Limiting Factors For Takeoff
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state-of-the-art birds that track LNAV while rolling and are ready to engage runway track on lift off
Now do these use the autopilot to perform the takeoff or does Capt Pilot still do the initial bit ? If so, then we still have the problem of tracking integrity during a critical failure prior to autopilot engagement.
it is a bad airport, indeed, that has that type of close-in obstacle environment just beyond 300 feet each side of the DER.
.. and places where the runway points through a close in saddle or has an isolated close in hill feature with surrounding terrain necessitating an early turn either inside or around the hill ... not at all rare.
Now do these use the autopilot to perform the takeoff or does Capt Pilot still do the initial bit ? If so, then we still have the problem of tracking integrity during a critical failure prior to autopilot engagement.
it is a bad airport, indeed, that has that type of close-in obstacle environment just beyond 300 feet each side of the DER.
.. and places where the runway points through a close in saddle or has an isolated close in hill feature with surrounding terrain necessitating an early turn either inside or around the hill ... not at all rare.
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j_t
Training must have really gone down hill. We were required to keep it tracking on runway leading (and 767 runway track) especially during rotation and establishing V2 to V2 + 10. If not we remained for training.
.. and places where the runway points through a close in saddle or has an isolated close in hill feature with surrounding terrain necessitating an early turn either inside or around the hill ... not at all rare.
Some examples? Any in the U.S. Airports where 737 type aircraft operate?
Now do these use the autopilot to perform the takeoff or does Capt Pilot still do the initial bit ? If so, then we still have the problem of tracking integrity during a critical failure prior to autopilot engagement.
WR: it is a bad airport, indeed, that has that type of close-in obstacle environment just beyond 300 feet each side of the DER.
.. and places where the runway points through a close in saddle or has an isolated close in hill feature with surrounding terrain necessitating an early turn either inside or around the hill ... not at all rare.
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Hi aterpster,
I don't know about any US airports - but ACE - GCRR - Lanzarote in the Canary Islands has an engine out procedure from Rwy 03 that says something like "At 60 feet (I'll say that again sixty feet) - Right Turn 090 degs".
(Min height for turn = 1.5 * wing span)
I've taken L1011s & A320s in there.
I don't know about any US airports - but ACE - GCRR - Lanzarote in the Canary Islands has an engine out procedure from Rwy 03 that says something like "At 60 feet (I'll say that again sixty feet) - Right Turn 090 degs".
(Min height for turn = 1.5 * wing span)
I've taken L1011s & A320s in there.
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QNH and Wind Tolerances
Slightly off topic, but could not find answers to these couple of questions?
QNH (Altimeter) tolerances for a RTOW calculation. If I am lined up to go and the altimeter setting drops 1 mb, am I covered? My company uses a 2 mb tolerance for reduced thrust TO, but is there a required tolerance for Max Thrust TO calcualtions?
Also I recall from Perf A that the headwind is factored by 50% and the tailwind by 150%. So what does this really mean. (ie what if I have 10 knots vs 0 knots?)
QNH (Altimeter) tolerances for a RTOW calculation. If I am lined up to go and the altimeter setting drops 1 mb, am I covered? My company uses a 2 mb tolerance for reduced thrust TO, but is there a required tolerance for Max Thrust TO calcualtions?
Also I recall from Perf A that the headwind is factored by 50% and the tailwind by 150%. So what does this really mean. (ie what if I have 10 knots vs 0 knots?)
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So a reported 10kt headwind is calculated as if the real headwind were 5kts, and a reported 10kt tailwind calculated as if the real tailwind were 15kts.
If the reported headwind is 10kts, and the real value drops below 5kts (such as to 0), your calculations lose all margin of conservatism wrt wind and you eat into "other" margins, if any.
Also, because the margin used for wind is proportional to the wind, with a high reported wind you have a fair margin. At near-calm conditions the margin is negligible (50% of 0 being 0)
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Training must have really gone down hill. We were required to keep it tracking on runway leading (and 767 runway track) especially during rotation and establishing V2 to V2 + 10. If not we remained for training.
And, for routine failures (high gross weight, V1 .. the normal sort of sim thing) such is a walk in the park and just about any pilot can produce the required goods.
However,
(a) going back to some Australian DCA studies with a major domestic carrier many years ago in the sim ... for an unexpected failure, the reality was that a significant minority of pilots performed far worse with respect to tracking integrity than when they were primed for the failure .. and this for "easy" failure conditions
(b) some years ago I did a stint of contract work in the 732 sim for an operator which routinely flew (and trained for) high overspeed schedules. However, this operator also had at least one airport from which it routinely flew a short range positioning flight .. at min weight and min speed schedule .. but with no exposure in the sim.
I thought it might be interesting to see how folk fared with some increased difficulty (all in an appropriate, relaxed and friendly manner). The results I found very interesting. Even the more experienced checkies etc., had some difficulty until they'd had a couple of goes to get the gyrations under control.
As a note, this operator had modelled a large bird takeoff engine impact from the FDR and the sim responses appeared to be quite realistic to me .. sitting in the backseat, as I was, watching on ...
As we were doing a lot of initial command training (generally from 744 FO) I decided to spend some of the spare time in getting these guys and gals up to a higher than routine standard. In general, it took a very solid session (with absolute max use of freeze and reset) to move progressively back from the failure comfort zone and get to the stage where a min speed, min schedule, aft CG, worst failure (available on the box) situation (with the failure occuring during the early part of the rotation flare) could be handled with skill, dexterity and considerable aplomb .. including tracking out on the opposite end localiser .. indeed the folk could handle the situation without going to FSD during the failure .. which is pretty good in my view.
All good fun, lots of sweating in the front .. and the kids went home on a cloud of swelled head and confidence .. and slept that night like babies.
Might I be so impertinent as to suggest that you might ask to look at that sort of scenario in your next sim. Unless the sim setup is very benign in that corner of the envelope .. it is interesting.
Some examples? Any in the U.S. Airports where 737 type aircraft operate?
Can't speak to the US.
Several come to mind in Australia (CBR, HBA, for instance). Doesn't really matter .. just one is enough to defeat the philosophy you are espousing as a Standards consideration.
If I am lined up to go and the altimeter setting drops 1 mb, am I covered? My company uses a 2 mb tolerance for reduced thrust TO, but is there a required tolerance for Max Thrust TO calcualtions?
Generally we incorporate some calculation fat for pressure variations otherwise the Regulators might look at us over thick-rimmed school ma'am glasses during the audit ...
In practical terms, the effect for small Hp variations is pretty small. If you don't have any specific guidance then, presuming you do have some general chart information, say WAT limits, you can figure a notional reduce rate in terms of kg/100ft, say, and apply that for mum and the kids when looking up the RTOW data. The result will be pretty close to the sort of figure you might get by running the calculations with a minor difference in Hp input.
So a reported 10kt headwind is calculated as if the real headwind were 5kts, and a reported 10kt tailwind calculated as if the real tailwind were 15kts.
As a sideline note, if you have graphical data available, you can see this effect on the wind grid (if tabular, you might have to plot the graph yourself) in that the slope of the lines (as W/C varies) changes at zero wind .. the effect is small for light weights/distances but quite noticeable at the other end of the envelope.
And, for routine failures (high gross weight, V1 .. the normal sort of sim thing) such is a walk in the park and just about any pilot can produce the required goods.
However,
(a) going back to some Australian DCA studies with a major domestic carrier many years ago in the sim ... for an unexpected failure, the reality was that a significant minority of pilots performed far worse with respect to tracking integrity than when they were primed for the failure .. and this for "easy" failure conditions
(b) some years ago I did a stint of contract work in the 732 sim for an operator which routinely flew (and trained for) high overspeed schedules. However, this operator also had at least one airport from which it routinely flew a short range positioning flight .. at min weight and min speed schedule .. but with no exposure in the sim.
I thought it might be interesting to see how folk fared with some increased difficulty (all in an appropriate, relaxed and friendly manner). The results I found very interesting. Even the more experienced checkies etc., had some difficulty until they'd had a couple of goes to get the gyrations under control.
As a note, this operator had modelled a large bird takeoff engine impact from the FDR and the sim responses appeared to be quite realistic to me .. sitting in the backseat, as I was, watching on ...
As we were doing a lot of initial command training (generally from 744 FO) I decided to spend some of the spare time in getting these guys and gals up to a higher than routine standard. In general, it took a very solid session (with absolute max use of freeze and reset) to move progressively back from the failure comfort zone and get to the stage where a min speed, min schedule, aft CG, worst failure (available on the box) situation (with the failure occuring during the early part of the rotation flare) could be handled with skill, dexterity and considerable aplomb .. including tracking out on the opposite end localiser .. indeed the folk could handle the situation without going to FSD during the failure .. which is pretty good in my view.
All good fun, lots of sweating in the front .. and the kids went home on a cloud of swelled head and confidence .. and slept that night like babies.
Might I be so impertinent as to suggest that you might ask to look at that sort of scenario in your next sim. Unless the sim setup is very benign in that corner of the envelope .. it is interesting.
Some examples? Any in the U.S. Airports where 737 type aircraft operate?
Can't speak to the US.
Several come to mind in Australia (CBR, HBA, for instance). Doesn't really matter .. just one is enough to defeat the philosophy you are espousing as a Standards consideration.
If I am lined up to go and the altimeter setting drops 1 mb, am I covered? My company uses a 2 mb tolerance for reduced thrust TO, but is there a required tolerance for Max Thrust TO calcualtions?
Generally we incorporate some calculation fat for pressure variations otherwise the Regulators might look at us over thick-rimmed school ma'am glasses during the audit ...
In practical terms, the effect for small Hp variations is pretty small. If you don't have any specific guidance then, presuming you do have some general chart information, say WAT limits, you can figure a notional reduce rate in terms of kg/100ft, say, and apply that for mum and the kids when looking up the RTOW data. The result will be pretty close to the sort of figure you might get by running the calculations with a minor difference in Hp input.
So a reported 10kt headwind is calculated as if the real headwind were 5kts, and a reported 10kt tailwind calculated as if the real tailwind were 15kts.
As a sideline note, if you have graphical data available, you can see this effect on the wind grid (if tabular, you might have to plot the graph yourself) in that the slope of the lines (as W/C varies) changes at zero wind .. the effect is small for light weights/distances but quite noticeable at the other end of the envelope.
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Mad Scientist,
I know what the formula numbers are, my question is - is there really no factor at all if you are using no wind? Yes the math says there isn't, but practically it doesn't really make sense that if you then have a 1 knot tailwind you are no longer covered.
I have never seen a heavy stop to check the TO data when the QNH drops 1 mb. Is there really no factor in a max RTOW?
I know what the formula numbers are, my question is - is there really no factor at all if you are using no wind? Yes the math says there isn't, but practically it doesn't really make sense that if you then have a 1 knot tailwind you are no longer covered.
I have never seen a heavy stop to check the TO data when the QNH drops 1 mb. Is there really no factor in a max RTOW?
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is there really no factor at all if you are using no wind? ... it doesn't really make sense
One needs to consider what the reason is for the factor .. and that is the variability of wind (component). No guarantees along the way that all will be on the side of the pilot .. just reasonable processes and a bit of statistics. If you need/want to have a bit more fat .. then reduce the quoted headwind a bit (or increase the tailwind).
I have never seen a heavy stop to check the TO data when the QNH drops 1 mb. Is there really no factor in a max RTOW?
No factor, per se, but sensible operators will include a process to give an acceptable level of fat to cover reasonable variations. The effect for a couple of mb is pretty insignificant .. and will be within scatter for the calculated gross weight calculations against which you propose to compare the RTOW data. One needs to keep in mind that the starting point for weight calculations (the empy weight) can be a tad off the mark if you are looking to talk in terms of a few kilos ... lots of traps for young players when it comes to weighing aircraft.
One needs to consider what the reason is for the factor .. and that is the variability of wind (component). No guarantees along the way that all will be on the side of the pilot .. just reasonable processes and a bit of statistics. If you need/want to have a bit more fat .. then reduce the quoted headwind a bit (or increase the tailwind).
I have never seen a heavy stop to check the TO data when the QNH drops 1 mb. Is there really no factor in a max RTOW?
No factor, per se, but sensible operators will include a process to give an acceptable level of fat to cover reasonable variations. The effect for a couple of mb is pretty insignificant .. and will be within scatter for the calculated gross weight calculations against which you propose to compare the RTOW data. One needs to keep in mind that the starting point for weight calculations (the empy weight) can be a tad off the mark if you are looking to talk in terms of a few kilos ... lots of traps for young players when it comes to weighing aircraft.
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There is indeed absolutely no pad on the wind if you have reported zero wind; even 1 kt of wind eats into your margins.
But, and this is perhaps what you were asking for, that 1kt of wind does not doom you to the afterlife; it merely eats into the OTHER margins that exist, for things like the assumed level of aircraft performance, or thrust, or braking effectiveness, or ... With a notionally calm wind, it is unlikely that the wind will be grossly in error from that "calm" assumption. So the chances are, unless you are having a really bad day, some other element of conservatism will be there to cover for the wind effect.
But, and this is perhaps what you were asking for, that 1kt of wind does not doom you to the afterlife; it merely eats into the OTHER margins that exist, for things like the assumed level of aircraft performance, or thrust, or braking effectiveness, or ... With a notionally calm wind, it is unlikely that the wind will be grossly in error from that "calm" assumption. So the chances are, unless you are having a really bad day, some other element of conservatism will be there to cover for the wind effect.
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.. in a nutshell .. there are NO guarantees .. it is all probabalistic.
History suggests that the rules are reasonably OK as we don't have aircraft falling out of the sky day in day out.
What we would like to think we are pushing here is the VERY real need for the pilot to use his perfectly good Mk1 brain (tempered by a bunch of real world experience) when applying the rules as published in SOP type requirements.
The real danger is when the operation becomes blinkered monkey see - monkey do. If you see a reasonable need to insert a bit of conservatism then you should be prepared to do so .. and then argue the toss with the Chief Pilot a day or two later. While we all know of the horror stories associated with "difficult" companies and Chief Pilots .. in the main, most end up being fairly reasonable if the pilot's reasoning is logical and arguable.
History suggests that the rules are reasonably OK as we don't have aircraft falling out of the sky day in day out.
What we would like to think we are pushing here is the VERY real need for the pilot to use his perfectly good Mk1 brain (tempered by a bunch of real world experience) when applying the rules as published in SOP type requirements.
The real danger is when the operation becomes blinkered monkey see - monkey do. If you see a reasonable need to insert a bit of conservatism then you should be prepared to do so .. and then argue the toss with the Chief Pilot a day or two later. While we all know of the horror stories associated with "difficult" companies and Chief Pilots .. in the main, most end up being fairly reasonable if the pilot's reasoning is logical and arguable.
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j_t:
Thus far you are spoken in generalities, other than to express concern that my splay from the DER to some reasonable RNP linear area would not assure containment because of "rusty pilot" performance.
Specific question: Using FAA's AC 120-91 as a reference, specifically the straight out area method, do you believe your typical "rusty pilot" would not be able to maintain containment from the DER to say 1 mile beyond? ...2 miles? ...or more?
And, what about locations that require a 15-degree banked turn be commenced at as low as 100 feet, afe. (I know of a couple of those in California). Do you feel that a fair percentage of "rusty pilots" would miss the turn requirement or, alternatively, perhaps drop the wing into the dirt?
Is your conclusion that airplanes aren't falling out of the sky is perhaps because engines simply have not failed above V1 (while still on the runway or just after rotation) at critical locations? If so, there is likely no experience in the real world with my example of the turn being mandatory at 100 feet, agl, just after the engine fails.
I thought it might be interesting to see how folk fared with some increased difficulty (all in an appropriate, relaxed and friendly manner). The results I found very interesting. Even the more experienced checkies etc., had some difficulty until they'd had a couple of goes to get the gyrations under control.
Specific question: Using FAA's AC 120-91 as a reference, specifically the straight out area method, do you believe your typical "rusty pilot" would not be able to maintain containment from the DER to say 1 mile beyond? ...2 miles? ...or more?
And, what about locations that require a 15-degree banked turn be commenced at as low as 100 feet, afe. (I know of a couple of those in California). Do you feel that a fair percentage of "rusty pilots" would miss the turn requirement or, alternatively, perhaps drop the wing into the dirt?
Is your conclusion that airplanes aren't falling out of the sky is perhaps because engines simply have not failed above V1 (while still on the runway or just after rotation) at critical locations? If so, there is likely no experience in the real world with my example of the turn being mandatory at 100 feet, agl, just after the engine fails.
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mutt:
I presume you are speaking to me.
I don't sell anything other than my flight operations and instrument procedures expertise. I don't design instrument procedures, either; way too much liability. Only Boeing and G.E. have deep enough pockets to do that.
I also don't deal in snake oil, unlike some performance engineering departments I have dealt with.
(present company excepted, of course.)
I also find it incredulous that performance engineering is mostly still in the 1970s as to OEI flight path navigation. VOR systems, as one example, cannot deliver the accuracy presumed by some (many? most?) performance engineering departments. RNAV, and especially RNP, can deliver the goods, so to speak. No marketing concepts there.
OK enlighten us, what product are you trying to sell?
I don't sell anything other than my flight operations and instrument procedures expertise. I don't design instrument procedures, either; way too much liability. Only Boeing and G.E. have deep enough pockets to do that.
I also don't deal in snake oil, unlike some performance engineering departments I have dealt with.
(present company excepted, of course.)I also find it incredulous that performance engineering is mostly still in the 1970s as to OEI flight path navigation. VOR systems, as one example, cannot deliver the accuracy presumed by some (many? most?) performance engineering departments. RNAV, and especially RNP, can deliver the goods, so to speak. No marketing concepts there.
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aterpster
First, you have now been identified to me from other PPRuNe sources so I am familiar with your ID and basic background. There is no question here that you are other than very competent in this field so the discussion proceeds on that basis ...
Thus far you are spoken in generalities
Indeed, for other than specific runways the only specifics we can cite are regulatory
would not assure containment because of "rusty pilot" performance
Not quite what I am suggesting.
First, I have no problem with any protected area specification provided that it matches reasonably
(a) the aircraft's equipment capabilities to track within it
(b) the pilot's manipulative capability to do likewise. In this latter matter I have cited only a concern with critical failure cases (and I don't consider the usual proficiency tests as being in any way representative of critical). Personally, my concern is the low weight failure workload. However, the more general problem identified in the old DCA studies still remains valid and, considering the general reduction in manipulative skills in the modern airline world possibly is more a concern these days than in the past ?
Second, my references to concerns about pilot manipulation history is based on competent, current flightcrews - not at all rusty in the general sense.
Using FAA's AC 120-91 as a reference
The answer comes back to the above caveats.
Provided that the recommendations in the AC are observed, I would be confident that a reasonably skilled pilot should be able to address the routine nav tracking requirements. However, my observations in the sim (and the earlier DCA sim studies) indicate that one cannot be as confident for close in OEI situations other than for benign (rather than handling critical) failures.
what about locations that require a 15-degree banked turn be commenced at as low as 100 feet .. would miss the turn requirement or, alternatively, perhaps drop the wing into the dirt?
Not relevant to my concerns and I am not overly concerned about a simple turn situation either AEO or OEI after the failure has been contained. Indeed, my experience is that the averagely competent pilot can readily handle a simple turn with the failure thrown in on top of the navigation workload .. but with the criticality caveat.
is perhaps because engines simply have not failed above V1 (while still on the runway or just after rotation) at critical locations?
While we acknowledge the increased reliability of modern engines, the Standards philosophy still addresses the V1 (or later) OEI situation for the continued takeoff. Therefore, the concern relating to navigation and manipulative reliability remains a concern to be addressed.
I also find it incredulous that performance engineering is mostly still in the 1970s as to OEI flight path navigation.
Putting to one side any constraints which might be imposed by Regulatory pressure, I don't think that either Mutt or I have any problem with reduced protected areas predicated on modern RNAV capabilities.
Indeed, this is getting to be an interesting discussion ..
First, you have now been identified to me from other PPRuNe sources so I am familiar with your ID and basic background. There is no question here that you are other than very competent in this field so the discussion proceeds on that basis ...
Thus far you are spoken in generalities
Indeed, for other than specific runways the only specifics we can cite are regulatory
would not assure containment because of "rusty pilot" performance
Not quite what I am suggesting.
First, I have no problem with any protected area specification provided that it matches reasonably
(a) the aircraft's equipment capabilities to track within it
(b) the pilot's manipulative capability to do likewise. In this latter matter I have cited only a concern with critical failure cases (and I don't consider the usual proficiency tests as being in any way representative of critical). Personally, my concern is the low weight failure workload. However, the more general problem identified in the old DCA studies still remains valid and, considering the general reduction in manipulative skills in the modern airline world possibly is more a concern these days than in the past ?
Second, my references to concerns about pilot manipulation history is based on competent, current flightcrews - not at all rusty in the general sense.
Using FAA's AC 120-91 as a reference
The answer comes back to the above caveats.
Provided that the recommendations in the AC are observed, I would be confident that a reasonably skilled pilot should be able to address the routine nav tracking requirements. However, my observations in the sim (and the earlier DCA sim studies) indicate that one cannot be as confident for close in OEI situations other than for benign (rather than handling critical) failures.
what about locations that require a 15-degree banked turn be commenced at as low as 100 feet .. would miss the turn requirement or, alternatively, perhaps drop the wing into the dirt?
Not relevant to my concerns and I am not overly concerned about a simple turn situation either AEO or OEI after the failure has been contained. Indeed, my experience is that the averagely competent pilot can readily handle a simple turn with the failure thrown in on top of the navigation workload .. but with the criticality caveat.
is perhaps because engines simply have not failed above V1 (while still on the runway or just after rotation) at critical locations?
While we acknowledge the increased reliability of modern engines, the Standards philosophy still addresses the V1 (or later) OEI situation for the continued takeoff. Therefore, the concern relating to navigation and manipulative reliability remains a concern to be addressed.
I also find it incredulous that performance engineering is mostly still in the 1970s as to OEI flight path navigation.
Putting to one side any constraints which might be imposed by Regulatory pressure, I don't think that either Mutt or I have any problem with reduced protected areas predicated on modern RNAV capabilities.
Indeed, this is getting to be an interesting discussion ..
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Hi JT,
Our A319/20s have recently had their Engine Out Strategy changed at Naples RW24. Initially it was very restrictive due obstacles straight ahead on departure, the new OEI strategy is to make an early turn to avoid them and to fly through the "saddle".
The sophisticated RNAV OEI routing is in the secondary flight plan, but this can't be engaged unless the PNF made several key strokes into the FMGC just as the work load peaked. However the "Yellow Track Line" of the OEI is displayed on the MAP which can be followed simply by using the Heading Selection initially.
So it's still down to crew's prioritisation of the tasks and intelligent use of the equipment.
I don't think that either Mutt or I have any problem with reduced protected areas predicated on modern RNAV capabilities.
The sophisticated RNAV OEI routing is in the secondary flight plan, but this can't be engaged unless the PNF made several key strokes into the FMGC just as the work load peaked. However the "Yellow Track Line" of the OEI is displayed on the MAP which can be followed simply by using the Heading Selection initially.
So it's still down to crew's prioritisation of the tasks and intelligent use of the equipment.
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j_t:
Any reduction would not occur at the DER, rather starting a mile or two beyond the DER. But, that reduction would see the linear containment areas being navigated with performance based navigation instead of a heading or some marginal (at best) VOR radial or NDB bearing.
I can't speak to regulatory requirements elsewhere, but such a modern concept would have no issues with FAA regulations. To the contrary, the path for approval already exists. From what I know, many "first world" nations would have no quarrel using PNB for the OEI flight path. And, some two years ago, Naverus provided just such an OEI flight path for China to use at Lhasa. The Airbus A319 was recently added to that approval:
Naverus | Performance Based Navigation & Required Navigation Performance
Also from their web site:
RNP AR procedures designed to Naverus’ criteria include:
Putting to one side any constraints which might be imposed by Regulatory pressure, I don't think that either Mutt or I have any problem with reduced protected areas predicated on modern RNAV capabilities.
I can't speak to regulatory requirements elsewhere, but such a modern concept would have no issues with FAA regulations. To the contrary, the path for approval already exists. From what I know, many "first world" nations would have no quarrel using PNB for the OEI flight path. And, some two years ago, Naverus provided just such an OEI flight path for China to use at Lhasa. The Airbus A319 was recently added to that approval:
Naverus | Performance Based Navigation & Required Navigation Performance
Also from their web site:
RNP AR procedures designed to Naverus’ criteria include:
- Instrument approach procedures including missed approaches
- Departure procedures
- Non-normal (engine inoperative) departure procedures
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the new OEI strategy is to make an early turn to avoid them and to fly through the "saddle".
Generally there are multiple ways to fix the departure problem .. the aim being to end up with a compromise between sensible flight standards and making a dollar by optimising the payload.
this can't be engaged unless the PNF made several key strokes into the FMGC just as the work load peaked.
Crew workload, naturally enough, is part of the flight standards consideration. In my view the desirable option for a difficult runway is to make the AEO and OEI flight paths the same so that the workload is reduced ...
So it's still down to crew's prioritisation of the tasks and intelligent use of the equipment.
That's an operator cop out for something as important as escape procedures. In my view the operator should be prescribing the way the crew is to address the problem. It is quite unreasonable (and leads, potentially, to a significant standardisation problem) to load the crew up with decisions that are not properly in their basket. The crew should be flying it, not planning the escape.
rather starting a mile or two beyond the DER
.. where the 300 ft is overtaken by the expanding splay ..
Non-normal (engine inoperative) departure procedures
This remains the sticking point for me as the question of pilot skill level remains unanswered for the more critical failure cases. The problems associated with the evident skill reduction across the Industry is a bit of a worry if we are going to have the hard bits come in a bit closer to the notional escape path ? .. albeit that the close in areas remain unchanged. In respect to the latter, I think that the sim history suggests some concern anyway.
Generally there are multiple ways to fix the departure problem .. the aim being to end up with a compromise between sensible flight standards and making a dollar by optimising the payload.
this can't be engaged unless the PNF made several key strokes into the FMGC just as the work load peaked.
Crew workload, naturally enough, is part of the flight standards consideration. In my view the desirable option for a difficult runway is to make the AEO and OEI flight paths the same so that the workload is reduced ...
So it's still down to crew's prioritisation of the tasks and intelligent use of the equipment.
That's an operator cop out for something as important as escape procedures. In my view the operator should be prescribing the way the crew is to address the problem. It is quite unreasonable (and leads, potentially, to a significant standardisation problem) to load the crew up with decisions that are not properly in their basket. The crew should be flying it, not planning the escape.
rather starting a mile or two beyond the DER
.. where the 300 ft is overtaken by the expanding splay ..
Non-normal (engine inoperative) departure procedures
This remains the sticking point for me as the question of pilot skill level remains unanswered for the more critical failure cases. The problems associated with the evident skill reduction across the Industry is a bit of a worry if we are going to have the hard bits come in a bit closer to the notional escape path ? .. albeit that the close in areas remain unchanged. In respect to the latter, I think that the sim history suggests some concern anyway.
