Escape routes for light a/c
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Escape routes for light a/c
G'day guys,
This questions might sound stupid, but can light a/c ie <5700 Kgs, with adequate climb performance use the airline special rwy escape procedures? (not CAO 20.7.1b)
Or are these only suitable for the actual a/c to be factored for the procedure???
Also do some G/A guys use these charts in a/c ops like a B200, EMB 110, DHC 6, B58, C404 and the like even thought THEY are not certified for the a/c, but the a/c can get airborne and stay airborne?
Always asked IFR instructors there thoughts on escape routes, many have said you've just got to circle up to MSA for terrain protection within your circling area catergory and look with your own eye at the terrain within the terminal area???.
Any good thoughts on how to build a home made procedure or have an idea what to do when the sh*t hits the fan???? (loss of perf in a 20.7.4 or 20.7.2 and 20.7.1b machine, with no company resources to build or finance for data to be collected for a special procedure.
thanks,
DW.
This questions might sound stupid, but can light a/c ie <5700 Kgs, with adequate climb performance use the airline special rwy escape procedures? (not CAO 20.7.1b)
Or are these only suitable for the actual a/c to be factored for the procedure???
Also do some G/A guys use these charts in a/c ops like a B200, EMB 110, DHC 6, B58, C404 and the like even thought THEY are not certified for the a/c, but the a/c can get airborne and stay airborne?
Always asked IFR instructors there thoughts on escape routes, many have said you've just got to circle up to MSA for terrain protection within your circling area catergory and look with your own eye at the terrain within the terminal area???.
Any good thoughts on how to build a home made procedure or have an idea what to do when the sh*t hits the fan???? (loss of perf in a 20.7.4 or 20.7.2 and 20.7.1b machine, with no company resources to build or finance for data to be collected for a special procedure.
thanks,
DW.
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G'day DW,
I can't see any reason why Bloggs in his Aztruck can't utilise such procedures.......It is after all up to the PIC to ensure terrain clearance!
Anyhow, I believe it's required for RPT ops, as an operator I flew for used "escape procedures" in PA31 RPT ops.
Having said this though......one couldn't expect to use procedures designed for say a Metro in a type with significantly different one-inop performance. It wouldn't be highly unreasonable though to have a "one size fits all" procedure designed for the majority of piston twins though.
I'm not exactly sure of the context in which the question was asked but I hope I've managed to shed some light???
RFKB
I can't see any reason why Bloggs in his Aztruck can't utilise such procedures.......It is after all up to the PIC to ensure terrain clearance!
Anyhow, I believe it's required for RPT ops, as an operator I flew for used "escape procedures" in PA31 RPT ops.
Having said this though......one couldn't expect to use procedures designed for say a Metro in a type with significantly different one-inop performance. It wouldn't be highly unreasonable though to have a "one size fits all" procedure designed for the majority of piston twins though.
I'm not exactly sure of the context in which the question was asked but I hope I've managed to shed some light???
RFKB
Bloody good discussion point.
It certainly gets you thinking, having to fly in the 'grey area' between the extremes of having one engine, giving you the clear-cut option of crashing ahead, or the happy situation of operating a machine that can climb like a homesick angel on one.
I reckon pilots of IFR light twins have one of the most difficult jobs around safety-wise if they're to cover their bases appropriately, so to speak.
My 2 bobs would be that escape procedures worked out by other types would possibly be OK as a guide, but you'd have to know their assumptions, eg climb gradient made good on 1 engine, to work out if they would be any good for you.
I don't see anything wrong with using not only your own circling area, but those of categories bigger than you, eg if you're Cat B, then use any of the other boundaries and heights for C, D, E when climbing in the circling area. I mean, if you can get up to Cat E height you've got a bloody big area to climb in once you get the aircraft turned around and established in it.
Having said all that, if it's a familiar airfield, I don't reckon there is any substitute for the warm and fuzzy feeling of having a few escape routes worked out on a nice VMC day for use when things go wrong. When taking off visually, just have a look around at where your SID or whatever goes, and where you could head if you were in the sad situation of only just making the ridiculously low climb gradients we can expect on one engine from some of the machines around the place.
It certainly gets you thinking, having to fly in the 'grey area' between the extremes of having one engine, giving you the clear-cut option of crashing ahead, or the happy situation of operating a machine that can climb like a homesick angel on one.
I reckon pilots of IFR light twins have one of the most difficult jobs around safety-wise if they're to cover their bases appropriately, so to speak.
My 2 bobs would be that escape procedures worked out by other types would possibly be OK as a guide, but you'd have to know their assumptions, eg climb gradient made good on 1 engine, to work out if they would be any good for you.
I don't see anything wrong with using not only your own circling area, but those of categories bigger than you, eg if you're Cat B, then use any of the other boundaries and heights for C, D, E when climbing in the circling area. I mean, if you can get up to Cat E height you've got a bloody big area to climb in once you get the aircraft turned around and established in it.
Having said all that, if it's a familiar airfield, I don't reckon there is any substitute for the warm and fuzzy feeling of having a few escape routes worked out on a nice VMC day for use when things go wrong. When taking off visually, just have a look around at where your SID or whatever goes, and where you could head if you were in the sad situation of only just making the ridiculously low climb gradients we can expect on one engine from some of the machines around the place.
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There's no reason a piston twin driver can't use an escape proceedure designed for a turbine aircraft. The problem is that as far as I know a piston twin weighing less than 5700 KG only has to be able to maintain 5000ft with one inop. No requirement to have any sort of climb gradient if one fails after takeoff. The escape proceedures are calculated on a minimum climb gradient, usually 2.4%. Aside from a Barron on a cold day I cannot think of any piston twin that would meet this requirement.
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The escapes are normally calculated using a 1.6% climb gradient for a twin.
That is 97 ft per nm. So where the MSA's are high, it takes a lot of track miles to get there.
Here is a question that always get a number of different answers.
Which has the higher rate of climb - a Boeing 737-800 with 26k engines which is empty and climbing at 2.4% or a B737-800 with 24k engines that is fully loaded (and climbing at 2.4%)....
Silly question I know!
That is 97 ft per nm. So where the MSA's are high, it takes a lot of track miles to get there.
Here is a question that always get a number of different answers.
Which has the higher rate of climb - a Boeing 737-800 with 26k engines which is empty and climbing at 2.4% or a B737-800 with 24k engines that is fully loaded (and climbing at 2.4%)....
Silly question I know!
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All light twins <5700 kg are supposed to be able to achieve a 1% climb to 5000 under ISA. Above 5700 its is 2.4% for transport category or 2.0% for commuters.
Theses figures are reduced by 0.8% for the transport and commuter category so a metro should achieve 2% but all obsticles need to be below 1.2% gradient. This allows fro performance drops with age of the A/C and pilot skill levels.
So for a lightly loaded navajo in tasmania in winter there is a resonable chance that they could fly the same escape procedure as a metro and not hit anything, however I would not want to be in cloud hoping that I would miss.
CAO 20.7.4 12.2 quotes:
An aeroplane must be operated in accordance with the procedures and limitations specified in the Aeroplane Flight Manual. An operator of a multiengined aeroplane engaged in charter operations or aerial work operations must
include in his or her Operations Manual the procedures to be followed by a pilot in the event of engine failure.
So if the operator chooses not to provide any written procedures then they are laible if the ---- hits the fan and one engine does stop.
The best people to talk to about a particular airport are the owners of the airports as with the new CASR's coming in soon they are going to need to do obsticle charts and so all operators should be able to get a copy and then use some basic maths to set a procedure in place.
Theses figures are reduced by 0.8% for the transport and commuter category so a metro should achieve 2% but all obsticles need to be below 1.2% gradient. This allows fro performance drops with age of the A/C and pilot skill levels.
So for a lightly loaded navajo in tasmania in winter there is a resonable chance that they could fly the same escape procedure as a metro and not hit anything, however I would not want to be in cloud hoping that I would miss.
CAO 20.7.4 12.2 quotes:
An aeroplane must be operated in accordance with the procedures and limitations specified in the Aeroplane Flight Manual. An operator of a multiengined aeroplane engaged in charter operations or aerial work operations must
include in his or her Operations Manual the procedures to be followed by a pilot in the event of engine failure.
So if the operator chooses not to provide any written procedures then they are laible if the ---- hits the fan and one engine does stop.
The best people to talk to about a particular airport are the owners of the airports as with the new CASR's coming in soon they are going to need to do obsticle charts and so all operators should be able to get a copy and then use some basic maths to set a procedure in place.
PPRuNeaholic
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I've been stuck on this bit, from the originating post...
There's a very big assumption here, that the pilot will be instantly ready to react, so that yaw is minimised and the aircraft leaves the ground before it leaves the runway. If not, then all bets are off.
Yes, the pilot SHOULD be ready for it on each and every take-off. But consider this... the pilot flies the same aircraft every day of his roster period. It never lets him down on take-off... until the one day when, in the latter part of a 10-sector day, it actually DOES let him down. How ready is he likely to be?
We're not talking rules here, we're talking real world human nature. I suspect that the chances of actually getting airborne, safely are pretty remote, especially with any semblance of a realistic payload.
I guess that my underlying problem with this is that, where I operate, most strips are pretty bloody short. Therefore we get used to things like... engine failure before wheels up - we're gunna crash over (pointing...) there! We also have temperature and altitude problems that add to the problem, so we don't have a lot of choice if an engine fails in a light twin before the wheels are in the well.
Of course, once the wheels are up, there are some options but, again, the pilot needs to be very VERY alert. And, as already said, if he's into the 8th sector of a 10-sector day, there's a chance that he mightn't be as ready as he should be.
I believe in having an escape route for those situations that may occur after the aeroplane is cleaned up, but I seriously doubt that any light twin in this country could realistically follow the escape route applicable to a larger aeroplane. It's more a case of "horses for courses", IMHO.
Also do some G/A guys use these charts in a/c ops like a B200, EMB 110, DHC 6, B58, C404 and the like even thought THEY are not certified for the a/c, but the a/c can get airborne and stay airborne?
Yes, the pilot SHOULD be ready for it on each and every take-off. But consider this... the pilot flies the same aircraft every day of his roster period. It never lets him down on take-off... until the one day when, in the latter part of a 10-sector day, it actually DOES let him down. How ready is he likely to be?
We're not talking rules here, we're talking real world human nature. I suspect that the chances of actually getting airborne, safely are pretty remote, especially with any semblance of a realistic payload.
I guess that my underlying problem with this is that, where I operate, most strips are pretty bloody short. Therefore we get used to things like... engine failure before wheels up - we're gunna crash over (pointing...) there! We also have temperature and altitude problems that add to the problem, so we don't have a lot of choice if an engine fails in a light twin before the wheels are in the well.
Of course, once the wheels are up, there are some options but, again, the pilot needs to be very VERY alert. And, as already said, if he's into the 8th sector of a 10-sector day, there's a chance that he mightn't be as ready as he should be.
I believe in having an escape route for those situations that may occur after the aeroplane is cleaned up, but I seriously doubt that any light twin in this country could realistically follow the escape route applicable to a larger aeroplane. It's more a case of "horses for courses", IMHO.
Moderator
downwind,
One of the site rules is that a post should be made once only. By my observation you have posted this in at least three separate forum locations. Could we ask that, in future, you pick the place you think most appropriate and run with the one instance of the question ....
If I might speak to several points where there are elements of dangerous thinking ..
(a) while a GA pilot is responsible for all sorts of things, given the paucity of information available to him/her, it is not at all easy for him/her to ensure that the lumpy bits are avoided OEI in IMC .. and even in VMC.
(b) there certainly are "escape" procedures published by LCRPT operators ... many of which are not worth the paper on which they are written .. a problem belonga CASA which doesn't have enough people competent in this area ... those who are there do the best they can but, at the end of the day, there are not enough hours in the day ...
(c) "one size fits all" is most certainly not feasible as there are just too many variables in the typical analysis.
(d) using another procedure as a guide requires that you have a detailed understanding of the considerations which went into the procedure's design ... speeds, gradient capability, turn radius if appropriate, acceleration height and distance, etc ...
(e) using the circling area data is of use, provided that you know the clearance from, and the location of the critical circling obstacle. The former can vary quite a bit from aerodrome to aerodrome as well as cat to cat. The main problem is getting the aircraft to a suitable height and then turning ... while remaining in the circling area or getting back into it without hitting something during the turn outside it .... often not an easy calculation. If you are fortunate enough to have a failure well within the circling area and at a height well above the critical obstacle, then good for you ... it was your lucky day.
(f) eyeballing the escape is almost never a workable solution as the achieved OEI gradients are often so shallow that the pilot is not able to make any sensible assessments from the cockpit .. ie it is generally only feasible to do the sums in the office and, if you wish, then simulate the predicted gradients and fly a test exercise to see just how low it all is ....
(g) be very wary of presuming aircraft capabilities. Particularly with the move to US rules, we now have a variety of data floating around based on quite different rules .... the older Australian rules sometimes were more, and sometimes less, conservative than the US rules .... Unless you are very certain of your facts, be very, very wary of presuming that the Bugsmasher Mk I will do this or that in the event of an OEI situation.
(h) big iron escape procedures will be designed on gradients which are not less than the airworthiness WAT limits (eg 2.4 gross, 1.6 net, second segment, in the case of a big twin) but may well be considerably higher (by imposing RTOW restrictions) to achieve the necessary clearance from obstacles for the particular runway departure. Generally, it is reasonable to presume that the WAT limits will only apply for comparatively long runways without much in the way of obstacle problems.
(i) you can make most any light twin outperform the big bird's climb performance .. just reduce the weight. THe problem arises when the failure occurs with a full load on a hot and high take off ... when you can't beat anything. ... and just try asking your passengers to leave by the rear exit to improve your position ...
(j) the question about the 738s is not silly at all ... just a matter of remembering that, for the same gradient, the ROC increases with TAS. Now, it would have been more interesting to have posed the question "what thrust setting would be necessary to ... " The question, as posed of course, is set up to trap those who don't take a few seconds to think about the question ...
(k) be very wary of reading too much into the CAO 20 series as these are operational CAOs, not airworthiness... a few problems if you delve too deeply ...
(l) Ozex's pragmatic views on life are worth taking on board ...
Overall, it is not a simple situation to consider ...
(a) the lack of realistic data for the lightie,
(b) the often seen irresponsible attitude of management,
(c) the difficulty of getting accurate obstacle data,
(d) the number of people around who think they know a lot more than they do in respect of aircraft performance
etc, etc, .....
makes simplistic approaches to the problem potentially very dangerous ....
Monday morning rant over ..... but do be careful out there, people ... physical intimacy with rocks in cloud might spoil your day big time ..
One of the site rules is that a post should be made once only. By my observation you have posted this in at least three separate forum locations. Could we ask that, in future, you pick the place you think most appropriate and run with the one instance of the question ....
If I might speak to several points where there are elements of dangerous thinking ..
(a) while a GA pilot is responsible for all sorts of things, given the paucity of information available to him/her, it is not at all easy for him/her to ensure that the lumpy bits are avoided OEI in IMC .. and even in VMC.
(b) there certainly are "escape" procedures published by LCRPT operators ... many of which are not worth the paper on which they are written .. a problem belonga CASA which doesn't have enough people competent in this area ... those who are there do the best they can but, at the end of the day, there are not enough hours in the day ...
(c) "one size fits all" is most certainly not feasible as there are just too many variables in the typical analysis.
(d) using another procedure as a guide requires that you have a detailed understanding of the considerations which went into the procedure's design ... speeds, gradient capability, turn radius if appropriate, acceleration height and distance, etc ...
(e) using the circling area data is of use, provided that you know the clearance from, and the location of the critical circling obstacle. The former can vary quite a bit from aerodrome to aerodrome as well as cat to cat. The main problem is getting the aircraft to a suitable height and then turning ... while remaining in the circling area or getting back into it without hitting something during the turn outside it .... often not an easy calculation. If you are fortunate enough to have a failure well within the circling area and at a height well above the critical obstacle, then good for you ... it was your lucky day.
(f) eyeballing the escape is almost never a workable solution as the achieved OEI gradients are often so shallow that the pilot is not able to make any sensible assessments from the cockpit .. ie it is generally only feasible to do the sums in the office and, if you wish, then simulate the predicted gradients and fly a test exercise to see just how low it all is ....
(g) be very wary of presuming aircraft capabilities. Particularly with the move to US rules, we now have a variety of data floating around based on quite different rules .... the older Australian rules sometimes were more, and sometimes less, conservative than the US rules .... Unless you are very certain of your facts, be very, very wary of presuming that the Bugsmasher Mk I will do this or that in the event of an OEI situation.
(h) big iron escape procedures will be designed on gradients which are not less than the airworthiness WAT limits (eg 2.4 gross, 1.6 net, second segment, in the case of a big twin) but may well be considerably higher (by imposing RTOW restrictions) to achieve the necessary clearance from obstacles for the particular runway departure. Generally, it is reasonable to presume that the WAT limits will only apply for comparatively long runways without much in the way of obstacle problems.
(i) you can make most any light twin outperform the big bird's climb performance .. just reduce the weight. THe problem arises when the failure occurs with a full load on a hot and high take off ... when you can't beat anything. ... and just try asking your passengers to leave by the rear exit to improve your position ...
(j) the question about the 738s is not silly at all ... just a matter of remembering that, for the same gradient, the ROC increases with TAS. Now, it would have been more interesting to have posed the question "what thrust setting would be necessary to ... " The question, as posed of course, is set up to trap those who don't take a few seconds to think about the question ...
(k) be very wary of reading too much into the CAO 20 series as these are operational CAOs, not airworthiness... a few problems if you delve too deeply ...
(l) Ozex's pragmatic views on life are worth taking on board ...
Overall, it is not a simple situation to consider ...
(a) the lack of realistic data for the lightie,
(b) the often seen irresponsible attitude of management,
(c) the difficulty of getting accurate obstacle data,
(d) the number of people around who think they know a lot more than they do in respect of aircraft performance
etc, etc, .....
makes simplistic approaches to the problem potentially very dangerous ....
Monday morning rant over ..... but do be careful out there, people ... physical intimacy with rocks in cloud might spoil your day big time ..
Last edited by john_tullamarine; 9th Jun 2003 at 08:26.
Moderator
plenty of threads on the subject if you care to do a search ... providing your speed is adequate it really doesn't matter all that much .... old wives' tales notwithstanding ...
