If you are puzzled by crew behaviour in Air France 447, perhaps a quick read of this will provide food for thought.
That article's not about Air France 447, it's about the airline training status quo, the kind of training the Air France crew would have received.
Ultimately, it's about the regulators' failure to modernise training requirements as the aeroplanes themselves have been transformed.
There is a case for saying that aeroplanes are getting better all the time (I would argue that is indisputable), but pilot competency is in reverse.
It's not the pilots' fault, however. And it's not just me being an old grump and saying "things aint what they used to be".
Recurrent training is the same today as it was for Lockheed Constellations in the 1950s. As Dr Kathy Abbott says in my article, pilots are being given fantastic tools and then not taught to understand nor manage them.
on June 3, 2011 1:41 PM | Reply
Our industry knows better than to speculate before a final accident report. Anyone (including the media) seeking professional airline insight are likely to turn to David Learmount. The term 'pilot error' is meaningless, especially in a proactive SMS.
We did not reduce our industry accident rate every year since aviation began by sensationalist or tabloid speculation.
How on earth can we conclude from an interim report. This is getting out of hand.
on June 3, 2011 6:01 PM | Reply
How about a big red button that lets the pilot take control from the computer.
on June 3, 2011 9:29 PM | Reply
I think QF32 back in November shows that there are pilots with a great deal of technical knowledge about their planes. Richard DeCrespigny and the rest of the pilots on board displayed a deep knowledge of the technology in the A380 that no doubt saved lives.
on June 6, 2011 9:09 AM | Reply
In all fairness Adam-330, Learjet may be, as he implies, a grumpy ol’ bollox, but generally, though not always, he is on the right sight of the drag curve and he is our grumpy ol’ bollox, is he not ?. I had a few coincidental seminar glasses and après pints with him in Bruxelles on Nov 23 2006, though he stuck to quelques verre vin rouge, if I recall. I was not impressed with drinking wine in a pub, that is a drinking problem, clearly. Still, discounting that faux pas, I found him informed, articulate and convivially good company in general. He reminds me of my sim-gen(similar generation) ex-RAF uncle in fact. Learjet, is, in essence, the best of England’s fair play, in my Irish opinion.
More seriously Adam-330, your tense is incorrect, it GOT, not is, out of hand of sidestick on June 1 2009. That is the point surely ?. AF-447 is aviation’s greatest FDR/CVR retrieval effort in history, kudos to the BEA and Wood’s Hole Oceanographic literal Titanic effort for this Honeywell treasure of tragedy from the deep. In human history, no voice nor flight data has been retrieved from such bone dissolving depth. Remember the previously unbelievable accident of an American Airlines A-300-600R of AA-587 in New York on Nov 12 2001 ?, Remember the VA debate then ?, mirroring the stall debate now. Consider the following twain that did not meet. To wit :, “VA,- is the speed at or below which, the aircraft will stall, before excessive G-forces can build up”=Jeppesen Sanderson Training Products- Commercial Manual,1-12, 9th Edition 1994. My FAA PPL was 09-09-94 for full disclosure. Now, consider the commercial-professional FAA Part 121 definition, “VA- is defined as the speed above which maneuvers involving full application of rudder, ailerons, or elevator, or maneuvers involving angles of attack near stall should be avoided.”=NWA 747-400 Cockpit Operating Manual,1.6.5, October 14 2005. This was probably written by a clever lawyer, stupid pilot or both. This was professionally nearly 4 years after AA-587. And still, elevator is mentioned last and rudder and ailerons take pole position, despite ailerons and rudder having the inverse square root of zero to do with VA and elevator has ALL to do with VA. Einstein defined insanity as constant repetition of the same behaviour in expectation of a different result. QED to that.
V/S-Fast forward to June 1 2009 -Why did the AF-447 command FO , correctly demand roll left to correct the turbulence roll and simultaneously incorrectly demand pitch aft/up ? Having clumsily flown an A-320/340 to landings in 2007 from 5000ft +/-“I suggest”, it is the sidestick/mini-manche in itself. It is optimal for low energy states of takeoff and landing but far from a precision hand flown control demand manipulator in the coffin corner in an ambiguous legal mode of operation above and outside the laws as demonstrated. An assumed outlaw in effect.
For reference, I refer to my Boeing DNA. When executing steep turns in a B-744 simulator PC, I lower my type-rated left seat, armrests. This provides a fulcrum for my elbows and forearms and a peripheral visual reference point for my hand on the yoke for very accurate pitch control. At 280kts in AP-AT equilibrium, I disconnect the AP-AT to manual-moi and I roll to the sub-optimal right, from my left seat. Over 30 degrees bank/1.15G=1.07 VS=7% increase. I squeeze a few extra EPR digits on the “mannettes de commande de poussee” , known as throttles and haul increasing aft-back pressure to 45-60 degrees bank/2.0G=1.41 VS=41% increase. I bank with both hands on the yoke and eyes on the PFD,2.5-5 degrees pitch. 10 degrees lateral, before start heading, I roll out, pitch down and power back-“NO TRIM ALLOWED”, as this is a biceps+/triceps/brain- work-out. For a PT, I’ll do the same from the right seat, to the right optimally and sub-optimally to the left.
AF-447’s, PF-demand rolled left and demand twitch/pitched-up to zoom climb to stall, why ?, perhaps a momentary regression to non-FBW training days at lower altitudes in a non-routine Alternate Law A-330 ?, who knows really ?. But consider PF’s correct realisation of an impending stall of pitch demanding forward from previous aft from 7000FPM to 700FPM V/S, albeit, then in the ISA+ stall corner of FL380 and pitching down. His reaction is to TOGA, after the stall fact, when the optimal-survival action is TOGA before stalling and idle if actually stalled to avoid a Mach-migrating shock stall MAC% migrating full stop. In the stall corner, throttles and stick should move in the same direction. Why then did he counter-intuitively pitch demand aft in an actual stall ?. Could it have been Alpha-Floor expectation bias ? despite the fact of his ship being in “Alternate Law” in which Alpha-Floor is applicable only in Normal Law ? Usually Alpha-Floor is on full display at the Le Bourget and Farnborough Airshows when pitch demanding aft manipulation not only provides TOGA, but pitch to max alpha, certainly inspiring rubber necking confidence and perhaps, a false sense of complacent security ?. Basically ,not only had he never actually fully-stalled a heavy jet or light jet, even in a sim, like most commercial non-test pilots, but despite his throttle to TOGA reflex, he possibly assumed “confirmation bias of assuming the expected” of the NORMAL LAW, of which he “approach to stall” trained to, and would “pitch-up” to an Alpha-Floor getaway, as per normal law expectation of posited confirmation bias.
And conspicuous by its absence from the stall debate is the FO PF’s secondary action attempt to pick up a stalled dropping right wing with AoA increasing left aileron roll demand without rudder’s pedal yaw-roll demand application being even mentioned by the BEA ?. Being rudder-shy has no place in a stall, being aileron-shy has. It certainly partially explains why they impacted the Atlantic Ocean heading west instead of northeast on track.
My BEA Recommendations :
(1)-Airbus modify and clarify their legal Control Law position between Direct, Normal and Alternate Law without current Normal-Auto-Alternate Law demonstrated ambiguity. Until a control law “Decree Nisi-Divorce” is executed in de-jure effect, there should be an inhibition on all auto stabiliser trim in Alternate Law. Auto is auto and manual is manual and let never the twain meet again. Also, to make the activation threshold between Alternate Law and it’s subset of Abnormal Attitude Law more fluid and based on AoA vane incidence, rather than “relatively” academic inertial upset, as ADIRU input can be rejected for being in a stall, as it was in the AF-447. E=MC2 =IRS Physics more than Muscular Physical.
(2)-Incorporate a pitch trim thumb switch/trigger on the sidesticks, to be used in Alternate Law. And if used inadvertently or deliberately cause AP disengagement to Alternate Law with ECAM annunciation. Auto stabiliser trim, in manual flight is a clear and present danger. Expensive mod ?, yes !, but not as expensive as an AF-447 sequel.
(3)-A stall condition with an IAS below 60kts causing the stall warning to be ”academically” invalid as AoA cannot be calculated accurately below that speed is AoA-Absurd. Even though the warning stops, the stall and it’s gravity are still V/S valid. A stall ain’t over till the warning stops singing. What matters is the AoA vane’s rotary resolver-transformer that functions as a transducer, not the ADC’s correction calculated IAS.
My AF Recommendations :
(1)-A Stall is a fall to be avoided in operation but trained for recurrently with a cardiac arrest or stroke seizure scenario having the Captain or FO grabbing and pulling the stick to a stall and the startled, but fit crewmember executing a recovery. That is, idle thrust and aft stick gradually in slow increments, never continuous until all ALL Airbus control laws have been declared “DECRI NISI-DIVORCED” from current muddled auto-man-auto status quo. If the nose has pitched down, the recovery has already begun. Relax and take stock of the workshop. FEET ON FLOOR, HANDS ON KNEES, EYES ON PFD, QED!.
(2)-Recover wing drops with rudder ONLY, initially in the PFD blue direction and have the resolved discipline to hold one’s foot input. In effect, back to basics. Think as a muscle memory upset recovery. That is, push to unload the wings, power to preserve speed and altitude, rudder to right the lift vector and hold it without AA-587 type rudder reversal in which the PF FO put his foot in it. Then roll to adjust track’s heading when righted with the PFD’s blue side up. “Push-Power-Rudder-Roll!” – “Go !”, train with eyes closed to perfect the accuracy. I think and do, therefore, I am. Also, while nobody wants an altitude bust citation, such a bust in a TCAS-RA ATC world affords a good margin of error, so relaxevous svp, encore !.
(3)-Consider aerobatic training and indeed bungee jumping to maintain skill and manage fear in unusual attitudes. My first bungee jump was Den Haag/The Hague’s Scheveningen beach. You tube “Scheveningen-Nordzee, 14-06-09. Gravity P1, Connolly P2”. I was initially terrified, but recovered to do a sequel in July, along with wife Co-Pilot, who insisted on her own solo from my co-joined CRM offer. I videoed her solo too. Confidence is capital, never in deficit. As she always says to me in her apt long-suffering way, “Your delay is my holiday !” I say, “Humour must always remain right side up!”. I shall do my best.
As David L implies, our understanding of our accumulated knowledge is moving in inverse proportion to technology’s advance. And remember, little things tell us lots. AF-447 with an impact G/S of 107 was a non-flying pig with a flying stabiliser, ironically. If the stabiliser had Mach/load migrated, AF-447 would indeed have been the proverbial grand piano falling from the top floor with a G/S of zero. But AF-447’s rejuvenation is anything but a zero sum game. For that, in hand, we should be grateful. Also, if the Gods of Icarus decreed that this disaster of incredulity must happen for aviation to advance, it is fortunate that it happened to Air France rather than, say, Air China. Because, if it did befall Air China, Airbus would not be able to use Asian ignorance for cover of its assumed superiority of its demonstrated latent failure design shortfalls via a so-called “world class” carrier. What other class of carrier is there on planet Earth ? With the fall of AF-447, they are no longer afforded such convenient cover. Which all goes to show, that in a cynical world, some accidents are more equal than others. And who would have thought that a deficient Thales Pitot heating element could have revealed so much about the hierarchy of legal authority ?. But revolution always begins from the weathered working elements, as Thales shows. The irony is that Henri Pitot and Thales are French and USA’s Goodrich, the original pitot provider replaced by Thales, is now back in vogue replaced by Goodrich again, thus demonstrating that style is permanent and fashion is fickle and transitory and pride always precedes a fall. Also, Habeas Corpus “Alternate Law” has proven to be a sub-optimal appellant court advocate of the mort subite et violante, Voilla , QED!. Let us appeal to reason before law. Then, and only then, of it and never, by it.
on June 7, 2011 2:10 AM | Reply
With long haul flying, IMHO, we need to address what "logged" flying hours really mean.
In AF447, the No.3 pilot if I remember had about 800 hours on type.
That's about 80 flights, and I guess about 10 or so take offs or landings.
Is this enough hands on flying I ask?
A short haul Airbus no.2 driver with same hours has probably 250 to 300 sectors in his log and perhaps 50 landings or take-offs.
Who has the more experience and who might handle an unusual situation better?
We are comparing two pilots with similar times, but I suggest long haul flying does not provide enough hands on flying!
Where it is possible, perhaps the answer is to give pilots a mix of short haul and long haul time to maintain airmanship skills, even though those skills in many cases are intuitive for the lucky few who are so blessed.
on June 7, 2011 11:22 AM | Reply
Either way Andrew, it is the sorties of takeoffs and landings that count for currency, rather than the relatively meaningless hours accrued. But, as you say, it is true that long haul flying does erode basic handling skills in general with a traditional yoke and in particular with an Airbus sidestick. Perhaps revised control laws can clarify an offside-stick rule that keeps the handling pilot on the periphery?. Short haul running up a down escalator does aid handling proficiency obviously.
Still, long haul loss of control is not exclusively the preserve of Airbus. On June 28 1998, United Airlines 863, a Boeing 747-400 with 307 on board departed San Francisco’s Runway 28R for Sydney, with the FO as PF. After takeoff it entered a low Strata-Q cloud layer and then the #3 P&W N2 surged and shook the ship so violently that the crew were unable to focus on the PFD and EICAS. In the meantime, San Bruno mountain at 1576 amsl, loomed a few miles ahead and to the right of the extended centerline shrouded in San Francisco’s perennial sea fog for good measure. The ship yawed right and the FO, incorrectly applied left aileron, which was of course insufficient to arrest the yaw and the ship entered a skidding right turn toward the mountain. . In addition to the deflected ailerons are 5 flight spoilers deployed, further eroding climb performance, when the yoke is deflected by 9 degrees. This feature, normally on a good day, kills lift to lower the wing and adds some drag to counter the adverse yaw effect. Then the stick shaker began to clatter in addition to the previous surge shaking. The ground proximity warning then began its verbal admonishment , “Terrain !, Terrain !, Pull Up!”. In response to the, eh, “urging” of other pilots on the flightdeck, the FO pulled up the nose even further and converted into altitude what little excess airspeed remained, which by chance turned out to have been the right thing to do. They cleared San Bruno mountain by 100 feet and were so low that they went off ATC radar, causing them to momentarily consider a crash. They eventually shut the engine down, dumped fuel and returned to land in San Francisco after setting off quite a few car alarms with low level MCT.
Had this ship been lost, United’s trip to Chapter 11 protection from creditors would have occurred much sooner than it did in December 2, possibly skipping that and going straight to Chapter 7 liquidation. Quite a price to pay for being rudder shy. Crab to track on approach and rudder slip and opposite aileron to runway align keeps one’s feet and hands current. As United 863 illustrated, roll before rudder, leads to skid drag, nearly skid stall, just narrowly avoiding skid row.
on June 7, 2011 8:02 PM | Reply
It was over reliance on the automated systems which was their undoing.A pilot of an earlier era, twenty years or so would have first disengaged the autopilot and flown manually for any remedial action.
In an incident on a flight from Singapore to Australia a few years back, the Qantas Airbus A330 suffered un-commanded autopilot function resulting in climb, followed by descent of hundreds of feet resulting in broken bones and severe injuries to occupants. Hereto, throughout the investigation by the crew in the air the autopilot remained engaged, till identified as the culprit. What was the reluctance in disengaging it in the first place?
Our senior captains have got used to flying manually in the six monthly simulator checks only. There is hesitation to hand fly. Besides even in the simulator, leniency is exercised on the exertion levels of these guys.
I would also like to discuss the role of the captain who never took command of the aircraft till the crash. First of all with a storm looming on the horizon and discussion in his presence of it, he should have hung around until it was past them. The second pilots uneasiness is reflected in repeated calls to him to return to the cockpit. A confident crew wouldn't think twice of the captain's absence. and when the captain turns up, he watches all the fiasco only. Four minutes is an eternity in aircraft emergencies.
We can all talk of the thunderstorms and turbulence there, the scenario if you can picture in your mind is pretty tough, the instruments must have been unreadable in the turbulence and with rain, thunder, hail, lightning, and electrical arcing on the windshield, enough to shake the firmest. On top of this the instruments were giving differing stories on different panels. It was therefore essential for the captain to fly that aircraft and not let the junior most crash it in the ocean.
on June 8, 2011 5:23 AM | Reply
Understanding crew behaviour? I think understanding aircraft behaviour would me more apt. How is it that the reporting of this incident has been funnelled straight in to blame the pilots with reports that amount to little more than summaries.
It is clear that there is a lot at stake for Airbus and Air France on this and the utterly premature conclusions that it was the pilots wot dun it and tired platitudes of outdated training that isn't up to scratch only attempts to divert attention from the bizarre and perplexing, characteristics, behaviour and design of the A330 during such an upset.
So far I surmise that the crew were fighting an aircraft that did little more than confuse the crew and attempts to at the "what were they thing" style of reportage are utterly unreasonable and disingenuous in the current circumstances of the extremely limited, ambiguous and selective information that has so far been released.
The upset seems to be due to a deficient air speed sensor design that was already assessed as such and subject to airworthiness directives and there were questions over a particular configuration of weather radar system fitted to the A330 as per the time proximate Qantas incident.
Why the crew were unaware of the severity of the weather (i.e. why didn't the radar provide accurate returns) and why the aircraft's time immemorial air pressure differential system design failed them in just such circumstances that it was designed for is what really should be in question.
on June 8, 2011 9:52 PM | Reply
I agree that there is certainly more than meets the eye and it is also evident what is at stake for Airbus and Air France.
I find it hard to believe the crew error highlighted in stall recovery handling, taught to a pilot in basic airmanship lessons, the technique of which remains the same and is ingrained through transition to various aircraft. The FDR bears the error out.
But here we are dealing with professional pilots for a major carrier. The automation in the A330 has acquired a reputation for inconsistency as there have other serious incidents.
How did the aircraft stall? Obviously the speed dropped unnoticed/or noticed erroneously through faulty speed sensors, when the autpilot and autothrottles disconnected. I agree that sitting comfortably at home and in hindsight one can feel very superior in dishing out all this crap but their saving grace can only come through the severity of the storm which compounded this emergency dramatically, probably making the instruments unreadable in the first place and as you have indicated, "to divert attention from the bizarre and perplexing, characteristics, behaviour and design of the A330 during such an upset. "
"So far I surmise that the crew were fighting an aircraft that did little more than confuse the crew and attempts to at the "what were they thing" style of reportage are utterly unreasonable and disingenuous in the current circumstances of the extremely limited, ambiguous and selective information that has so far been released."
I agree with the above statements in inverted commas.
The weather radar from what I have read performed as it should. In fact it enabled the diversion to the left initially after which all hell broke loose.The crew were very much aware of the weather and had also briefed the cabin staff.
I hope I am wrong in assigning blame to the captain for not taking control of the aircraft when he could(if possible)and his apparent carelessness in leaving the aircraft to the copilots when it must have been showing on the radar returns(if functioning properly). The weather was discussed in his presence.
I also fail to understand how the junior most of the lot was at the controls except in the last moments.
on June 8, 2011 11:00 PM | Reply
Mohmmad Syed and Bob ,I think the shivering Thales Pitot heating was the catalyst exposing the other latent-dormant A-330 design failures, in a "through the looking glass" parallel of the A-300-600R of AA-587 of Nov 12 2001. Then, a JAL B-744's wake turbulence exposed the critical limits/latent-dormant failure of the A-300-600's "Fixed Ratio" rudder changer,aided by a FO with a high speed rudder habit.Probability doth the twain meet. Unlike it's earlier A-300 B2/B4 series that had the B-747 Classic "Ratio Changer", this was a direct result of the deletion of outboard ailerons on the A-310 and A-300-600. Notice that the A-330/340/380 widebodies all have split outboard ailerons,by 3 on the A-380 making a nominal inboard aileron in all. They learned from the attrocious X-wind performance of the A-310/300-600, long before AA-587 got it's tail kicked off in 7 New York seconds.
Consider this letter in AW&ST from a probable North American skipper "by tone" of a probable North American carrier, albiet devalued by it's anonymity, alas.
To wit :
I would like to offer my comments and perspective with regard to the Air France Flight 447 accident. I have been a A-330 captain since 2003 and have over 4500 hours in the aircraft. While many A-320 pilots undoubtedly have more series time, I believe this probably makes me one of the most experienced A330 pilots in the world.
When asked how I like the aircraft, I tell people that there is likely no easier airplane to take over an ocean, and that the systems design and presentation is superb. That said, the automation is more complex and less intuitive than necessary, and the pilot-aircraft interface is unlike that of a conventional aircraft. Most important with regard to this accident is the fly-by-wire sidestick control. The sidestick itself has a very limited range of motion, making inadvertent over-control very easy. Of even greater significance, the stick itself provides no "feel" feedback to the pilot. That is, unlike a conventional aircraft, the pilot does not get a sense through pressure of how much input is being sent to the control surfaces. The most important advice I give to pilots new to the Airbus is to treat the aircraft not as an airplane, but as a video game. If you wait for the sidestick to tell you what you are doing, you will never get an answer.
Taking into consideration that Air France 447 was at FL 350 (where the safe speed envelope is relatively narrow), that they were in the weather at night with no visible horizon, and that they were likely experiencing at least moderate turbulence, it does not surprise me in the least that the pilots lost control of the aircraft shortly after the autopilot and autothrust disconnected.
Let's keep in mind that these are not ideal conditions for maintaining controlled flight manually, especially when faced with a sudden onslaught of warning messages, loss of autofllght, confusing airspeed indications, and reversion to "alternate law" flight control, in which certain flight envelope protections are lost.
A very bad Airbus design feature is thrust levers that do not move while in autothrust. They are instead set in a detent which would equal climb trust in manual mode. If the pilots did not reset the thrust levers to equal the last cruise power setting, they likely eventually ended up in climb power, making it difficult to reset the proper cruise power setting and adding to what was likely already a great deal of confusion.
But the real problem probably occurred immediately after the pilot flying grabbed the sidestick and took over manually. Unfortunately, airline pilots rarely practice hand-flying at high altitude, and almost never do so without autothrust engaged. As a result, we forget that the aircraft is very sensitive to control inputs at high altitude, and overcontrol is the usual result. Because the Airbus sidestick provides no feedback "feel" to the pilot, this problem is dramatically compounded in this aircraft.
I believe the Air France pilot grabbed the sidestick, made an immediate input (because as pilots, that's what we tend to do), and quickly became quite confused as to what the aircraft was truly doing. This confusion likely was exacerbated by fixating on airspeed indications that made no sense while trying to find a power setting with no airspeed guidance.
When transitioning from autopilot to manual control at altitude in the Airbus, the most important thing to do at first is nothing. Don't move a thing, and then when you do, gently take hold of the sidestick and make very small inputs, concentrating on the flight director (which, in altitude hold, should still have been providing good guidance). Of course, this is much easier said than done with bells and whistles going off all over the place, moderate turbulence and a bunch of thunderstorms in the area. As I said before, treat it like a video game.
So why did the Air France pilot find himself at the limits of sidestick travel, and then just stay there, maintaining a control input that simply could not logically be correct? When things go really bad and we are under intense pressure, it is human nature to revert to what we know from previous experience. Remember, the Airbus flies like no other aircraft in that the sidestick provides no feedback to the pilot. It is a video game, not an airplane.
I believe the Air France pilot unintentionally fell back on all of his previous flying experience, in which aircraft controls "talkedF" to him when he moved them. Distracted by many confusing inputs, he instinctively expected to be able to control the aircraft by "feel" while dividing his attention to address other matters. I've seen it happen in the simulator, and in an Airbus this is a sure way to lose control of the aircraft and is possibly the most dangerous aspect of Airbus design philosophy.
One last note: Airbus pilots often claim that the aircraft "can not be stalled." When the flight controls are in "normal law" this is a reasonably true statement. However, in "alternate law," as was the case here, stall protection can be lost. If we ever practiced this in the simulator, I don't remember it.
Lest anyone think I am blaming the Air France pilots for this accident, let me be clear. Despite all of my experience in the aircraft, I am not the least bit certain that I would have been able to maintain control under the same circumstances. I do feel certain that were you to spring this scenario on pilots in a simulator without warning less than half of them would have a successful outcome. Safely flying the 320, 330 and 340-series Airbus requires something of a non-pilot mindset.
AW&ST Name Withheld
on June 9, 2011 10:25 AM | Reply
David Connolly: I agree with your comments. I think Bob would also like to focus on providing specific problem related training to crews on these aircraft.
Regarding control sensitivity at high altitudes and with no experience on Airbus aircraft, I can only add that on different occasions in my career as an airline pilot, I had to hand fly sectors of as much as 7 to 8 hours because the autopilot could not be engaged on getting airborne, once out of Karachi for Beijing and at another time from Karachi to Athens(night sector). The book required dumping and landing back but this was almost never done in our airline with the B707 equipment in those days. I can attest to the sensitivity of the controls and getting used to it but that aeroplane could do everything almost.
on June 9, 2011 12:52 PM | Reply
Mohammed Syed: Looking at the B-744's MEL- Autoflight Autopilot Systems, "All may be inoperative provided: Flight crewmembers are limited to 5 flight hours per scheduled flight day." When you would have said, "I've just flown in from Karachi and my arms are very tired!", it would not be a feathered Icarus joke. I wonder what the A-320-380 limits are ? At least on a Boeing you can change hands without having to change seats.
on June 9, 2011 4:22 PM | Reply
David C
Regarding your input from the anonymous A330 pilot who wrote to AW&ST, I take issue with some of the things he/she says.
I quote an extract from the letter:
“The stick itself provides no "feel" feedback to the pilot. That is, unlike a conventional aircraft, the pilot does not get a sense through pressure of how much input is being sent to the control surfaces. The most important advice I give to pilots new to the Airbus is to treat the aircraft not as an airplane, but as a video game. If you wait for the sidestick to tell you what you are doing, you will never get an answer.” QUOTE ENDS
Manual flying, in any aircraft type, involves the use of the stick to select an attitude. “Feel” in the stick is not what you use to determine an aircraft attitude. That's purely visual.
When you want to change the attitude, you judge (from training and experience) an angular input to the stick that will provide the rate of change you want, and you remove the input when you can see your attitude has been achieved. Control feel plays no part in your decision that you have achieved your desired attitude: that is purely a visual judgement.
No good pilot relies on “feel”, from any control, to provide them with a selected attitude or speed. S/he may think s/he does but, actually, s/he doesn’t.
If you were to extend this argument in favour of flying by “feel” into other areas of aircraft control technique, you would end up arguing that the seat of your pants should be the final arbiter for what your aircraft is actually doing in IMC. You wouldn’t do that.
This is not about Boeing versus Airbus. You don’t use “feel” to select an attitude on a 747 classic. When you can see you have reached your chosen attitude, you release the stick input and trim. That’s what you do on an Airbus too, except when you release the stick the aircraft provides the trimming.
But while we’re on the subject of Airbus’s control interface allegedly being “like a computer game”, do you have a problem with that? I don’t.
on June 10, 2011 11:46 AM | Reply
Reading through all your "professional" comments, I asked my friends & colleagues still active (FYI, I retired in 1989 flying B747-200)if modern Airbus cockpits had still a gyroscopic ADI & a magnetic compass as I had in all the a/c I have flown.
The answer was "NO"!
And that explains AF447's disaster. Attitude and Power settings will solve your stalling situation. All the rest, Alpha floor, Direct-Normal-Alternate Law, I would leave them to video games gurus. When computers go berserk, and they often do, plain basic flying will give you a good chance to get out of a situation like the AF447 ended up with.
The problem, as David hints, is that modern pilots lack those basic skills. "C'est tout!"
on June 13, 2011 10:26 PM | Reply
Understanding what went on before the Autopilot/Autothrottle disconnect is I believe going to be cruical in this investigation. Did the IAS decay insidiously or did it read high -this may have caused the plane to be in a potentially stalled or near stall condition at the moment of disconnect or did the computer make the plane fly too fast thru turbulent air over stressing the structure? These two questions will be key to understanding what actually happend on board this aircraft.