Flight International and Future A350 pilots `learn by doing`
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Originally Posted by Clandestino
Now you mention it; both Habsheim and Hudson have one more common trait besides both involving A320: both aeroplanes hit the deck in alpha prot with significant aft stick displacement. If flight controls were classical or brand B FBW with overridable limits, outcome would be much worse.
Now sit and watch the outburst of usual tales how investigating bodies hate the pilots and protect the evil Airbus.
N/A and not necessary to the NTSB on the Hudson though.
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Originally Posted by Dozy
publishing bulletins to airlines notifying them of recent UAS issues and of the importance of UAS procedures
publishing bulletins to airlines notifying them of recent UAS issues and of the importance of UAS procedures
FAA
We are issuing this AD to prevent ice from forming on air data system sensors and consequent loss of or misleading airspeed indication on all airspeed indicating systems, which could lead to loss of control of the airplane.”
Boeing
Boeing stated that loss of, or erroneous, airspeed indications do not necessarily lead to loss of control because other indications can be used to safely fly the airplane. Boeing noted that multiple in-service events have occurred without loss of control when the flight crew followed the procedures that mitigate loss of air data.
FAA
We disagree /…/ Although some in-service events might have occurred without loss of control, loss of, or misleading airspeed indication on all airspeed indicating systems can, in fact, lead to an unsafe condition of loss of airplane control. FAA Advisory Circular (AC) 25-11A, dated June 21, 2007 typically classifies loss of all airspeed displays (including the standby display) as a ''catastrophic'' failure condition.
Last edited by jcjeant; 24th Feb 2013 at 14:41.
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This is normally addressed by obsessively proceduralising everything so that as few as possible 'judgement calls' are required from the pilot.
Where there isn't automation there are procedures - the less room for 'crew creativity' the better as far as safety designers are concerned.
You can not foresee all eventualities and write procedures for everything. Things unusual will happen. Go back a read what I reported was the NTSB statement after the aerobatic China airlines B747. OK, the other side of the coin is that if the crew had followed airmanship procedures diligently they should not have arrived in the poo; but they did and they survived. It was a classic case of a demo about the definition of an ace pilot. The skills should have been used to avoid the scenario rather tan being used to escape from it.
I spent a good few years with cadet F/O's who could handle the a/c OK, but did not know what to think about in an unusual scenario. Their first act was not to act with airmanship, but to try and remember what was written in the SOP book. While that thinking was going on the a/c was still travelling very fast and sometimes not doing what you wanted. There wasa delay in action. Then there was the realisation that there was nothing in the book, or that what was described did not quite fit the scenario. Now they were lost. What to do? Should I deviate from the nearest SOP. They were afraid to. Dilly & dally while the situation became worse. That's one of the major problems with SOP gurus being accelerated into command.
Where there isn't automation there are procedures - the less room for 'crew creativity' the better as far as safety designers are concerned.
You can not foresee all eventualities and write procedures for everything. Things unusual will happen. Go back a read what I reported was the NTSB statement after the aerobatic China airlines B747. OK, the other side of the coin is that if the crew had followed airmanship procedures diligently they should not have arrived in the poo; but they did and they survived. It was a classic case of a demo about the definition of an ace pilot. The skills should have been used to avoid the scenario rather tan being used to escape from it.
I spent a good few years with cadet F/O's who could handle the a/c OK, but did not know what to think about in an unusual scenario. Their first act was not to act with airmanship, but to try and remember what was written in the SOP book. While that thinking was going on the a/c was still travelling very fast and sometimes not doing what you wanted. There wasa delay in action. Then there was the realisation that there was nothing in the book, or that what was described did not quite fit the scenario. Now they were lost. What to do? Should I deviate from the nearest SOP. They were afraid to. Dilly & dally while the situation became worse. That's one of the major problems with SOP gurus being accelerated into command.
Originally Posted by CONF iture
How an Airline could be aware of a recurrent issue if the information stays in the Manufacturer headquarters ?
. . . .
What did Airbus ?
. . . .
What did Airbus ?
Essentially, communications regarding ADR/airspeed problems began in 1996. Information to airlines about Pitot/ADR/Airspeed problems was widely available in varying formats.
As mentioned previously, it is up to individual airlines to use manufacturer's information to best advantage in terms of training, standards and checking.
Originally Posted by RAT_5
That's one of the major problems with SOP gurus being accelerated into command.
The predisposition towards the present "SOP / Automation tight coupling" is a response to cover off a chronic lack of actual flying experience and/or the ability to think in an airplane.
Airmanship cannot be taught; it requires time in and more than a few shots of adrenaline before it sinks in that flying does not consist of running a software platform at a desk but can instead kill one and everyone else on board, (in AF447's case in less time than it takes to wait in line for a Starbucks coffee).
Last edited by PJ2; 24th Feb 2013 at 16:23.
Originally Posted by CONFiture
Sorry, just no feeling here, just damage control.
Originally Posted by PJ2
The predisposition towards the present "SOP / Automation tight coupling" is a response to cover off a chronic lack of actual flying experience and/or the ability to think in an airplane.
Anyway, while I recognize there is problem with pilots' manual and mental skills, and something ought to be done about it, it is not as bad as some doomsayers around here suggest, basing their dire warnings on nothing but a few high-profile accidents.
Originally Posted by PJ2
Airmanship cannot be taught; it requires time in and more than a few shots of adrenaline before it sinks in that flying does not consist of running a software platform at a desk but can instead kill one and everyone else on board, (in AF447's case in less time than it takes to wait in line for a Starbucks coffee).
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Originally Posted by Clandestino
There is such thing as excessive pitch at ditching
there's no such thing as the magical area of spectacular climb performance below Vx
Now if you think Airbus has it all wrong with the 'climb perf below Vx' give them a call because that's really what they want us to do to save us from the ground.
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Their first act was not to act with airmanship, but to try and remember what
was written in the SOP book.
was written in the SOP book.
to fall back on. Back when I joined a major with only 1700hrs in Chieftains and other various
twins, I'd already learnt what was going to kill me and what isn't......with a good measure of
lateral thinking practice. And I had good ab-initio training with a serious old fart who instilled
airmanship from the very beginning.
No one can blame these cadets for being unable to gain GA experience but, and this is what
I find objectionable - they are thrown into the RHS (ie SIC) with bugger-all under their belts
and minimal to non-existent airmanship instilling. At SQ yonks ago, anyone who joined with
less than 1000 hrs was slam-dunked to being the captain's sexual advisor for no less than 2
yrs and after that was checked to COMMAND status, then given the RHS. I am no fan of SIA
but back then they had their heads screwed on right.
...Since the advent of these lousy low-cost low-class outfits we've seen the degradation of
good quality training of cadets. Indeed it has permeated through to many premium airlines
who've realised there are bucks to be made by putting a kid where a pilot should be and in
doing so put the onus on line Captains to a maintain safe operation under the worn cliche
of "use CRM". CRM is useless with a kid who a) hasn't been competently trained, and b) has
no interest in furthering any pilotage or thinking skills except that of the bare minimum.
I've just done a sim all-nighter with 10 cadets so I admit I'm bloody tired right now, but out
of the lot only 3 are very keen to learn this "airmanship thing". The rest couldn't give a crap
and just want to get through with the bare minimum. I can see these 3 one day becoming
good commanders - out of the remaining 7 only 4 will be passable by our standards, and the
remaining 3 I won't dare put my wife and kid on board if they ever make it to the LHS - but
of course they eventually will.
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Originally Posted by PJ2
You may not be aware that Airbus publishes a number of communications, (FAST, Status of the Fleet reviews, etc), discussing issues with their aircraft
Where is the expected reflection following Air Caraibes events ?
Originally Posted by Air Caraibes memo - P13
In addition, Airbus engineers have understood all the difficulty encountered by the crew for a rapid and effective implementation of the UNRELIABLE SPEED INDICATION procedure.
They agreed to the admissibility of our remarks and reflect therefore on a modification for the checklists.
They agreed to the admissibility of our remarks and reflect therefore on a modification for the checklists.
A pro-active attitude was necessary, and still is.
Originally Posted by CONFiture
Sorry, just no feeling here, just damage control.
N/A and not necessary to the NTSB on the Hudson though.
N/A and not necessary to the NTSB on the Hudson though.
Originally Posted by CONFiture
Forget about any excess as the Airbus recommended pitch for ditching was already refused to Sully, consequence of an obscure alpha limitation, well short of alpha max.
Originally Posted by NTSB AAR/10/03, pages 97-98
The A320 alpha-protection mode incorporates features that can attenuate pilot sidestick pitch inputs. Because of these features, the airplane could not reach the maximum AOA attainable in pitch normal law for the airplane weight and configuration; however, the airplane did provide maximum performance for the weight and configuration at that time.
Originally Posted by NTSB AAR/10/03, page 98
The NTSB recommends that the FAA require Airbus operators to expand the AOA-protection envelope limitations ground-school training to inform pilots about alpha-protection mode features while in normal law that can affect the pitch response of the airplane.
Originally Posted by CONFiture
No need for magical or spectacular, just that little something to not catch too much of the trees to keep flying. But wait a minute, that's exactly what alpha max can provide when both engines are pushing as hard as the report states they were ...
Originally Posted by CONFiture
Now if you think Airbus has it all wrong with the 'climb perf below Vx' give them a call because that's really what they want us to do to save us from the ground.
Slasher, spot on
I'm afraid what was meant to be benevolent advice will come to haunt us as a dire warning:
Originally Posted by David Petit Davies
The demand of jet transport flying can be best met by enthusiasm. Personal enthusiasm for the job is beyond value because it is a built-in productive force and those who have it do not have to be pushed into practice and the search for knowledge. Enthusiasm thus generates its own protection. This is the frame of mind which needs to be developed for the best execution of the airline's pilot task.
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I spent a good few years with cadet F/O's who could handle the a/c OK, but did not know what to think about in an unusual scenario. Their first act was not to act with airmanship, but to try and remember what was written in the SOP book. While that thinking was going on the a/c was still travelling very fast and sometimes not doing what you wanted. There wasa delay in action. Then there was the realisation that there was nothing in the book, or that what was described did not quite fit the scenario. Now they were lost. What to do? Should I deviate from the nearest SOP. They were afraid to. Dilly & dally while the situation became worse. That's one of the major problems with SOP gurus being accelerated into command
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That's one of the major problems with SOP gurus being accelerated into command
.... and they are the most pretentious contributors on this forum
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Originally Posted by Clandestino
Some operators do include info about aeroplane's behaviour in alpha protection mode and give their crews hands-on sim training in it, some just don't, wishfully hoping the dry information contained in FCOM will be absorbed by the crews.
As designed, the airplane did provide maximum performance for the weight and configuration at that time, but prevented the pilot from taking advantage of his experience to optimize the flare for the best possible touchdown.
But please give me the debrief on alpha, speed, flighpath and RoD numbers in report that I see where I'm way out. You may add the attitude as well ...
Even if we accept there was secret organization that tampered with FDRs, there is still that all too infamous video which pretty vividly shows just what was the energy state of the aeroplane before she made controlled flight into trees.
I'd estimate number of sleepless night at Toulouse caused by PPRuNe critics to be between 0 and 0.001.
I have no problem with Airbus procedures or manuals as they are, knowing very well how "perfect" often is an enemy of "good enough". As the aerospace landscape changes, they will be changed but by no means in a way to satisfy someone whose notions about flying in general and Airbus in particular can't be put in coherent shape useful for anything more than shouting from internet soapbox.
PPRuNe is anonymous forum where anyone interested in flying can freely exchange ideas, opinions, experiences, advices, etc. Price we have to pay for this is necessity to endure the occasional outbursts of opinionated nonsense from attention seekers. I'd say it's well worth paying.
PPRuNe is anonymous forum where anyone interested in flying can freely exchange ideas, opinions, experiences, advices, etc. Price we have to pay for this is necessity to endure the occasional outbursts of opinionated nonsense from attention seekers. I'd say it's well worth paying.
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Originally Posted by Clandestino
As the aerospace landscape changes, they will be changed but by no means in a way to satisfy someone whose notions about flying in general and Airbus in particular can't be put in coherent shape useful for anything more than shouting from internet soapbox.
Originally Posted by Clandestino
Price we have to pay for this is necessity to endure the occasional outbursts of opinionated nonsense from attention seekers.
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The pilot-related contributing factors to the incident you're referring to were never about being able to clear the trees, they were about poor decision-making prior to and during the approach. Put bluntly, even if the incident had been non-fatal, the Captain would still have been held responsible for these factors with a similarly negative impact on his career.
Last edited by DozyWannabe; 1st Mar 2013 at 17:35.
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UAV technology has arrived.
Pilot(s) are not (operationally) required, at any level, any more.
Pilot(s) are not (operationally) required, at any level, any more.
Huh? Problem is that too many UAVs have NOT returned to base. The exact number of "missing" UAVs remains classified, probably so as not to spook the taxpayers.
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Originally Posted by DOZY
To the best of my knowledge you've been banging on this point for about two years now and you're still the only one who's making it. Perhaps someone can find an aero engineer to run the numbers to get a definitive answer (such material would be perfect for a new thread in AH&N or Tech Log), but forgive me if I remain sceptical until such material becomes available.
The captain progressively pulled aft on the sidestick as the airplane descended below 100 feet, and he pulled the sidestick to its aft stop in the last 50 feet, indicating that he was attempting to raise the airplane nose to flare and soften the touchdown on the water.
Now if you think you need an aero engineer to validate the point just go for it.
Originally Posted by DOZY
The pilot-related contributing factors to the incident you're referring to were never about being able to clear the trees, they were about poor decision-making prior to and during the approach. Put bluntly, even if the incident had been non-fatal, the Captain would still have been held responsible for these factors with a similarly negative impact on his career.
Do a Hover - it avoids G
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On the other hand some might say the touchdown attitude achieved was just right and avoided a nose high touchdown that could have given a violent pitch down when the tail made contact followed by a plough under.
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Dozy,
I don’t usually dare post in Rumours and News, but since you ask ..................
So far as it goes, Confiture has to be right; he is after all just quoting from the NTSB report. Unfortunately it is a selective quotation. The full version would be:
IOW, the flare ability was restricted, but it didn’t matter a damn. If one probes a little it is easy to see why they said that.
The NTSB report states:
That defines a package of conditions, you cannot pick just one out and say that is the criterion by which the process should be judged. In particular, the AI conditions include engine power available. There is no way you are going to get – 0.5deg glide slope, or even the -1deg of the actual certification demonstration, with no thrust. That being so, why pick out 11deg pitch as being optimum for the engines out case? Why, for that matter, assume that higher AoAs translate into more favourable ditching results?
The rear fuselage loads, which affect all of these considerations, come in two parts:
Pressure loads, which we may reasonably suppose to be proportional to (speed squared) times (Pitch plus FPA = AoA) and
Inertia (impulse) loads which will be proportional to the rate of descent at splashdown.
If you run the sums (I have) it turns out that the pressure loads increase slightly if you hit the water at higher AoA, because the AoA effect outweighs the speed reduction. The rate of descent though is more or less independent of AoA at impact because the aircraft, being thoroughly on the back of the drag curve, has a much worse L/D at higher AoA and the increased glide slope angle offsets the speed reduction.
There is therefore nothing to suggest that pulling to a bigger AoA at impact would have improved the outcome.
I’m not convinced by :
For sure he could do little to reduce the vertical speed, but I’m not convinced that the ”obscure system restriction” limits the aircraft to 9.5 degrees attitude. If that were true Habsheim (where the aircraft got to 15deg AoA at 30 ft AGL) could not have happened!
I suggest that rather than restricting the actual pitch or AoA, the system actually attenuates the pilot input by changing the stick/elevator gearing. Somewhere I have either read or heard that in early flight test the aircraft was prone to PIO in the flare and that the laws were changed to eliminate this tendency. Reducing system gain would be a classic way of doing this. Such a feature would certainly have the effect of reducing the pilot’s ability to flare in a short period, but would not in fact be a hard limit on AoA.
The NTSB report also says:
Those sentences make a nonsense of any assertion that the attenuation of pilot's control input in some mysterious way condemned the aircraft to never bettering - 3.5 deg FPA in the engine out ditching case.
Perhaps someone can find an aero engineer to run the numbers to get a definitive answer.
So far as it goes, Confiture has to be right; he is after all just quoting from the NTSB report. Unfortunately it is a selective quotation. The full version would be:
The A320 alpha-protection mode incorporates features that can attenuate pilot sidestick pitch inputs. Because of these features, the airplane could not reach the maximum AOA attainable in pitch normal law for the airplane weight and configuration; however, the airplane did provide maximum performance for the weight and configuration at that time.
The NTSB report states:
The January 21, 1988, Airbus certification test report stated that the fuselage of an A320 would “undergo no destruction liable to create a water passage” if the airplane ditched with the following parameters:
landing gear retracted,
11° pitch,
-0.5° glideslope, and
flaps in landing configuration for minimum speed.
According to Airbus, the ditching certification criteria also assumed that engine power was available, that the descent rate was 3.5 feet per second (fps), and that the airplane landed longitudinal to any water swells. These criteria are consistent with the test results published in the NACA reports.
landing gear retracted,
11° pitch,
-0.5° glideslope, and
flaps in landing configuration for minimum speed.
According to Airbus, the ditching certification criteria also assumed that engine power was available, that the descent rate was 3.5 feet per second (fps), and that the airplane landed longitudinal to any water swells. These criteria are consistent with the test results published in the NACA reports.
The A320 ditching tests, according to the AI submission to the NTSB,
“were performed with scale models to identify the approach scenario (in terms of slope, pitch and speed) which gave the best overall aircraft behavior during ditching; i.e.
No nose-diving or loss of aircraft control
No break-up of fuselage
Minimum lower fuselage deformation
“were performed with scale models to identify the approach scenario (in terms of slope, pitch and speed) which gave the best overall aircraft behavior during ditching; i.e.
No nose-diving or loss of aircraft control
No break-up of fuselage
Minimum lower fuselage deformation
Pressure loads, which we may reasonably suppose to be proportional to (speed squared) times (Pitch plus FPA = AoA) and
Inertia (impulse) loads which will be proportional to the rate of descent at splashdown.
If you run the sums (I have) it turns out that the pressure loads increase slightly if you hit the water at higher AoA, because the AoA effect outweighs the speed reduction. The rate of descent though is more or less independent of AoA at impact because the aircraft, being thoroughly on the back of the drag curve, has a much worse L/D at higher AoA and the increased glide slope angle offsets the speed reduction.
There is therefore nothing to suggest that pulling to a bigger AoA at impact would have improved the outcome.
I’m not convinced by :
but despite the full backstick, the protections did not allow more than 9.5 degrees and the pilots could do nothing to decrease that impressive vertical speed of 750 feet a minute.
The 11 degrees attitude was refused to the pilot even if adequate margin in the AoA before attaining alpha max was available ...
He could not pull more than 9.5 degrees attitude in the flare due to obscure system restriction.
The 11 degrees attitude was refused to the pilot even if adequate margin in the AoA before attaining alpha max was available ...
He could not pull more than 9.5 degrees attitude in the flare due to obscure system restriction.
I suggest that rather than restricting the actual pitch or AoA, the system actually attenuates the pilot input by changing the stick/elevator gearing. Somewhere I have either read or heard that in early flight test the aircraft was prone to PIO in the flare and that the laws were changed to eliminate this tendency. Reducing system gain would be a classic way of doing this. Such a feature would certainly have the effect of reducing the pilot’s ability to flare in a short period, but would not in fact be a hard limit on AoA.
The NTSB report also says:
...... a total of 14 runs were performed in the engineering simulator in which pilots attempted to touch down on the water within a target flightpath angle of -0.5°, consistent with the structural ditching certification criteria. Two of the 14 runs were discarded because of poor data. Of the remaining 12 runs, 4 were attempted using CONF 2, 4 were attempted using CONF 3, and 4 were attempted using CONF 3/Slats only.
In 11 of the 12 runs, the touchdown flightpath angle ranged between -1.5° and -3.6° (the touchdown flightpath angle achieved on the accident flight was -3.4°). In 1 of these 12 runs, a -0.2° touchdown flightpath angle was achieved by an Airbus test pilot who used a technique that involved approaching the water at a high speed, leveling the airplane a few feet above the water with the help of the radar altimeter, and then bleeding off airspeed in ground effect until the airplane settled into the water
In 11 of the 12 runs, the touchdown flightpath angle ranged between -1.5° and -3.6° (the touchdown flightpath angle achieved on the accident flight was -3.4°). In 1 of these 12 runs, a -0.2° touchdown flightpath angle was achieved by an Airbus test pilot who used a technique that involved approaching the water at a high speed, leveling the airplane a few feet above the water with the help of the radar altimeter, and then bleeding off airspeed in ground effect until the airplane settled into the water
Last edited by Owain Glyndwr; 7th Mar 2013 at 05:08.