Thrust levers - moving or not?
BA's alleged ban on Manual Thrust
Hi Goldenrivett,
"I gather the reason was because there were far more "incidents" on the Airbus fleet than any other fleet with low speed during manual flight."
Thanks for the link to that paper. I can only hazard a guess at the identity of the "senior airline manager" in April 2004 to whom M. Scott refers.
By "manual flight", do you mean manual thrust? Up to the end of 2001, I was aware of at least one serious, windshear-related loss of airspeed in manual flight, leading - IIRC - to a firm-ish impact with the runway during the go-around. But that was using A/THR. Maybe the incidents you heard of happened later?
(It may seem perverse, but I was never entirely convinced that the AI policy of using Flaps 3 for A320-series landings when only light or moderate windshear was expected was justified. Except in a strong headwind, the thrust requirement can be lower than ideal. Sometimes the A/THR reduces the power so much in a temporary headwind shear - almost to flight idle in some cases - that the engines take a while to spool up for the inevitable loss of IAS when the headwind dies away. An experienced pilot would never retard the thrust that much at a low height - say, around 100 ft.)
The understandable desire for cross-fleets standardisation created minor problems for the BA Airbus fleet in my day, but I wonder if BA has reassessed its policy since BA762... Differing beasts can't always be ridden the same way. Pilots can and do adapt. I doubt that any pilots are dual-rated on, say, B744 and A380?
"I gather the reason was because there were far more "incidents" on the Airbus fleet than any other fleet with low speed during manual flight."
Thanks for the link to that paper. I can only hazard a guess at the identity of the "senior airline manager" in April 2004 to whom M. Scott refers.
By "manual flight", do you mean manual thrust? Up to the end of 2001, I was aware of at least one serious, windshear-related loss of airspeed in manual flight, leading - IIRC - to a firm-ish impact with the runway during the go-around. But that was using A/THR. Maybe the incidents you heard of happened later?
(It may seem perverse, but I was never entirely convinced that the AI policy of using Flaps 3 for A320-series landings when only light or moderate windshear was expected was justified. Except in a strong headwind, the thrust requirement can be lower than ideal. Sometimes the A/THR reduces the power so much in a temporary headwind shear - almost to flight idle in some cases - that the engines take a while to spool up for the inevitable loss of IAS when the headwind dies away. An experienced pilot would never retard the thrust that much at a low height - say, around 100 ft.)
The understandable desire for cross-fleets standardisation created minor problems for the BA Airbus fleet in my day, but I wonder if BA has reassessed its policy since BA762... Differing beasts can't always be ridden the same way. Pilots can and do adapt. I doubt that any pilots are dual-rated on, say, B744 and A380?
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In conventional aircraft when you make flight path change or thrust change visually the tactile feed back and speed stable behaviour provides additional cue. Airbus FBW in manual flight you fly only by visual cues. The changes to flight path, speed and thrust are visually noticed and effected. Not only there is no feed back in the stick, the flight path stable aircraft does not pitch up or down to speed changes, power changes only large increases will cause a dampened response. In airbus since any displacement of side stick is a demand for change either in pitch or bank the stick needs to be in neutral most of the time, it is essentially intermittent contact flying. Basically in manual thrust in any aircraft pitch changes require thrust change but in airbus you only see and do as your hand will feel nothing. It is different but not difficult. Elevator integrator holds the elevator where ever you leave it and trim catches up automatically. The aircraft is always in trim. But pilot always needs a good scan. It is immaterial whether AP is on you still scan instruments in the same manner but only watch changes happening instead of making. In SFO they never monitored the speed because may be over confidence in automation or it is possible never developed raw data skills in the first place. Design of the automation had nothing to do with it. Any one who has the skill can maintain it with very little practice.
Quote from vilas:
"Basically in manual thrust in any aircraft pitch changes require thrust change but in airbus you only see and do as your hand will feel nothing. It is different but not difficult."
What do you mean by "[in manual thrust] ... in Airbus your hand will feel nothing." ?
(BTW, I agreed with your previous interpretation of the B777 accident at SFO and the B737 at AMS, and the fact that moving throttles are not a panacea for ignorance or complacency.)
"Basically in manual thrust in any aircraft pitch changes require thrust change but in airbus you only see and do as your hand will feel nothing. It is different but not difficult."
What do you mean by "[in manual thrust] ... in Airbus your hand will feel nothing." ?
(BTW, I agreed with your previous interpretation of the B777 accident at SFO and the B737 at AMS, and the fact that moving throttles are not a panacea for ignorance or complacency.)
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Hi Chris,
The incidents I heard of all happened before 2004. They were mostly low speed events during ILS Approaches in good weather. Crews were practicing manual thrust approaches in anticipation of their next sim check.
Due to the number of events, management perceived it was safer to ban manual thrust practice on the line and devote extra sim time for manual thrust practice. I don't know what the current position is.
vilas
The difference is that all clues are visual and there is no priority over any parameter.
On conventional aircraft, "feel" is devoted almost entirely to Angle of Attack control.
Maybe the incidents you heard of happened later?
Due to the number of events, management perceived it was safer to ban manual thrust practice on the line and devote extra sim time for manual thrust practice. I don't know what the current position is.
vilas
Basically in manual thrust in any aircraft pitch changes require thrust change but in airbus you only see and do as your hand will feel nothing. It is different but not difficult.
On conventional aircraft, "feel" is devoted almost entirely to Angle of Attack control.
Last edited by Goldenrivett; 15th Aug 2015 at 18:47. Reason: typo
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@Centaurus it becomes even more weird when you have experienced that the 737 can quite wonderfully use the autothrust in OEI flight as well as keep the rudder where it belongs as well, thus providing full automatic flight.
Is an autopilot rudder channel available on B737? None I've flown. Every QRH I've seen B733/737/738 has instructed A/T off with SE ops. True, if an engine fails in CRZ the A/T will increase and try to maintain speed. I'm not sure how long it will remain connected. On takeoff it will disconnect during climb out.
Question to the AB pilots: when flying an approach with A/T engaged do you follow through on the T/L's? If not where do you have your inside hand? I suspect the B777 Asiana PF had both hands on the yoke; might be wrong.
Is an autopilot rudder channel available on B737? None I've flown. Every QRH I've seen B733/737/738 has instructed A/T off with SE ops. True, if an engine fails in CRZ the A/T will increase and try to maintain speed. I'm not sure how long it will remain connected. On takeoff it will disconnect during climb out.
Question to the AB pilots: when flying an approach with A/T engaged do you follow through on the T/L's? If not where do you have your inside hand? I suspect the B777 Asiana PF had both hands on the yoke; might be wrong.
RAT, according to the reports, the Asiana pilot was having to exert ~80 lbs. force on the yoke as the airspeed decayed towards stall. I think we can safely assume he wasn't doing that with one hand on the throttles 
.
Although not a pilot, I've spent lots of time on the flight deck during flight tests - and observed countless simulator sessions - and the PF has always had one hand on the throttles during approach/landing. I've assumed that was SOP and pilots who flew Boeings were taught to do that.
BTW, I don't think BA 38 (777 that landed short at Heathrow) is particularly relevant to this discussion. Those engines were incapable of producing additional thrust due to the ice-blocked heat exchangers, regardless of how the thrust was being controlled. There was nothing that the pilots could have done to prevent the crash landing.
.Although not a pilot, I've spent lots of time on the flight deck during flight tests - and observed countless simulator sessions - and the PF has always had one hand on the throttles during approach/landing. I've assumed that was SOP and pilots who flew Boeings were taught to do that.
BTW, I don't think BA 38 (777 that landed short at Heathrow) is particularly relevant to this discussion. Those engines were incapable of producing additional thrust due to the ice-blocked heat exchangers, regardless of how the thrust was being controlled. There was nothing that the pilots could have done to prevent the crash landing.
I would say that the Capt under training flying the Asianna B777 at SFO had lost his link between speed and the throttles. He was converting from the A320.
I fear will will see more of these types of accidents in the future as a whole generation of pilots no longer touch the throttles. The thinking is that we're there to back up the autothrottle-- WRONG. I always view the autothrottle is there to back me up. Not possible if the throttles don't move.
Accidents where non-moving throttles may have been a factor-
Tam3054 at Sao Paolo,
Air Inter at Strasbourg
I fear will will see more of these types of accidents in the future as a whole generation of pilots no longer touch the throttles. The thinking is that we're there to back up the autothrottle-- WRONG. I always view the autothrottle is there to back me up. Not possible if the throttles don't move.
Accidents where non-moving throttles may have been a factor-
Tam3054 at Sao Paolo,
Air Inter at Strasbourg
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Yes, but back to my question of AB pilots: if you are making an approach, of any sort, but especially a manually flown approach with ATHR engaged, where is your inside hand?
AB pilots have said that they need to increase their scan to include N1% gauges to monitor the ATHR system. To me this is increased work load at a time you might not find it the most convenient. On some a/c, with PFD and speed tape & speed trend vector display, as speed increases or reduces you can see the speed vector move. If the correct thrust adjustment is made you see the trend vector respond in the opposite sense. I'm not suggesting tunnel vision scan, but this important information is in your central scan. If using ATHR with moving levers you can 'feel' the a/c respond, then see its effect. If manual thrust then you apply the correction yourself and see the result. It's using more senses and having a solid feedback loop in your brain. IMHO you are more 'engaged' with the a/c. It is intuitive. If you have set a datum thrust for the phase of flight you can monitor speed and make a nudge forward of backwards as appropriate; or feel the ATHR do the same. You then follow up that sense with a quick scan of the N1% gauges.
Back to my earlier thought about the basic design philosophy of AB. This is not a FBW thing, but a whole a/c design thought. It may be true of EB and others as well. I wonder if the basic concept was to design an a/c that would fly approaches automatically, via ILS, LNAV/VNAV, RNAV, MLS etc. Program the approach in the FMC, engage the automatics and monitor. At minimums, no autoland, the human intervenes (gwad forbid) and attempts to bring a/c back to earth safely. Thus PF is really PM of the automatics. The non-handling pilot is then PM of the other PM/PF. The big difference between the two is one moves the gear & flaps, the other doesn't. One plants it on the ground or monitors the a/c do it and then one taxis the a/c. With 2 PM's I wonder how alert the PNF/PM is?
The certifying authorities need to ensure the human (let's call them pilots) could takeover if HAL goes awol to walkabout. That was seen by the designers as last resort, not the norm. Thus the depth of training to do such things is minimal, and the amount of 'on the line' practice is likewise. Many managements don't like pilots intervening and screwing up; so it's automatics to the max. Safer, cheaper, smoother.
All this might be great if operating from the major airport hubs. Perhaps the fully automatic a/c works great there. Take it out of its comfort zone and the basic design might not be quite so good. If you started with an a/c system design to operate in Africa, the Greek islands, Nepal, Indonesian islands would you have created the modern AB solution? Yet that is where they operate.
Note this is nothing about FBW; it is about the extent of automatics. The B737NG is very capable of flying, using automatics, from 400' on take off to a full autoland ILS or automatic NPA to MDA. It's more about the way there a/c is managed.
We hear many times from human factors professors that humans are not the best monitors of automatic systems, especially for hours on end. Airlines demand a high education from their plot recruits and then, due to a/c design, put them in a place they are ill-designed for. When airlines buy expensive a/c they buy the best design to suit the route demands. The same with the military. You try to balance and match your resources to maximise success of the operation. I wonder if modern automatic a/c, and the type of pilot in charge, is the best combination. Have modern high tech a/c been designed with human pilots in mind, or are they dream of lab' technocrats; designed because they can be? Has it all been necessary, and has it all been for the best? Will the future become better, or will it steam full ahead with the pilots out of the loop? Will they be given new toys and then enter the trained monkey system and be forced to adapt their natural skills to learn how to play with them? Square pegs, round holes. Are a/c best suited to those who should be managing them. If the technocrats win the argument and a/c continue to become more automatic, then the ground environment needs to keep pace: and, perhaps a different sort of human needs to be the PF/PM.
It seems to me that the technology is advancing at a much faster rate than any other link in the chain; because it can. It is all sold on cost benefit. The customers lap that up and so new a/c are designed in the R & D centres. Meanwhile the XAA's are so far removed from this that pilot training, checking, monitoring is still in the dark ages relative to the task involved. The certifiers are involved in that the a/c have to jump through time tested hoops. All the other links in the chain, including the pilots, as well. Is this the best way forward? Should thee be different hoops?
In some theatres a much more simple a/c is demanded, e.g. DH twin otter in Papua NG mountains. An automatic AB/Boeing type a/c would not work. That requires special pilot skills. B747 flying short hops in Japan is very different than a conventional long-haul B747 operation. Different pilot mind set. The same is true of the USA commuter market. Pilots fly in/out of tiny strips, but also JFK & Chicago. Different mind set and skills. Eventually, if it continues, all a/c may become FBW with associated automatic systems, but the pilot skills will still be very varied. Yet the basic training & checking will still be the same to obtain & maintain the licence the world over.
Perhaps it's time for a think tank or brains trust to sit down and have a good hard analysis about the world wide industry, its requirements and how best to create the ideal balance between the human and the task at hand. Even the a/c designers. Have a feedback loop from the customers and ask them if the suppliers are on the right track for the operators.
AB pilots have said that they need to increase their scan to include N1% gauges to monitor the ATHR system. To me this is increased work load at a time you might not find it the most convenient. On some a/c, with PFD and speed tape & speed trend vector display, as speed increases or reduces you can see the speed vector move. If the correct thrust adjustment is made you see the trend vector respond in the opposite sense. I'm not suggesting tunnel vision scan, but this important information is in your central scan. If using ATHR with moving levers you can 'feel' the a/c respond, then see its effect. If manual thrust then you apply the correction yourself and see the result. It's using more senses and having a solid feedback loop in your brain. IMHO you are more 'engaged' with the a/c. It is intuitive. If you have set a datum thrust for the phase of flight you can monitor speed and make a nudge forward of backwards as appropriate; or feel the ATHR do the same. You then follow up that sense with a quick scan of the N1% gauges.
Back to my earlier thought about the basic design philosophy of AB. This is not a FBW thing, but a whole a/c design thought. It may be true of EB and others as well. I wonder if the basic concept was to design an a/c that would fly approaches automatically, via ILS, LNAV/VNAV, RNAV, MLS etc. Program the approach in the FMC, engage the automatics and monitor. At minimums, no autoland, the human intervenes (gwad forbid) and attempts to bring a/c back to earth safely. Thus PF is really PM of the automatics. The non-handling pilot is then PM of the other PM/PF. The big difference between the two is one moves the gear & flaps, the other doesn't. One plants it on the ground or monitors the a/c do it and then one taxis the a/c. With 2 PM's I wonder how alert the PNF/PM is?
The certifying authorities need to ensure the human (let's call them pilots) could takeover if HAL goes awol to walkabout. That was seen by the designers as last resort, not the norm. Thus the depth of training to do such things is minimal, and the amount of 'on the line' practice is likewise. Many managements don't like pilots intervening and screwing up; so it's automatics to the max. Safer, cheaper, smoother.
All this might be great if operating from the major airport hubs. Perhaps the fully automatic a/c works great there. Take it out of its comfort zone and the basic design might not be quite so good. If you started with an a/c system design to operate in Africa, the Greek islands, Nepal, Indonesian islands would you have created the modern AB solution? Yet that is where they operate.
Note this is nothing about FBW; it is about the extent of automatics. The B737NG is very capable of flying, using automatics, from 400' on take off to a full autoland ILS or automatic NPA to MDA. It's more about the way there a/c is managed.
We hear many times from human factors professors that humans are not the best monitors of automatic systems, especially for hours on end. Airlines demand a high education from their plot recruits and then, due to a/c design, put them in a place they are ill-designed for. When airlines buy expensive a/c they buy the best design to suit the route demands. The same with the military. You try to balance and match your resources to maximise success of the operation. I wonder if modern automatic a/c, and the type of pilot in charge, is the best combination. Have modern high tech a/c been designed with human pilots in mind, or are they dream of lab' technocrats; designed because they can be? Has it all been necessary, and has it all been for the best? Will the future become better, or will it steam full ahead with the pilots out of the loop? Will they be given new toys and then enter the trained monkey system and be forced to adapt their natural skills to learn how to play with them? Square pegs, round holes. Are a/c best suited to those who should be managing them. If the technocrats win the argument and a/c continue to become more automatic, then the ground environment needs to keep pace: and, perhaps a different sort of human needs to be the PF/PM.
It seems to me that the technology is advancing at a much faster rate than any other link in the chain; because it can. It is all sold on cost benefit. The customers lap that up and so new a/c are designed in the R & D centres. Meanwhile the XAA's are so far removed from this that pilot training, checking, monitoring is still in the dark ages relative to the task involved. The certifiers are involved in that the a/c have to jump through time tested hoops. All the other links in the chain, including the pilots, as well. Is this the best way forward? Should thee be different hoops?
In some theatres a much more simple a/c is demanded, e.g. DH twin otter in Papua NG mountains. An automatic AB/Boeing type a/c would not work. That requires special pilot skills. B747 flying short hops in Japan is very different than a conventional long-haul B747 operation. Different pilot mind set. The same is true of the USA commuter market. Pilots fly in/out of tiny strips, but also JFK & Chicago. Different mind set and skills. Eventually, if it continues, all a/c may become FBW with associated automatic systems, but the pilot skills will still be very varied. Yet the basic training & checking will still be the same to obtain & maintain the licence the world over.
Perhaps it's time for a think tank or brains trust to sit down and have a good hard analysis about the world wide industry, its requirements and how best to create the ideal balance between the human and the task at hand. Even the a/c designers. Have a feedback loop from the customers and ask them if the suppliers are on the right track for the operators.
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Is an autopilot rudder channel available on B737? None I've flown. Every QRH I've seen B733/737/738 has instructed A/T off with SE ops. True, if an engine fails in CRZ the A/T will increase and try to maintain speed. I'm not sure how long it will remain connected. On takeoff it will disconnect during climb out.
Question to the AB pilots: when flying an approach with A/T engaged do you follow through on the T/L's? If not where do you have your inside hand? I suspect the B777 Asiana PF had both hands on the yoke; might be wrong.
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Chris Scott
Sorry I meant in manual flight. In a conventional aircraft the pressure felt on the yoke varies with thrust or speed change. That offers you another cue. That is what I meant.
Golden: the thrust/drag couple effect is also felt in the yoke. It is dampened in airbus. Basically it comes from the design of maintaining 1g when stick free.
Bird speed: It is airbus SOP to keep hands on thrust levers during approach. Latest being 1000ft. AGL. SFO pilot was perhaps not following SOPs even in Airbus.
Sorry I meant in manual flight. In a conventional aircraft the pressure felt on the yoke varies with thrust or speed change. That offers you another cue. That is what I meant.
Golden: the thrust/drag couple effect is also felt in the yoke. It is dampened in airbus. Basically it comes from the design of maintaining 1g when stick free.
Bird speed: It is airbus SOP to keep hands on thrust levers during approach. Latest being 1000ft. AGL. SFO pilot was perhaps not following SOPs even in Airbus.
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Originally Posted by birdspeed
Accidents where non-moving throttles may have been a factor-
Tam3054 at Sao Paolo,
Air Inter at Strasbourg
Tam3054 at Sao Paolo,
Air Inter at Strasbourg
Air Inter seemed to be a myriad of automation unfamiliarity, yes some design issues , questionable procedures (speed, no GPWS) , again where come the non moving TL in play?
Originally Posted by Winnerhofer
Asiana
Indeed, he forgot that there's no Alpha Floor on Boeings...
Indeed, he forgot that there's no Alpha Floor on Boeings...
BTW at 50' RA the Airbus switches to flare mode.
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He is joking about alpha floor. And they were 31kts below Vapp so if there was alpha floor it would have come before 50ft. In Bangalore crash it triggered at 135ft. but did not have the time to spool up and stop the descent.
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Originally Posted by vilas
He is joking about alpha floor.
Originally Posted by vilas
Bangalore crash it triggered at 135ft. but did not have the time to spool up ad stop the descent.
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kbrockman
They were coming off VOR approach converted to visual approach. But because one side FD was on FMGS went in OP DES with thrust at idle. Pilot tried to maintain visual 3 degree flight path with falling airspeed. Obviously they were not waiting for alpha floor but did not monitor speed assumed ATHR in speed mode.There were no warnings. Same as SFO but being an airbus alpha floor triggered and then they themselves triggered TOGA. In the ultimate analysis they lost there life because they did it five seconds too late.
They were coming off VOR approach converted to visual approach. But because one side FD was on FMGS went in OP DES with thrust at idle. Pilot tried to maintain visual 3 degree flight path with falling airspeed. Obviously they were not waiting for alpha floor but did not monitor speed assumed ATHR in speed mode.There were no warnings. Same as SFO but being an airbus alpha floor triggered and then they themselves triggered TOGA. In the ultimate analysis they lost there life because they did it five seconds too late.
RAT 5,
I like and agree with your analysis of the current automation problems in the aircraft industry as a whole.
You suggest, however, that a/c like the FBW Airbuses are designed to be operated into large hubs with autoland facilities. It needs to be said that the A320-series is well capable of doing anything that, say, the B737-200 can do, and do it better in most cases.
Non-precision approaches and/or visual circuits are easier to fly: with or without AP; with or without A/THR. Manual thrust is a delight on the Airbuses, partly because the FADEC gives such accurate responses to small thrust-lever movements. Used as designed, GS-Mini is a treat in gusty wx. FPA is, as you probably know, terrific for non-precision approaches: with or without the FD; with or without the AP. (In the airliner field, these were all innovations of the A320 in 1988, although the A310 had pioneered a basic FPA in 1983.)
Back to the thread topic! Quote from vilas, re the A320 accident at Bangalore in 1990:
"They were coming off VOR approach converted to visual approach. But because one side FD was on FMGS went in OP DES with thrust at idle. Pilot tried to maintain visual 3 degree flight path with falling airspeed. Obviously they were not waiting for alpha floor but did not monitor speed assumed ATHR in speed mode.There were no warnings. Same as SFO but being an airbus alpha floor triggered and then they themselves triggered TOGA."
Thank you for now reiterating my brief analysis in my post #14 yesterday (final paragraph), to which you took exception at the time. No need to apologise for changing your mind!
I like and agree with your analysis of the current automation problems in the aircraft industry as a whole.
You suggest, however, that a/c like the FBW Airbuses are designed to be operated into large hubs with autoland facilities. It needs to be said that the A320-series is well capable of doing anything that, say, the B737-200 can do, and do it better in most cases.
Non-precision approaches and/or visual circuits are easier to fly: with or without AP; with or without A/THR. Manual thrust is a delight on the Airbuses, partly because the FADEC gives such accurate responses to small thrust-lever movements. Used as designed, GS-Mini is a treat in gusty wx. FPA is, as you probably know, terrific for non-precision approaches: with or without the FD; with or without the AP. (In the airliner field, these were all innovations of the A320 in 1988, although the A310 had pioneered a basic FPA in 1983.)
Back to the thread topic! Quote from vilas, re the A320 accident at Bangalore in 1990:
"They were coming off VOR approach converted to visual approach. But because one side FD was on FMGS went in OP DES with thrust at idle. Pilot tried to maintain visual 3 degree flight path with falling airspeed. Obviously they were not waiting for alpha floor but did not monitor speed assumed ATHR in speed mode.There were no warnings. Same as SFO but being an airbus alpha floor triggered and then they themselves triggered TOGA."
Thank you for now reiterating my brief analysis in my post #14 yesterday (final paragraph), to which you took exception at the time. No need to apologise for changing your mind!
Although not a pilot, I've spent lots of time on the flight deck during flight tests - and observed countless simulator sessions - and the PF has always had one hand on the throttles during approach/landing. I've assumed that was SOP and pilots who flew Boeings were taught to do that.
Through the interpreter, I suggested that during any autopilot instrument approach it was wise to have one hand lightly on the throttles rather than both hands on the knees. My suggestion was curtly declined by the chief pilot who was PF and he continued with their own policy. Through the interpreter, I said that each throttle had a clutch motor and if a clutch motor happened to fail, the auto throttle would not move except by hand. By lightly resting one hand on the autothrottles during an approach, a split in the throttles could be quickly picked up.
Again this was ignored with an imperious wave of the chief pilot's hand. I found his attitude irritating especially as during the pre-flight briefing I specifically mentioned the wisdom of one hand resting lightly on the autothrottles during an instrument approach and particularly on final approach.
Accordingly, I re-positioned the simulator at 5000 ft on an automatic pilot/autothrottle descending DME arc leading into a coupled ILS approach. Both thrust levers were back at idle as expected for the clean descent at 210 knots. Via the instructor panel IOS, failure of the No.1 engine AT clutch motor was initiated while both throttles were at idle of 30% N1
Approaching 10 miles and coupled to the ILS, the pilot called for gear down, and various flap selections as the speed bled back at each flap selection until the automatic throttles started to increase thrust towards landing configuration thrust settings. Naturally, the No 1 thrust lever remained at idle as its clutch motor was inoperative. All the time both pilots had their hands on their knees apart from configuration selections by the co-pilot
At five miles in IMC on final, No. 2 engine was around 75%N1 to make up for the lack of thrust from the closed No.1 throttle which indicated 30% N1.. The autopilot was struggling to track the ILS under significant asymmetric power and the control wheel was now 45 degrees off centre. Rudders were central. Neither pilot said anything and did nothing but stolidly gaze at the displaced control wheel and presumably at the split in the thrust levers.
I was amazed, as I had never witnessed anything like this before. Eventually I leaned over to the interpreter who was sitting in the jump seat and asked her to tell the captain about the split in throttles with No.1 at idle and No.2 at 75%N1. Still with both hands on his knees the captain shouted at his co-pilot in Chinese that No.1 engine had failed and called for the engine failure and shut down checklist from the QRH. There was of course nothing wrong with the engine and the throttle could be moved manually if desired.
As the co-pilot dived to locate the QRH from somewhere on the cockpit floor (he never queried the captain's actions probably due to cultural mores), the autopilot disengaged itself under excessive control deflection, and the 737 started to roll rapidly left under the influence of asymmetric thrust. The captain still kept both of his hands on his knees making no attempt to stop the ever-increasing yaw and roll. He did however shout louder at the co-pilot presumably urging him to get to the right page of the QRH. I saw the co-pilot flipping the pages of the QRH as fast as a bank teller counting notes and I fully expected him to lick his fingers to get a faster flick.
I watched in great interest knowing that no one would ever believe my story at what I was seeing. By now the simulator ADI was showing 30 degrees nose down and 80 degrees angle of bank with a massive rate of descent. At no stage did the captain take his hands off his knees and at no stage did the co-pilot look up from flicking then pages of his QRH. All this below 1000 ft on final and in IMC.
All the captain had to do early in this drama was to use both throttles to get equal power and full aileron to level the wings and go-around. The GPWS was going mad and to avoid the inevitable loss of face that would have occurred with the chief pilot crashing the aircraft, I froze the simulator when the crash was inevitable.
We all went for coffee in silence. There was no point in labouring the point while culture reigned supreme. I didn't operate in the simulator with that crew again so I have no idea if they changed the company policy of hands on the knees on instrument approaches...
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Flew both of them, but I have many more hours on "not moving"..
I personally don't like those who are trying to convince the others that one system is better than the other one, these are just opinions.
That being said, on Airbus you are supposed to keep your hand on the thrust levers as well as on Boeing and you can "help" the autothrust in any moment. If you feel you need to.
I personally do not see any advantage in having my hand rallying forward and back all the time to follow the autothrust.
Airbus and Boeing pilots make the same mistakes, they just do not crosscheck properly their instruments and many times they keep their hands on the armrests.
My opinion: there is no safer system here, and I prefer the not moving.
I personally don't like those who are trying to convince the others that one system is better than the other one, these are just opinions.
That being said, on Airbus you are supposed to keep your hand on the thrust levers as well as on Boeing and you can "help" the autothrust in any moment. If you feel you need to.
I personally do not see any advantage in having my hand rallying forward and back all the time to follow the autothrust.
Airbus and Boeing pilots make the same mistakes, they just do not crosscheck properly their instruments and many times they keep their hands on the armrests.
My opinion: there is no safer system here, and I prefer the not moving.
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Centaurus: I sometimes wonder why people make an easy job difficult.
I guess it depends on your SOPs. As part of our general SOPs for all fleets we have to "guard" (have the hand on them) the controls below FL150 with the autopilot engaged.
What's it got to do with SOP's? Airmanship is an SOP, IMHO. Covering the controls on approach is surely an airmanship item. I've flown with the trained monkey brigade and it is very disturbing. "it's to an SOP, so I don't do it." "Where's that written?" For gawd's sake!
I guess it depends on your SOPs. As part of our general SOPs for all fleets we have to "guard" (have the hand on them) the controls below FL150 with the autopilot engaged.
What's it got to do with SOP's? Airmanship is an SOP, IMHO. Covering the controls on approach is surely an airmanship item. I've flown with the trained monkey brigade and it is very disturbing. "it's to an SOP, so I don't do it." "Where's that written?" For gawd's sake!
That being said, on Airbus you are supposed to keep your hand on the thrust levers as well as on Boeing and you can "help" the autothrust in any moment
This mostly happens when selecting TOGA and misguided PM's urge the throttles forward with their hand behind the levers as a backing up policy when there is no need since they won't slip back because of the internal throttle friction system.
Like those pilots that "follow through" on the flight controls while the other pilot is PF, there is nothing more annoying for the pilot to be smoothly opening the throttles manually and feel the other eager beaver pushing them from behind. In fact, something goes wrong and the PF suddenly whips the throttles to idle to abort and the PM still has his hand behind the levers as a following through habit, severe hand damage has happened when the PM's his hand is jammed between the throttle and the top of the start levers because he can't remove it in time. . I have seen it happen in the simulator and it is very very painful.