtoss can be made). Obviously in this situation the runway available is in excess of that required to handle the reject situation should the failure occur prior to CDP. Some are of the opinion that a reject may still be made when the failure occurs above CDP “if I THINK there is sufficient runway available to do so”. Others are of the mind that because the success of the reject is unknown when attempting the manoeuvre when above CDP (ie not ‘assured’ as required by the regs) the take off must be continued even though you may be certain in your own mind that the reject can safely be accomplished – the extreme case often cited is how do you handle the situation when departing from a 10,000 foot runway. Even departing from a 10,000 footer you reach a point where the success of an abort/landing is no longer ‘assured’.
Blue Skies, Brian
What answers do you have to the following conundrum? In particular I would like to hear what Nick Lappos, Peter Manktellow and Nigel Osborne have in the way of comments. I refer to the S76 since that is what I fly.
There seems to be a deal of confusion as to how an engine failure is to be handled when the failure happens after CDP (operating to Category A) when taking off from a runway where the length of the runway is the limiting factor for the continued take off case (that is there is no clearway over which the acceleration to Vtoss can be made). Obviously in this situation the runway available is in excess of that required to handle the reject situation should the failure occur prior to CDP. Some are of the opinion that a reject may still be made when the failure occurs above CDP “if I THINK there is sufficient runway available to do so”. Others are of the mind that because the success of the reject is unknown when attempting the manoeuvre when above CDP (ie not ‘assured’ as required by the regs) the take off must be continued even though you may be certain in your own mind that the reject can safely be accomplished – the extreme case often cited is how do you handle the situation when departing from a 10,000 foot runway. Even departing from a 10,000 footer you reach a point where the success of an abort/landing is no longer ‘assured’.
Blue Skies, Brian
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Brian....
BK will kill you for posting this question...unless you are BK???
Cat A...Gee where do we start?
Cat A assures you that you can either:
1...Reject onto the surface you took off from after an OEI before CDP
or
2...Gain Vtoss then Vy and fly away OEI after CDP.
When do you use CAT A....?
Only when the ground ahead of you can't be used for an OEI landing....!!
There are a number of CAT A variations, Runway, Heliport and Elevated Pad, with the Heliport being the most restrictive.
To fly CAT A you must give something away to ensure the CAT A profiles after CDP and OEI are achieved....and that cost is Payload. The MTOW must be reduced on your aircraft if you wish to fly CAT A.
The dumb question I must ask, is that if you have heaps of runway in front of you [as you would at an RAAF Base] then why would you want to use CAT A...?
Use CAT B and nominate Vtoss, Vy and the Committed Call when you physically can't land on the runway ahead.
Cat A...Gee where do we start?
Cat A assures you that you can either:
1...Reject onto the surface you took off from after an OEI before CDP
or
2...Gain Vtoss then Vy and fly away OEI after CDP.
When do you use CAT A....?
Only when the ground ahead of you can't be used for an OEI landing....!!
There are a number of CAT A variations, Runway, Heliport and Elevated Pad, with the Heliport being the most restrictive.
To fly CAT A you must give something away to ensure the CAT A profiles after CDP and OEI are achieved....and that cost is Payload. The MTOW must be reduced on your aircraft if you wish to fly CAT A.
The dumb question I must ask, is that if you have heaps of runway in front of you [as you would at an RAAF Base] then why would you want to use CAT A...?
Use CAT B and nominate Vtoss, Vy and the Committed Call when you physically can't land on the runway ahead.
Don't cha just love those bloody minded types that tell you ...."you must continue the takeoff and fly around the pattern and land even if there is sufficent runway to land back?
What utter drivel!
A for instance....you are departing Denver Colorado....with a 15,000 foot stretch of concrete in front of you....immediately after CDP....a donk expires without a cough....now with about 14,500 feet of concrete in front of me (150 feet wide)....I elect to follow their edict....and then fly 5-6 minutes on one engine to get around the pattern and land....when all I have to do is lower the collective and make a safe landing.
Talk to me about risk management here. What would their explanation be if they discovered somewhere after the runway falls behind them....that they have a fire as a result of the engine failure? Then what? Oh, but sir we were following the letter of the procedure. Somewhere in all this we are supposed to use some gray matter and exercise our command authority to do what is best during an emergency. The Bloody Minded amongst us forget the lattitude given to us by the Air Regulations during an emergency.
It is a very simple matter to me....if you have a safe landing area in front of you...use it. If not....continue to the very nearest safe area appropriate for landing. If you cannot continue ...you will by natural course of events land whether the area is safe or not.
What utter drivel!
A for instance....you are departing Denver Colorado....with a 15,000 foot stretch of concrete in front of you....immediately after CDP....a donk expires without a cough....now with about 14,500 feet of concrete in front of me (150 feet wide)....I elect to follow their edict....and then fly 5-6 minutes on one engine to get around the pattern and land....when all I have to do is lower the collective and make a safe landing.
Talk to me about risk management here. What would their explanation be if they discovered somewhere after the runway falls behind them....that they have a fire as a result of the engine failure? Then what? Oh, but sir we were following the letter of the procedure. Somewhere in all this we are supposed to use some gray matter and exercise our command authority to do what is best during an emergency. The Bloody Minded amongst us forget the lattitude given to us by the Air Regulations during an emergency.
It is a very simple matter to me....if you have a safe landing area in front of you...use it. If not....continue to the very nearest safe area appropriate for landing. If you cannot continue ...you will by natural course of events land whether the area is safe or not.
Avoid imitations
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Some things to consider!
Why did the engine fail? Is the second one about to expire for the same reason? Fuel contamination? Bird strike? Ice?
Did it go out with a bang? Has the second engine been damaged by the sudden demise of the first? Shouldn't happen these days but it might do.
Might there be a big fuel leak up there and might I be about to light up the sky?
I think the difficulty comes with a runway that is not a very long one. The remaining runway available MIGHT or MIGHT NOT be sufficient to land / stop upon if CDP has gone by a few seconds ago, (effectively our reject performance calculation finished at CDP). However, this is where our individual judgement comes in.
I for one would always prefer to land straight ahead if I thought it could safely be done, rather than flog around the circuit back to the departure point in an aircraft that is designed for two engines but now just has the one.
Just my two penn'orth.....
Why did the engine fail? Is the second one about to expire for the same reason? Fuel contamination? Bird strike? Ice?
Did it go out with a bang? Has the second engine been damaged by the sudden demise of the first? Shouldn't happen these days but it might do.
Might there be a big fuel leak up there and might I be about to light up the sky?
I think the difficulty comes with a runway that is not a very long one. The remaining runway available MIGHT or MIGHT NOT be sufficient to land / stop upon if CDP has gone by a few seconds ago, (effectively our reject performance calculation finished at CDP). However, this is where our individual judgement comes in.
I for one would always prefer to land straight ahead if I thought it could safely be done, rather than flog around the circuit back to the departure point in an aircraft that is designed for two engines but now just has the one.
Just my two penn'orth.....
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What a great question! Let me paraphrase it this way:
"If my engine quits during a Cat A procedure and I am considerably above the CDP, can I still reject if I think I have enough landing area?"
The important answer is:
"Yes, of course, just don't screw it up and run into the bushes."
In a nutshell, nothing replaces the PIC's judgement, not even approved, regimented, stainless procedures.
If you have a failure and have 5000 feet of runway ahead, I think it is dumb to go around. If your buddy says that you must go around, tell him he should be working in McDonald's, where all the tasks are nicely plastic wrapped so that a brain stem is all you need to do the job. Set fries into basket, when red light goes out, dump basket.....
Now, I could be wrong, because I only wrote the procedures, which does not have the same majesty as a Pilot Examiner.
I recall when we wrote the S-76A flight manual emergency procedures, an FAA Test Pilot wanted the chip light procedure re-written to include a sentence where the pilot was instructed "If hovering over a suitable landing area, land" I argued that this could trigger some such words in every procedure, where the conditional cases would create multiple procedures and eventual chaos. We argued for almost 20 minutes when another FAA pilot chimed in, "If the pilot is that dumb that he needs to be told that, no words will save him!" After the laughing died down, we kept the original.
Nothing beats using your brain, and I think Redwine, Sasless and Shy Torque all agree!
"If my engine quits during a Cat A procedure and I am considerably above the CDP, can I still reject if I think I have enough landing area?"
The important answer is:
"Yes, of course, just don't screw it up and run into the bushes."
In a nutshell, nothing replaces the PIC's judgement, not even approved, regimented, stainless procedures.
If you have a failure and have 5000 feet of runway ahead, I think it is dumb to go around. If your buddy says that you must go around, tell him he should be working in McDonald's, where all the tasks are nicely plastic wrapped so that a brain stem is all you need to do the job. Set fries into basket, when red light goes out, dump basket.....
Now, I could be wrong, because I only wrote the procedures, which does not have the same majesty as a Pilot Examiner.
I recall when we wrote the S-76A flight manual emergency procedures, an FAA Test Pilot wanted the chip light procedure re-written to include a sentence where the pilot was instructed "If hovering over a suitable landing area, land" I argued that this could trigger some such words in every procedure, where the conditional cases would create multiple procedures and eventual chaos. We argued for almost 20 minutes when another FAA pilot chimed in, "If the pilot is that dumb that he needs to be told that, no words will save him!" After the laughing died down, we kept the original.
Nothing beats using your brain, and I think Redwine, Sasless and Shy Torque all agree!
Redwine...I just love it when you talk aviation to me! What foreign concepts....we fly in the dark in more ways than the obivious!
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For argument sake you could use the CAT A landing distance/profile chart as a place to start and correlate the data with the CAT A take-off chart to arrive at some reasonably relaible figures in which to argue your point.
I don't have the charts in front of me but I would estimate you could reject from 100 feet and 50 knots when departing from the piano keys of a 3000 foot runway.
I don't have the charts in front of me but I would estimate you could reject from 100 feet and 50 knots when departing from the piano keys of a 3000 foot runway.
A rather thought provoking subject and if I can give a perspective from a Training Captain's standpoint who carries out testing of line pilots every six months during company OPCs as well as LPCs (If you don't recognise the phrases it is becauses it comes out of the Eurospeak dictionary from Euroland i.e. JAR).
Remember that the purpose of any training is to practice (in controlled circumstances) what you would do for real, so most will hopefully appreciate that there is a large element of 'conditioning' shall we say of pilots during check flights that they carry forward into the 'real cockpit' during day to day operations. In fairness this is rightly so, but when some pilots simply do things by wrote (hopefully this is the corret spelling), without the added dimension of 'captaincy, airmanship, CRM, experience, conditions etc. etc.' it can lead to an unwise decision being made. The old saying of "Rules are for the obeyance of fools and the guidance of wise men" springs to mind.
So, when doing check flights I need to see the pilot fly the aircraft in accordance with the approved profiles (CAT A, Class 1 etc.) to ensure that he can and does fly the profile correctly, using Vtoss, MCP/ICP OEI power (or simulated) Vy etc. to provide the safety of flight necessary at all times for the 'passengers' and public that is assured by observing the CAT A minimum operating standards.
So, I need to see a 'reject' as well as a 'flyaway' shall we say for all the 'profiles' that the aircraft is certificated to under CAT A etc.
If I am doing the check flight from an airfield then I have to pre-brief the pilot that he is to assume that he has only got the distances available that he has calculated from his CTOD and RTOD performance graphs for that day and that weight etc. In effect I want him to work to his minimums permitted to force him to fly the appropraite profiles in accordance with the RFM.
I do not want to see 'his interpretation of the way to do things' which flys in the face of all the testing and proving that has been done by far greater pilots that him (and me come to think of it!!).
If I can I try to position the aircaft with a 'sensible' physical obstruction such as a taxiway etc. which provides the pilot with a real limit to his available area to enhance the realistic training perspective - but this is not always available.
If we take LDP's for example, in a lot of aircraft the LDP is a fixed figure in terms of speed and height. Take the AS 355 for example, the LDP for a CAT A Clear Area landing is 100 feet and 40 kts. What if there is a 30 knot wind ? Do you still try to hit the 40 kts figure at LDP - it doesn't feel right it doesn't look right, but it is what the book says, or do you make a Captain's allowance for the strong head wind and increase the LDP to a higher figure of say 50 kts or so.
Initially when converting a pilot onto a new type I make him fly the numbers to get them ingrained. Next check flight, and if the conditions are such that adjusting the figures makes a lot of sense in any man's language and if the pilot wants to make a 'sensible' decision then I cut him the slack and credit him accordingly.
Remember that the purpose of any training is to practice (in controlled circumstances) what you would do for real, so most will hopefully appreciate that there is a large element of 'conditioning' shall we say of pilots during check flights that they carry forward into the 'real cockpit' during day to day operations. In fairness this is rightly so, but when some pilots simply do things by wrote (hopefully this is the corret spelling), without the added dimension of 'captaincy, airmanship, CRM, experience, conditions etc. etc.' it can lead to an unwise decision being made. The old saying of "Rules are for the obeyance of fools and the guidance of wise men" springs to mind.
So, when doing check flights I need to see the pilot fly the aircraft in accordance with the approved profiles (CAT A, Class 1 etc.) to ensure that he can and does fly the profile correctly, using Vtoss, MCP/ICP OEI power (or simulated) Vy etc. to provide the safety of flight necessary at all times for the 'passengers' and public that is assured by observing the CAT A minimum operating standards.
So, I need to see a 'reject' as well as a 'flyaway' shall we say for all the 'profiles' that the aircraft is certificated to under CAT A etc.
If I am doing the check flight from an airfield then I have to pre-brief the pilot that he is to assume that he has only got the distances available that he has calculated from his CTOD and RTOD performance graphs for that day and that weight etc. In effect I want him to work to his minimums permitted to force him to fly the appropraite profiles in accordance with the RFM.
I do not want to see 'his interpretation of the way to do things' which flys in the face of all the testing and proving that has been done by far greater pilots that him (and me come to think of it!!).
If I can I try to position the aircaft with a 'sensible' physical obstruction such as a taxiway etc. which provides the pilot with a real limit to his available area to enhance the realistic training perspective - but this is not always available.
If we take LDP's for example, in a lot of aircraft the LDP is a fixed figure in terms of speed and height. Take the AS 355 for example, the LDP for a CAT A Clear Area landing is 100 feet and 40 kts. What if there is a 30 knot wind ? Do you still try to hit the 40 kts figure at LDP - it doesn't feel right it doesn't look right, but it is what the book says, or do you make a Captain's allowance for the strong head wind and increase the LDP to a higher figure of say 50 kts or so.
Initially when converting a pilot onto a new type I make him fly the numbers to get them ingrained. Next check flight, and if the conditions are such that adjusting the figures makes a lot of sense in any man's language and if the pilot wants to make a 'sensible' decision then I cut him the slack and credit him accordingly.
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The CAT A Confusion.....
For years and years there has been confusion as to what CAT A is all about. And I get the feeling that there is still misunderstanding around the terminology.
Very simply [and I will be simple as Nick is watching] CAT A procedures provide you with a set of procedures and flight profiles that are used to ensure/guarantee [as far as the test data can be trusted] that you can safely fly out of a "Departure Point", or safely land back at the same "Departure Point" should you suffer a OEI situation.
As I said earlier, the "Departure Point" can be a Runway, a Ground Level Heliport or an Elevated Platform....and different profiles apply to each one of them.....refer to the CAT A section of your RFM.
The limiting factor of all these "Departure Points" is how much distance there is in front of you to land or to continue.
The most controversial departure is off a runway. There are CAT A Runway Profiles predicated for various aircraft for runway departures....but why would you use it???
The discussion is normally contaminated when using this profile off a runway, because CAT A assumes that there is only a "Definitive" distance to accelerate / OEI /Reject back on distance available. But then it becomes messy because you’re on a huge long runway, so the whole profile now seems a nonsense.
Let’s look at two other Profiles which make a little more sense!!!
Elevated Platform....Remember the aim is to either land back on to the platform or to safety fly away [Not to land on the ground under and in front the platform...but to fly away]. I don't want to talk about specific helicopter types here, but the profile will include a vertical climb, then at a certain height the helicopter will move away from the Elevated Pad and start to fly away...at that point of forward flight the helicopter has reached CDP. Prior to CDP it has the performance to land back on the Elevated Platform and after CDP, it has the performance to achieve Vtoss and climb away.
Remember the definition of Vtoss: In the OEI configation, with the remaining engine set at the 2.5 minute limits, Vtoss is the speed that will ensure the helicopter will climb at 100 Ft/min.
Don't be confused here with International Offshore Standards.....Oil Platform departures are NOT CAT A...there is NO guarantee that you can clear the platform or clear the water if suffering an OEI...unless you are operating to the much reduced weights of CAT A...and then you will soon go broke?? Offshore Ops are not CAT A.
The most restrictive of all the CAT A's is the level Heliport Departure.
Imagine that you have a Heliport totally surrounded by buildings [houses]....Now you have to fly a profile that will ensure/guarantee you will land back on that small heliport if OEI or have the capacity at any stage after CDP to climb over those houses and safety return to home!...crashing is not an option here, you must have the required performance to fly or you can't fly CAT A from this heliport.
Hence you must get yourself in a position to reach Vtoss....this normally involves a vertical and rearward climb to about 100 -130 ft, so you can always see the landing area. At any stage during the climb that you incur a OEI, then the only place your going is back on that heliport.....don't even think about anything else.
OK, now safely at 130 ft or so, then you smartly move the cyclic forward, that point is CDP. Any OEI after that point is an absolute overshoot, you have no other option as you are past CDP. [If you try to land back, the pad will be to close under you and the fence and the first house will be your final resting place].
Once you dive away, normally 15 - 25 degrees nose down, Vtoss will be achieved and you can then be assured of a flight home!!!
There is always talk of CAT A....but really it is a rare event in most pilots lives....CAT B is 99.9% of your life.
I would think the most obvious folk that would use CAT A is EMS chaps going into and coming out of congested inner Suburban Hospital pads.
But at what cost..?? To achieve these CAT A profiles the extra performance must come from somewhere???...that means a reduction in MTOW to enable the profiles to be flown.
Todays aviation world demands us to haul as much payload as possible, so CAT A unless specifically required is very seldom used.
[And talked about to much!!]
Very simply [and I will be simple as Nick is watching] CAT A procedures provide you with a set of procedures and flight profiles that are used to ensure/guarantee [as far as the test data can be trusted] that you can safely fly out of a "Departure Point", or safely land back at the same "Departure Point" should you suffer a OEI situation.
As I said earlier, the "Departure Point" can be a Runway, a Ground Level Heliport or an Elevated Platform....and different profiles apply to each one of them.....refer to the CAT A section of your RFM.
The limiting factor of all these "Departure Points" is how much distance there is in front of you to land or to continue.
The most controversial departure is off a runway. There are CAT A Runway Profiles predicated for various aircraft for runway departures....but why would you use it???
The discussion is normally contaminated when using this profile off a runway, because CAT A assumes that there is only a "Definitive" distance to accelerate / OEI /Reject back on distance available. But then it becomes messy because you’re on a huge long runway, so the whole profile now seems a nonsense.
Let’s look at two other Profiles which make a little more sense!!!
Elevated Platform....Remember the aim is to either land back on to the platform or to safety fly away [Not to land on the ground under and in front the platform...but to fly away]. I don't want to talk about specific helicopter types here, but the profile will include a vertical climb, then at a certain height the helicopter will move away from the Elevated Pad and start to fly away...at that point of forward flight the helicopter has reached CDP. Prior to CDP it has the performance to land back on the Elevated Platform and after CDP, it has the performance to achieve Vtoss and climb away.
Remember the definition of Vtoss: In the OEI configation, with the remaining engine set at the 2.5 minute limits, Vtoss is the speed that will ensure the helicopter will climb at 100 Ft/min.
Don't be confused here with International Offshore Standards.....Oil Platform departures are NOT CAT A...there is NO guarantee that you can clear the platform or clear the water if suffering an OEI...unless you are operating to the much reduced weights of CAT A...and then you will soon go broke?? Offshore Ops are not CAT A.
The most restrictive of all the CAT A's is the level Heliport Departure.
Imagine that you have a Heliport totally surrounded by buildings [houses]....Now you have to fly a profile that will ensure/guarantee you will land back on that small heliport if OEI or have the capacity at any stage after CDP to climb over those houses and safety return to home!...crashing is not an option here, you must have the required performance to fly or you can't fly CAT A from this heliport.
Hence you must get yourself in a position to reach Vtoss....this normally involves a vertical and rearward climb to about 100 -130 ft, so you can always see the landing area. At any stage during the climb that you incur a OEI, then the only place your going is back on that heliport.....don't even think about anything else.
OK, now safely at 130 ft or so, then you smartly move the cyclic forward, that point is CDP. Any OEI after that point is an absolute overshoot, you have no other option as you are past CDP. [If you try to land back, the pad will be to close under you and the fence and the first house will be your final resting place].
Once you dive away, normally 15 - 25 degrees nose down, Vtoss will be achieved and you can then be assured of a flight home!!!
There is always talk of CAT A....but really it is a rare event in most pilots lives....CAT B is 99.9% of your life.
I would think the most obvious folk that would use CAT A is EMS chaps going into and coming out of congested inner Suburban Hospital pads.
But at what cost..?? To achieve these CAT A profiles the extra performance must come from somewhere???...that means a reduction in MTOW to enable the profiles to be flown.
Todays aviation world demands us to haul as much payload as possible, so CAT A unless specifically required is very seldom used.
[And talked about to much!!]
nicely said
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Engine Failure After CDP
tbc and Red Wine,
Thanks ever so much for your imput, I value both your well argued propositions and the insight embodied in the argument. I recommend the CRM site mentioned by Pepi as well.
Blue Skies, Brian
Thanks ever so much for your imput, I value both your well argued propositions and the insight embodied in the argument. I recommend the CRM site mentioned by Pepi as well.
Blue Skies, Brian
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The problem that was originally put forward has to do with having lots of runway available ahead of you- probably more than the CAT A data had assumed.
One helicopter I know has a definition of a long runway as bewteen 1100 and 1700 feet in length. Not much help if you are in front of a 10,000' runway to be sure.
The best advice I could give is to consider using the landing distance for the 'long runway' case, as a guide. But then what do you do to make sure you can decelerate and stop in that distance - maintain some slow airspeed and low height above ground until you are sure you couldn't make it? That's not smart either.
Yet another place where we are nowhere as cut and dried as our fixed wing brethern. And another place where we need some reasonable guidance.
But why are we taking off from runways anyway? That's like making all trucks load and unload at railway stations...
One helicopter I know has a definition of a long runway as bewteen 1100 and 1700 feet in length. Not much help if you are in front of a 10,000' runway to be sure.
The best advice I could give is to consider using the landing distance for the 'long runway' case, as a guide. But then what do you do to make sure you can decelerate and stop in that distance - maintain some slow airspeed and low height above ground until you are sure you couldn't make it? That's not smart either.
Yet another place where we are nowhere as cut and dried as our fixed wing brethern. And another place where we need some reasonable guidance.
But why are we taking off from runways anyway? That's like making all trucks load and unload at railway stations...
I recall this being discussed here a couple of years ago.
The whole point of training pilots how to fly Cat A profiles correctly, is that when an engine failure occurs for real, they will react instinctively and appropriately for the circumstances. As was mentioned earlier, the assumption in training has to be that minimum distances are available so that the pilot response mirrors the actions used during the certification. These may well be fairly dynamic actions, and in the context of a 10,000 ft runway, seem unnecessary.
If you become accustomed to carrying out gentle flares, followed by a moderate run on with out Nr droop, when rejecting a take off, becasue you have loads of runway, that will become your conditioned response. It might feel comfortable, and the slick 'greasers' may boost your ego, but come the day you have the minimum distance available, you will have to change your response and effectively make it up as you go along. Throw in the inevitable pause for thought follwing an unexpected failure, and there's a good chance you'll end up off the reject area.
So, the reject case is fairly straight forward and is mirrored by the landing case too. The continued case is less clear. Again, you have to be able to train a conditioned response, so that a pilot can carry out a safe continued take off from CDP/TDP on one engine. Bearing in mind the pitifully low rates of climb that will be achieved, and the relative skill required to achieve them, this is essential training.
What is unclear is how and when the piot is able to determine he can safely reject a take off having passed CDP/TDP. The further on he has gone, the more difficult the reject will be and the further away from what he has experienced in training it will be. In a two crew a/c there may well be differences in opinion as to when this point is reached, also. For these reasons, I think it is very dodgy ground to start talking about commital points after reaching CDP/TDP.
However, common sense must prevail and I don't believe anyone is trying to counter that. To my mind, if you take off from a short strip with a hostile environment bordering it, and have an engine failure after CDP/TDP, you will climb away and probably execute a circuit back to where you have just taken off from. Other than continue elsewhere, this is the only sensible option. However, if you take off from a large aiport and still have several thousand feet of runway ahead then, following the initial correct actions required to establish an OEI climb, it would seem quite logical to elect to land ahead. Effectively this is the same but without flying a circuit.
At the end of the day, CDP/TDP is only a guide as to what is or is not possible and your actions should be guided by this information. Prior to it you cannot fly away (not with any guarantees, anyway) after it you can. Simple as that.
What you choose to do on the day is up to you, but make sure you have a good reason to contradict the flight manual/training received, and try to understand the logic of how Cat A training is administered. It is not done that way to show you that Training Captains have no imagination or brains; it is done to put you in the best position come the unfortunate day you have a failure at a critical point in the least favourable situation.
The whole point of training pilots how to fly Cat A profiles correctly, is that when an engine failure occurs for real, they will react instinctively and appropriately for the circumstances. As was mentioned earlier, the assumption in training has to be that minimum distances are available so that the pilot response mirrors the actions used during the certification. These may well be fairly dynamic actions, and in the context of a 10,000 ft runway, seem unnecessary.
If you become accustomed to carrying out gentle flares, followed by a moderate run on with out Nr droop, when rejecting a take off, becasue you have loads of runway, that will become your conditioned response. It might feel comfortable, and the slick 'greasers' may boost your ego, but come the day you have the minimum distance available, you will have to change your response and effectively make it up as you go along. Throw in the inevitable pause for thought follwing an unexpected failure, and there's a good chance you'll end up off the reject area.
So, the reject case is fairly straight forward and is mirrored by the landing case too. The continued case is less clear. Again, you have to be able to train a conditioned response, so that a pilot can carry out a safe continued take off from CDP/TDP on one engine. Bearing in mind the pitifully low rates of climb that will be achieved, and the relative skill required to achieve them, this is essential training.
What is unclear is how and when the piot is able to determine he can safely reject a take off having passed CDP/TDP. The further on he has gone, the more difficult the reject will be and the further away from what he has experienced in training it will be. In a two crew a/c there may well be differences in opinion as to when this point is reached, also. For these reasons, I think it is very dodgy ground to start talking about commital points after reaching CDP/TDP.
However, common sense must prevail and I don't believe anyone is trying to counter that. To my mind, if you take off from a short strip with a hostile environment bordering it, and have an engine failure after CDP/TDP, you will climb away and probably execute a circuit back to where you have just taken off from. Other than continue elsewhere, this is the only sensible option. However, if you take off from a large aiport and still have several thousand feet of runway ahead then, following the initial correct actions required to establish an OEI climb, it would seem quite logical to elect to land ahead. Effectively this is the same but without flying a circuit.
At the end of the day, CDP/TDP is only a guide as to what is or is not possible and your actions should be guided by this information. Prior to it you cannot fly away (not with any guarantees, anyway) after it you can. Simple as that.
What you choose to do on the day is up to you, but make sure you have a good reason to contradict the flight manual/training received, and try to understand the logic of how Cat A training is administered. It is not done that way to show you that Training Captains have no imagination or brains; it is done to put you in the best position come the unfortunate day you have a failure at a critical point in the least favourable situation.
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Having flown both sides of the farm, FAA & JAA, Cat A, Cat B and A/S over Alt on a SE from a forty story building downtown Denver, Colorado, ...I'm amazed at the amount of 'Woffle, Crap & Semantics' that can be discussed out of the attributes of Cat A profiles. But then thats what makes this forum fun!!! I have yet to meet two pilots which will employ the exact same techniques and consider the same area's on the same type Heli to achieve the same result. As a previous reply on this thread stated...at the end of the day the PIC will do whatever his common sense and collective experiance will allow him to do prior to or after CDP to remain in control of the heli!
It's like the merits of the available wind and gust factor being
considered by the second for absolute accuracy!!
If you have Tq applied right or left, depending on the country of manufacture, how many degrees HDG do you offset your rearward position climb on a Helideck ( 3 meters or higher) 80' to 130', based on ability to load rotor on engine failure assuming the other one won't cough! Are you seriously going to mull over the other one failing due to fuel contamination when you are just dealing with the present situation and keeping the machine in one piece!!! It's great for training and even refresher recurrency....to get the basic concept across......mechanical or otherwise, but each pilot will no doubt, make their own determination as to what they need to do. If they bang it up in the process in the unlikely event, well they should at least be able to account for their actions professionally! There we all go by the grace of God in our careers, or by simply becoming experianced and more reserved as the hours tick by!
It's like the merits of the available wind and gust factor being
considered by the second for absolute accuracy!!
If you have Tq applied right or left, depending on the country of manufacture, how many degrees HDG do you offset your rearward position climb on a Helideck ( 3 meters or higher) 80' to 130', based on ability to load rotor on engine failure assuming the other one won't cough! Are you seriously going to mull over the other one failing due to fuel contamination when you are just dealing with the present situation and keeping the machine in one piece!!! It's great for training and even refresher recurrency....to get the basic concept across......mechanical or otherwise, but each pilot will no doubt, make their own determination as to what they need to do. If they bang it up in the process in the unlikely event, well they should at least be able to account for their actions professionally! There we all go by the grace of God in our careers, or by simply becoming experianced and more reserved as the hours tick by!
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Red Wine
Excellent post.....
I can't really believe all the confusion....
For any profile it should be a simple decision. "Land back if you can" or "fly if you have to".
212 man
From the twins that I have flown there is no reason to be abrupt with control inputs to accomplish a safe reject unless of course you have not calculated correctly (weights and distances) to begin with.
These profiles have been designed to be flown by the lowest common denominator pilot.....it must be true because I can fly them.
Cheers & Merry Xmas
Excellent post.....
I can't really believe all the confusion....
For any profile it should be a simple decision. "Land back if you can" or "fly if you have to".
212 man
From the twins that I have flown there is no reason to be abrupt with control inputs to accomplish a safe reject unless of course you have not calculated correctly (weights and distances) to begin with.
These profiles have been designed to be flown by the lowest common denominator pilot.....it must be true because I can fly them.
Cheers & Merry Xmas
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I feel that the going backwards to achieve the cat A reject (rooftop pad) is very scary.. The chances of hitting something while "reversing" and climbing are much greater than the chances of an engine failure.
As an EMS pilot, having seen all the ****e around hospital pads, backwards is not the smartest option. The same applies to scene operations...
As an EMS pilot, having seen all the ****e around hospital pads, backwards is not the smartest option. The same applies to scene operations...
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Merry Xmas All.....
As its Chrissy Day I'm not going to beat my chest here......
But CAT A is CAT A....fly the profiles or don't....there is no room for the normal Helicopter flexibility here....The profiles, heights and speeds are tested proven and they work.
Don't whatever you do, vary a solid procedure with an individuals belief that there are better variants. That is why CAT A is a certified FMS in your RFM.
C4...Backing back is your only option if doing CAT A in a BK117, whereas the same CAT A in an B412EP will have you coming off the side of the platform.....not sure what you fly, but your RFM will dictate to you what profile you must fly to conform to CAT A.....
ANYTHING else is not CAT A.
Please don't confuse this issue, its been confusing the Industry for years.
If you look at the rearward distance compared with your vertical height, you will find that as you have kept the landing area in your chin bubble [Yes a very steep rearward climb] you will still be over your same building. Bearing in mind you probably just flew a CAT A approach to the same pad.
CAT A is just that...CAT A, any variance to that is not!!!
But CAT A is CAT A....fly the profiles or don't....there is no room for the normal Helicopter flexibility here....The profiles, heights and speeds are tested proven and they work.
Don't whatever you do, vary a solid procedure with an individuals belief that there are better variants. That is why CAT A is a certified FMS in your RFM.
C4...Backing back is your only option if doing CAT A in a BK117, whereas the same CAT A in an B412EP will have you coming off the side of the platform.....not sure what you fly, but your RFM will dictate to you what profile you must fly to conform to CAT A.....
ANYTHING else is not CAT A.
Please don't confuse this issue, its been confusing the Industry for years.
If you look at the rearward distance compared with your vertical height, you will find that as you have kept the landing area in your chin bubble [Yes a very steep rearward climb] you will still be over your same building. Bearing in mind you probably just flew a CAT A approach to the same pad.
CAT A is just that...CAT A, any variance to that is not!!!
Last edited by Red Wine; 25th Dec 2003 at 20:20.
Redwine....get 212Man to explain the Bristow Nigeria 212 Takeoff profiles to you....then see if Cat A is really Cat A?
Avoid imitations
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Cat A is Cat A.....
Yes, but the helipad profile is designed to get the aircraft back onto a pad of a defined minimum size. The backwards movement is there so the pilot can keep the LP in view, it's not there for performance considerations in the strictest sense.
If there is more space ahead than the minimum specified / required and it's not critical to land back on in exactly the same place, then it makes little sense to go backwards, particularly if there are obstructions behind the aircraft.
Yes, but the helipad profile is designed to get the aircraft back onto a pad of a defined minimum size. The backwards movement is there so the pilot can keep the LP in view, it's not there for performance considerations in the strictest sense.
If there is more space ahead than the minimum specified / required and it's not critical to land back on in exactly the same place, then it makes little sense to go backwards, particularly if there are obstructions behind the aircraft.
