AF 447 Thread No. 10
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Lyman,
After lurking and reading the recent posts on this thread, it's time for a reality check. From the BEA Final Report:
The chart on Pg.96 showing PF's Side Stick Pitch Position confirms this.
One more time, It wasn't the airplane that caused this...
"He tried the entire while to drop the nose, by pushing the Stick forward".
Pg.173: Following the autopilot disconnection, the PF very quickly applied nose-up side stick inputs. The PF's inputs may be classified as abrupt and excessive. The excessive amplitude of these inputs made them unsuitable and incompatible with recommended airplane handling practices for high altitude flight.
Pg.183: In the first minute after the disconnection of the autopilot, the airplane exited its flight envelope. Neither of the two crew members had the clarity of thought necessary to take the corrective actions. However, every passing second required a more purposeful corrective piloting input.
After autopilot disconnection the nose-up inputs produced a load factor of up to 1.6 g, that is to say 1.4 g if the turbulence component is excluded. Maintaining a high pitch attitude first resulted, when the airplane had sufficient speed, in a fast climb speed (up to 7,000 ft/min) and then a rapid increase in angle of attack. At high altitude, such climb speed can only be achieved by converting kinetic energy to potential energy, that is to say at the expense of rapid decrease in flight path speed.
In addition, the thrust value of 84% N1 was lower than the thrust necessary for level flight (95% N1) due to the reduced mach ordered a few seconds before autopilot disconnection, then changed to "Thrust Lock" mode at 2 h 10 min10. The thrust was readjusted towards CLIMB at 2 h 10 min 23 even though the airplane was already climbing rapidly with a vertical speed of 6,000 ft/min.
These factors induced a rapid reduction in the kinetic energy and brought the airplane above its lift ceiling, at a Mach level at which it was then flying. This rapid exit from the flight envelope was not understood and thus not anticipated by the pilots.
After autopilot disconnection the nose-up inputs produced a load factor of up to 1.6 g, that is to say 1.4 g if the turbulence component is excluded. Maintaining a high pitch attitude first resulted, when the airplane had sufficient speed, in a fast climb speed (up to 7,000 ft/min) and then a rapid increase in angle of attack. At high altitude, such climb speed can only be achieved by converting kinetic energy to potential energy, that is to say at the expense of rapid decrease in flight path speed.
In addition, the thrust value of 84% N1 was lower than the thrust necessary for level flight (95% N1) due to the reduced mach ordered a few seconds before autopilot disconnection, then changed to "Thrust Lock" mode at 2 h 10 min10. The thrust was readjusted towards CLIMB at 2 h 10 min 23 even though the airplane was already climbing rapidly with a vertical speed of 6,000 ft/min.
These factors induced a rapid reduction in the kinetic energy and brought the airplane above its lift ceiling, at a Mach level at which it was then flying. This rapid exit from the flight envelope was not understood and thus not anticipated by the pilots.
Before returning to the peanut gallery amongst this august group of heavy pilots, I shall once again challenge Cland.......
From A330 FCOM:
So the jet "appears" to be a pitch attitude command, and the turn implementation appears to also allow for the gee involved to maintain both the established pitch AND roll. We all know that 60 degrees of bank requires 2 gees, and so forth, huh?
My point is that the sucker is a one gee jet, and the autotrim will allow the pilot to relax the stick to maintain an attitude. Our pure gee command ( gear up) resulted in us being neutral WRT speed stability, so we had to use power to maintain a constant speed. Gear down we had an AoA bias to make the jet "feel" like a "normal" jet, similar to the 'bus "flare mode"
And note the phrase in FCOM "With the side stick neutral, the system maintains one gee in pitch corrected for pitch attitude" How one can assert the jet is a pitch attitude control law still bothers me. It may appear to be an "attitude control law", but it ain't. And that's why I said the actions of the THS and such could have an "insidious" effect that some may not appreciate.
Further, my understanding of aero is that a straight mechanical system that we had long ago, and in some jets to this day, you trim for AoA, not gee, not attitude, not speed. I think most of us learned in planes like that, ya think? Ask Mach or Smilin' Ed or any Navy type, and even some of we Air Force pukes. And so...
True, we normally fly to achieve an attitude and simply keep the AoA below the stall angle. Trim to reduce the stick force requirement and so forth. However, many of us were taught to trim for a speed when climbing or descending, and especially for final approach. Not necessarily an attitude. And that's AoA, which works with thrust and the induced drag to get the "speed". Then your power controls the climb angle/climb rate, or the other way.
I do not intend to conduct the pre-flight instruction for my newbie student for most here. I just want to point out the way the 'bus is designed from looking at the manuals and such some of you presented to me.
From A330 FCOM:
So the jet "appears" to be a pitch attitude command, and the turn implementation appears to also allow for the gee involved to maintain both the established pitch AND roll. We all know that 60 degrees of bank requires 2 gees, and so forth, huh?
Eh... unlike F-16 which has G-trim, Airbus is made to be flightpath stable, so it will achieve 1G in wings level horizontal flight, not by chasing 1G but rather by trying to keep the flightpath constant. If we don't go into details and try to build theories on them, "Stick free it holds 1G" is good enough approximation. Displacing the stick commands the flightpath change with so-and-so gees, proportional to displacement
And note the phrase in FCOM "With the side stick neutral, the system maintains one gee in pitch corrected for pitch attitude" How one can assert the jet is a pitch attitude control law still bothers me. It may appear to be an "attitude control law", but it ain't. And that's why I said the actions of the THS and such could have an "insidious" effect that some may not appreciate.
Further, my understanding of aero is that a straight mechanical system that we had long ago, and in some jets to this day, you trim for AoA, not gee, not attitude, not speed. I think most of us learned in planes like that, ya think? Ask Mach or Smilin' Ed or any Navy type, and even some of we Air Force pukes. And so...
Autotrim is just automatic trim. Any aeroplane, anywhere, anytime is properly flown with reference to attitude. Whether the residual stick force after the required performance is achieved is trimmed out manually or automatically is just a minor detail.
I do not intend to conduct the pre-flight instruction for my newbie student for most here. I just want to point out the way the 'bus is designed from looking at the manuals and such some of you presented to me.
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I think most of us learned in planes like that, ya think?
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Accelerations are usually measured in the body-axis system: ax along the longitudinal axis, ay perpendicular to the plane of symmetry, and az perpendicular to ax and ay.
"1 G in pitch corrected for pitch attitude" probably means 1G along the earth vertical, i.e. constant vertical speed.
"1 G in pitch corrected for pitch attitude" probably means 1G along the earth vertical, i.e. constant vertical speed.
Dozy, Power + Attitude = performance when flying.
(For a given configuration, be it clean, flaps at x degrees, gear down, whatever ....)
To trim for G or flight path, rather than for attitude, is to add complexity to that simple performance formula. There may be good design reasons for that to include passenger comfort, optimal cruise fuel consumption, or a dozen other factors.
Once the conversion course is over, who is flying, and how often? Considering recency and frequency of training and prifociency in flying: who is flying and how, when they are flying and particularly when they are hand flying?
(regarding AF 447 and a few other UAS events, without airspeed indications, you don't have a critical performance instrument, but you do have available in this case both pitch and power information, and you have both altimeter and VSI to get a sense of "level" or '1 G' flight, or something other than that).
Last of all, if like most pilots you are initially taught the above forumula, and imbed that relationship first, how many reps of a different conceptual approach do you need in order to fly "G" or "flight path" rather than pitch using your hands and feet, and internalize that? Varies with each pilot, I suspect.
I'd be interested to hear from those who do pilot training and conversion comment on the above. When pilots actually fly the Magic Bus, are the pilots flying pitch and power?
Some apparently do. (based on various inputs from actual pilots in 3+ years of this topic)
Are they wrong to do so, since the plane as designed isn't meant (under the Normal condition) to fly attitude but rather flight path? (It was painful for me to type that, but that is where this sub genre of discussion of flight modes and laws has taken me).
HazelNuts: zero vertical speed translates to "0" on the VSI when flying, right?
(For a given configuration, be it clean, flaps at x degrees, gear down, whatever ....)
To trim for G or flight path, rather than for attitude, is to add complexity to that simple performance formula. There may be good design reasons for that to include passenger comfort, optimal cruise fuel consumption, or a dozen other factors.
Once the conversion course is over, who is flying, and how often? Considering recency and frequency of training and prifociency in flying: who is flying and how, when they are flying and particularly when they are hand flying?
(regarding AF 447 and a few other UAS events, without airspeed indications, you don't have a critical performance instrument, but you do have available in this case both pitch and power information, and you have both altimeter and VSI to get a sense of "level" or '1 G' flight, or something other than that).
Last of all, if like most pilots you are initially taught the above forumula, and imbed that relationship first, how many reps of a different conceptual approach do you need in order to fly "G" or "flight path" rather than pitch using your hands and feet, and internalize that? Varies with each pilot, I suspect.
I'd be interested to hear from those who do pilot training and conversion comment on the above. When pilots actually fly the Magic Bus, are the pilots flying pitch and power?
Some apparently do. (based on various inputs from actual pilots in 3+ years of this topic)
Are they wrong to do so, since the plane as designed isn't meant (under the Normal condition) to fly attitude but rather flight path? (It was painful for me to type that, but that is where this sub genre of discussion of flight modes and laws has taken me).
HazelNuts: zero vertical speed translates to "0" on the VSI when flying, right?
Last edited by Lonewolf_50; 6th Mar 2013 at 19:17.
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To trim for G or flight path, rather than for attitude, is to add complexity to that simple performance formula.
Given that Airbus supplied pitch/power data to pilots from the get-go I think that aspect works in much the same way as it does on other types as long as you stay within the envelope. Even if there were some variation I have a strong suspicion that it would be barely noticeable.
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Flying the pitch and power given in the table will keep the airplane within the envelope. Small power adjustments may be necessary to maintain a given altitude.
Given that Airbus supplied pitch/power data to pilots from the get-go I think
That isn't as important is the issue of "you tend to play the way you practice." What is practiced?
PJ reproduced an A320 pitch and power table from the 90's. If you practice using that, or resorting to it under conditions X, Y, or Z, then when you are missing that critical performance instrument, airspeed, you call that up and proceed.
If that's how you train.
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Hi,
Lonewolf_50
Maybe not important or irrelevant for you ...
But it is very important for the lawyers of the victims families and judges who have to fix and evaluate the compensation to be paid to the parties concerned
Because it is precisely people died that compensation should be paid (in accordance with the laws in force governing such allowances)
And you should know that if in addition to die .. victims have suffered moral damage before death (fear of death .. anxiety .. etc .. ) .. the allowance must be increased
Ask any lawyer about it .. and he will tell you the importance of these details (irrelevant for you) for the assessment of compensation
Lonewolf_50
Given that they died as a result of the crash, their 'fear and anxiety' seems nearly irrelevant to me
But it is very important for the lawyers of the victims families and judges who have to fix and evaluate the compensation to be paid to the parties concerned
Because it is precisely people died that compensation should be paid (in accordance with the laws in force governing such allowances)
And you should know that if in addition to die .. victims have suffered moral damage before death (fear of death .. anxiety .. etc .. ) .. the allowance must be increased
Ask any lawyer about it .. and he will tell you the importance of these details (irrelevant for you) for the assessment of compensation
Last edited by jcjeant; 6th Mar 2013 at 20:41.
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http://www.bea.aero/docspa/2009/f-cp...nexe.06.en.pdf
I guess it depends what you mean by "practiced" - as far as I can tell the intent was to follow the procedures outlined in the above document in the event of unreliable airspeed, but as to whether or how often these procedures were drilled, I can't say.
I guess it depends what you mean by "practiced" - as far as I can tell the intent was to follow the procedures outlined in the above document in the event of unreliable airspeed, but as to whether or how often these procedures were drilled, I can't say.
I'd be interested to hear from those who do pilot training and conversion comment on the above. When pilots actually fly the Magic Bus, are the pilots flying pitch and power?
Some apparently do. (based on various inputs from actual pilots in 3+ years of this topic)
Some apparently do. (based on various inputs from actual pilots in 3+ years of this topic)
Last edited by Lonewolf_50; 6th Mar 2013 at 21:46.
Because it is precisely people died that compensation should be paid (in accordance with the laws in force governing such allowances) And you
should know that if in addition to die .. victims have suffered moral damage
before death (fear of death .. anxiety .. etc .. ) .. the allowance must be
increased
should know that if in addition to die .. victims have suffered moral damage
before death (fear of death .. anxiety .. etc .. ) .. the allowance must be
increased
Thanks.
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Some pilots here don't agree with my thinking their 11 degree pitch attitude which is impossible without a stall not causing this whole event. My method of flying would have been to hold about 2 degrees nose attitude up and hold altitude as would have all of my pilot friends. Adjust power as necessary to maintain altitude and everything would have been fine. But if you follow the magenta line that probably isn't possible using the FD as your pitch mode. Why do people hire these guys? It never happened in my era.
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Well, the way it's set up is such that if the aircraft was relatively stable prior to UAS-induced AP disconnect, then it will remain relatively stable without intervention for longer than a more conventional type, because even without AP, the flight control system is still managing trim to keep the aircraft pointing where it was last pointed and the thrust control is locked at the last setting. Strictly speaking, this then gives the crew time to get the books out if necessary and apply the correct procedures. From a piloting perspective that's got to be as simple as it gets, no?
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TurbineD
Where does it say that the pilot's inputs were not inconsistent with flight in Normal Law? Clearly, the pilot, by evidence of the SS traces, is laboring under the illusion that his stick stirring is not going to produce a problem. Has he missed something? Debatable...
The prose in the report does not jive with its own conclusion, that the SS actions of the pilot resulted in unsuitable results. They did in hindsight, but as gums tells us, this manner of control response is more insidious than many will consider.
Failing that, the results of the Pitch commands can just as easily be laid off on inattention to horizon, which is just as culpable...Any unsuitable results that are caused by a collection of miscues are not the result of just one. Do you not see the prejudice inherent in this text, this report?
Do you not recall the endless discussions regarding the pilots initial Nose Up commands interspersed with Nose Down? The discussion re: a lack of initial response of the aircraft? Sluggishness? Where is that? Only the "emphatic" and "inappropriate" NU......
As to:
That is in quotations as it is intended to be a consideration, a possibility offered to frame a possible accusation of malfeasance.
The final decisions made as to the manner and content of this report is up to......Politicians. I take it therefore, with some copious quantity of NaCl....
Bill
Quote:
Pg.173: Following the autopilot disconnection, the PF very quickly applied nose-up side stick inputs. The PF's inputs may be classified as abrupt and excessive. The excessive amplitude of these inputs made them unsuitable and incompatible with recommended airplane handling practices for high altitude flight.
Pg.173: Following the autopilot disconnection, the PF very quickly applied nose-up side stick inputs. The PF's inputs may be classified as abrupt and excessive. The excessive amplitude of these inputs made them unsuitable and incompatible with recommended airplane handling practices for high altitude flight.
The prose in the report does not jive with its own conclusion, that the SS actions of the pilot resulted in unsuitable results. They did in hindsight, but as gums tells us, this manner of control response is more insidious than many will consider.
Failing that, the results of the Pitch commands can just as easily be laid off on inattention to horizon, which is just as culpable...Any unsuitable results that are caused by a collection of miscues are not the result of just one. Do you not see the prejudice inherent in this text, this report?
Do you not recall the endless discussions regarding the pilots initial Nose Up commands interspersed with Nose Down? The discussion re: a lack of initial response of the aircraft? Sluggishness? Where is that? Only the "emphatic" and "inappropriate" NU......
As to:
Quote:
"He tried the entire while to drop the nose, by pushing the Stick forward".
"He tried the entire while to drop the nose, by pushing the Stick forward".
The final decisions made as to the manner and content of this report is up to......Politicians. I take it therefore, with some copious quantity of NaCl....
Bill
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"Clearly" to whom? Your supposition is based on the idea that the inputs were the result of a rational thought process, and unless your skillset includes clairvoyancy - this is something that neither yourself nor any of us can know.
That is in quotations as it is intended to be a consideration, a possibility offered to frame a possible accusation of malfeasance.
Finally, the BEA's staff are not politicians, they are civil servants - just like their counterparts in the NTSB and AAIB. If you do not understand the difference, then I'm a little worried.
Seriously, let this one lie and focus on the B787 issues Bill - I've actually been enjoying some of your input there!
Last edited by DozyWannabe; 6th Mar 2013 at 22:38.
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The chronic consistency of Nose UP? Very bad. The "stirring"? Not so much.
Hence my reference to the Horizon. The report condemns the movements, when it was the overall additive result that was the problem.
The results of his manipulation, the excess persistent PITCH was the problem, yet the report "abrupt and excessive" misleads, had he been abrupt and excessive Nose Down, they may have survived.
If you cannot see the nuance, the prejudice, say so. I believe it is there.
Nothing wrong with abrupt, nor excessive, if countered. No harm to the control surfaces, no complaints about the ride, only the attempt to portray the Pilot as clumsy.
TurbineD
What of the Report's mention of "machine" shortcomings, that may have exacerbated the crash's entry? No AoA, Stick invisibility, etc. ?
"It wasn't the airplane that caused this..."
Hence my reference to the Horizon. The report condemns the movements, when it was the overall additive result that was the problem.
The results of his manipulation, the excess persistent PITCH was the problem, yet the report "abrupt and excessive" misleads, had he been abrupt and excessive Nose Down, they may have survived.
If you cannot see the nuance, the prejudice, say so. I believe it is there.
Nothing wrong with abrupt, nor excessive, if countered. No harm to the control surfaces, no complaints about the ride, only the attempt to portray the Pilot as clumsy.
TurbineD
What of the Report's mention of "machine" shortcomings, that may have exacerbated the crash's entry? No AoA, Stick invisibility, etc. ?
"It wasn't the airplane that caused this..."
Lonewolf_50;
I think these are good questions / discussions on important & relevant matters which still have lessons to teach even as AF447 has been thoroughly dissected, (same thread, for context - slight shift in focus, etc). This is about airmanship, aerodynamics, systems knowledge and, most importantly, effort, a.k.a. "keeness", in terms of what one puts into learning one's craft and profession. So this applies currently and widely.
I've numbered your paragraphs for easy reference. The following is one pilot's experience / interpretation and therefore isn't definitive. I know you know this!
1. (Note: Conversion or Transition course footprints for new types, say A320 to A330, B737 to B767 or A320 to B777 etc, are usually 56 days give or take. Line Indoctrination flying, (regular routes with passengers with a line-indoc captain in either seat depending upon if the candidate is F/O or Captain) is usually included in this footprint but factors can extend this time although it's rarely less.
With that in mind, once the transition course is completed pilots flying long-haul overseas routes in western-built B777/B747/B767/B757/A340/A330/MD11, whether new on the airplane or have been on a long time, are generally working three trips per month, sometimes with a domestic filler. Long haul monthly hour limits vary between 80 and 95hrs with slight variations either way. That usually isn't hard (stick) time as there are 'flight-time guarantees' sometimes built into the schedule. Actual, logged stick time for most of these pilots (domestic & international) is usually about 600 - 1000hrs per year depending upon the nature of the operation.
The takeoff and the late approach / landing phases are almost always hand-flown. These two phases are the only portions of the flight which are hand-flown. It is illegal to hand-fly in RVSM airspace, complicated SIDS and STARS require precise navigation and altitude/speed control and generally the crew is tired at the end and the engagement of the autoflight system is of great value. So the hand-flying portion of most all flights lasts between 8 and 15 minutes, obviously with outliers where pilots choose (and are permitted) to hand-fly the entire departure and climb to cruise altitude, and the descent, approach and landing at destination.
The breakdown is roughly three minutes for the takeoff and initial departure. Takeoff lasts less than 1 minute, initial climb and establishing enroute about six to eight minutes but the autoflight is almost always engaged right after takeoff, mainly for reasons of navigation/speed/altitude precision and crew workload. There is nothing preventing hand-flying of the departure but everyone needs to be right on top of things to do so. The workload is higher but for a good crew that is not a problem.
The descent and approach phases are almost always flown on autoflight with disconnection around 400ft above airport elevation. Autolands are rarely carried out except when required. Autoland works extremely well. Hand-flying the late approach, (FL100 or below) is rare but is usually permissable and a lot of fun as well as very good practice but the same constraints apply so if one disconnects it's later in the approach phase...8 minutes is a reasonable estimate.
This phase (FL100 / arrival), usually lasts about 12 to 17 minutes depending upon the terminal.
From the FAF / OM, (Final approach fix or Outer Marker, (for others, about 4nm to the runway)) to touchdown is usually just over 2 minutes. From 400ft to t/d is about 40 to 50 seconds.
Based on these numbers, long-haul pilots are getting about 3 minutes of hand-flying on takeoff and about 50" of hand-flying on approach. If crews fly three long-haul trips and one domestic that's usually eight legs, perhaps ten and at the most a dozen legs per month. The flying is usually shared between Captain and F/O. At some carriers the third or fourth crew members are regular F/Os or Captains while other carriers use what are known as "Relief Pilots - RPs" who occupy the front seats only in cruise and are not permitted to sit up front below cruise altitudes. This has more to do with cost than anything else but the point is, the tiny time available for hand-flying is shared between at least two pilots, possibly three.
Per trip the available hand-flying time for the crew is approximately:
Takeoff and initial departure: Max 6 minutes, min 3 minutes;
Approach and landing: Max 8 minutes, min 1 minute
Per month the time is about Max 56 minutes, minimum 16 minutes.
For 11 months approximately, (can be less, depending...), the available hand-flying time is about 10hrs 15minutes max or about 3hrs minimum.
For the discussion let us say it is shared between just the two pilots up front.
Divided between the two pilots, hand-flying time for a long-haul pilot is just over 5hrs per year max and about an hour and a half minimum. The rest is flown on autoflight.
2. My sense of "level flight" was as you have said, the IVSI and Altimeter, but definitely not 'g'. Any "g" felt always signals a transition and one always waited for stability while watching/reading the instruments, almost always for verification of expectations and not to see what the airplane was doing.
3. I don't think that for a pilot the pitch / power and performance equation governs how one flies. I think it just has to be experienced and then the intuition comes quickly in ab initio work as well as transition work. I think this kind of knowledge explains afterwards what happens when one flies and so I wouldn't know how to teach it. I think one can only teach (or cause to learn) what it looks like but one can't teach what it feels like. I think that that kind of aeronautical knowledge-building goes right back to ab-initio work when one begins to learn how to fly. Those are the connections being made when one is being taught attitudes, slow flight, stalls and forced landings, (the glide). It is very difficult to teach that stuff (pitch & power) on transport airplanes first because the same power settings can result in different speeds, (Davies) but mainly because the changes are too tiny and the outcomes too large to appreciate the real connection. That's what's meant for example, by "tiny changes in pitch result in massive climb or descent rates". You don't see that in a little airplane, you just see the speed drop off if you pitch up and don't add power or the nose drop if you reduce power and it becomes (or should!) an "aha" moment. It works the same in heavy transports but at much different scales and effects which make it very difficult to demonstrate, (and one shouldn't be demonstrating such work at that stage anyway!).
4. My experience from the DC9 through to the A340/A330 was to fly pitch and power, and both thrust levels and trim complemented this intuitive learning, aided by some very patient captains and as well as by some who weren't patient at all. The A320/A330 were flown exactly the same way but the feedback loops were different but the sound of the air going by the airplane, pitch attitude vs power setting and one's feeling in the seat were the same. Clandestino has commented that the transition back to manually-operated trim (from the AB autotrim) was a non-event and I would agree that it would be easy to pick up say on a B777 or B767, (it might be more challenging if one had never flown non-AB aircraft).
The problems to overcome while transitioning to an Airbus are twofold: The fear of disconnecting, and the fear that it will do something you don't want. Both fears are fought by disconnecting everything regularly and hand-flying where one's company's policy permits. It takes work, study and patience to learn the airplane and it's not as straightforward as the B767 or B777. One does not put the books on a shelf, sit back and wait for someone else to teach them every six months in the sim (or in the office). But I am increasingly hearing of such things as well as hearing that not many pilots disconnect anymore. I think that's a problem.
On learning, on pitch/power and bringing keenness and enthusiasm to the profession for life-long learning, others will hopefully have different views to contribute.
PJ2
1. Once the conversion course is over, who is flying, and how often? Considering recency and frequency of training and prifociency in flying: who is flying and how, when they are flying and particularly when they are hand flying?
2. (regarding AF 447 and a few other UAS events, without airspeed indications, you don't have a critical performance instrument, but you do have available in this case both pitch and power information, and you have both altimeter and VSI to get a sense of "level" or '1 G' flight, or something other than that).
3. Last of all, if like most pilots you are initially taught the above forumula, and imbed that relationship first, how many reps of a different conceptual approach do you need in order to fly "G" or "flight path" rather than pitch using your hands and feet, and internalize that? Varies with each pilot, I suspect.
4. I'd be interested to hear from those who do pilot training and conversion comment on the above. When pilots actually fly the Magic Bus, are the pilots flying pitch and power?
2. (regarding AF 447 and a few other UAS events, without airspeed indications, you don't have a critical performance instrument, but you do have available in this case both pitch and power information, and you have both altimeter and VSI to get a sense of "level" or '1 G' flight, or something other than that).
3. Last of all, if like most pilots you are initially taught the above forumula, and imbed that relationship first, how many reps of a different conceptual approach do you need in order to fly "G" or "flight path" rather than pitch using your hands and feet, and internalize that? Varies with each pilot, I suspect.
4. I'd be interested to hear from those who do pilot training and conversion comment on the above. When pilots actually fly the Magic Bus, are the pilots flying pitch and power?
I've numbered your paragraphs for easy reference. The following is one pilot's experience / interpretation and therefore isn't definitive. I know you know this!
1. (Note: Conversion or Transition course footprints for new types, say A320 to A330, B737 to B767 or A320 to B777 etc, are usually 56 days give or take. Line Indoctrination flying, (regular routes with passengers with a line-indoc captain in either seat depending upon if the candidate is F/O or Captain) is usually included in this footprint but factors can extend this time although it's rarely less.
With that in mind, once the transition course is completed pilots flying long-haul overseas routes in western-built B777/B747/B767/B757/A340/A330/MD11, whether new on the airplane or have been on a long time, are generally working three trips per month, sometimes with a domestic filler. Long haul monthly hour limits vary between 80 and 95hrs with slight variations either way. That usually isn't hard (stick) time as there are 'flight-time guarantees' sometimes built into the schedule. Actual, logged stick time for most of these pilots (domestic & international) is usually about 600 - 1000hrs per year depending upon the nature of the operation.
The takeoff and the late approach / landing phases are almost always hand-flown. These two phases are the only portions of the flight which are hand-flown. It is illegal to hand-fly in RVSM airspace, complicated SIDS and STARS require precise navigation and altitude/speed control and generally the crew is tired at the end and the engagement of the autoflight system is of great value. So the hand-flying portion of most all flights lasts between 8 and 15 minutes, obviously with outliers where pilots choose (and are permitted) to hand-fly the entire departure and climb to cruise altitude, and the descent, approach and landing at destination.
The breakdown is roughly three minutes for the takeoff and initial departure. Takeoff lasts less than 1 minute, initial climb and establishing enroute about six to eight minutes but the autoflight is almost always engaged right after takeoff, mainly for reasons of navigation/speed/altitude precision and crew workload. There is nothing preventing hand-flying of the departure but everyone needs to be right on top of things to do so. The workload is higher but for a good crew that is not a problem.
The descent and approach phases are almost always flown on autoflight with disconnection around 400ft above airport elevation. Autolands are rarely carried out except when required. Autoland works extremely well. Hand-flying the late approach, (FL100 or below) is rare but is usually permissable and a lot of fun as well as very good practice but the same constraints apply so if one disconnects it's later in the approach phase...8 minutes is a reasonable estimate.
This phase (FL100 / arrival), usually lasts about 12 to 17 minutes depending upon the terminal.
From the FAF / OM, (Final approach fix or Outer Marker, (for others, about 4nm to the runway)) to touchdown is usually just over 2 minutes. From 400ft to t/d is about 40 to 50 seconds.
Based on these numbers, long-haul pilots are getting about 3 minutes of hand-flying on takeoff and about 50" of hand-flying on approach. If crews fly three long-haul trips and one domestic that's usually eight legs, perhaps ten and at the most a dozen legs per month. The flying is usually shared between Captain and F/O. At some carriers the third or fourth crew members are regular F/Os or Captains while other carriers use what are known as "Relief Pilots - RPs" who occupy the front seats only in cruise and are not permitted to sit up front below cruise altitudes. This has more to do with cost than anything else but the point is, the tiny time available for hand-flying is shared between at least two pilots, possibly three.
Per trip the available hand-flying time for the crew is approximately:
Takeoff and initial departure: Max 6 minutes, min 3 minutes;
Approach and landing: Max 8 minutes, min 1 minute
Per month the time is about Max 56 minutes, minimum 16 minutes.
For 11 months approximately, (can be less, depending...), the available hand-flying time is about 10hrs 15minutes max or about 3hrs minimum.
For the discussion let us say it is shared between just the two pilots up front.
Divided between the two pilots, hand-flying time for a long-haul pilot is just over 5hrs per year max and about an hour and a half minimum. The rest is flown on autoflight.
2. My sense of "level flight" was as you have said, the IVSI and Altimeter, but definitely not 'g'. Any "g" felt always signals a transition and one always waited for stability while watching/reading the instruments, almost always for verification of expectations and not to see what the airplane was doing.
3. I don't think that for a pilot the pitch / power and performance equation governs how one flies. I think it just has to be experienced and then the intuition comes quickly in ab initio work as well as transition work. I think this kind of knowledge explains afterwards what happens when one flies and so I wouldn't know how to teach it. I think one can only teach (or cause to learn) what it looks like but one can't teach what it feels like. I think that that kind of aeronautical knowledge-building goes right back to ab-initio work when one begins to learn how to fly. Those are the connections being made when one is being taught attitudes, slow flight, stalls and forced landings, (the glide). It is very difficult to teach that stuff (pitch & power) on transport airplanes first because the same power settings can result in different speeds, (Davies) but mainly because the changes are too tiny and the outcomes too large to appreciate the real connection. That's what's meant for example, by "tiny changes in pitch result in massive climb or descent rates". You don't see that in a little airplane, you just see the speed drop off if you pitch up and don't add power or the nose drop if you reduce power and it becomes (or should!) an "aha" moment. It works the same in heavy transports but at much different scales and effects which make it very difficult to demonstrate, (and one shouldn't be demonstrating such work at that stage anyway!).
4. My experience from the DC9 through to the A340/A330 was to fly pitch and power, and both thrust levels and trim complemented this intuitive learning, aided by some very patient captains and as well as by some who weren't patient at all. The A320/A330 were flown exactly the same way but the feedback loops were different but the sound of the air going by the airplane, pitch attitude vs power setting and one's feeling in the seat were the same. Clandestino has commented that the transition back to manually-operated trim (from the AB autotrim) was a non-event and I would agree that it would be easy to pick up say on a B777 or B767, (it might be more challenging if one had never flown non-AB aircraft).
The problems to overcome while transitioning to an Airbus are twofold: The fear of disconnecting, and the fear that it will do something you don't want. Both fears are fought by disconnecting everything regularly and hand-flying where one's company's policy permits. It takes work, study and patience to learn the airplane and it's not as straightforward as the B767 or B777. One does not put the books on a shelf, sit back and wait for someone else to teach them every six months in the sim (or in the office). But I am increasingly hearing of such things as well as hearing that not many pilots disconnect anymore. I think that's a problem.
On learning, on pitch/power and bringing keenness and enthusiasm to the profession for life-long learning, others will hopefully have different views to contribute.
PJ2
Join Date: Jul 2002
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Until that was done there was absolutely no reason to start manipulating the stick.