Emirates B777 gear collapse @ DXB?
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Stator Vane: 100%. The FMA tells you what the AFDS doing via FD or autopilot. The basic performance instruments tell you what the a/c is doing. Which is more important? Today's trained monkeys have not been taught the basics of a/c performance and aerodynamic performance and interpreting a scan. It is not their fault.
If you have the automatics on, the FMA is only way you know what they are doing. This includes the thrust. If you don't want to read the FMA that's fine, but make sure the automatic stuff is turned off first.
Is there any indication that the number of GAs have increased since the introduction of RAAS as suggested might happen in #1525 http://www.pprune.org/rumours-news/5...ml#post9507678.
Would any increase in GAs influence management's balance of safety benefit vs operating cost.
Has RAAS been overly promoted by Boeing to offset Airbus' ROPS, which is a true predictive system when airborne, and provides positive advice on the ground.
don, do read the ASAGA report #1560
Would any increase in GAs influence management's balance of safety benefit vs operating cost.
Has RAAS been overly promoted by Boeing to offset Airbus' ROPS, which is a true predictive system when airborne, and provides positive advice on the ground.
don, do read the ASAGA report #1560
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I don't know if things have improved or not, but the RAAS was somewhat inaccurate when I was using it. It would often warn of approaching a runway only after you were past the holding point & actually on the runway. Not much help then. If it is still that inaccurate, perhaps the warning this flight crew received was not entirely appropriate.
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As part of your daily departure briefing ensure that you include the instruction to utterly ignore any callout from the RAAS except for "on taxiway" and "altimeter setting".
If this causes a summons for tea and biscuits enjoy them to the utmost as a professional aviator, positioned high above the drones who have summoned you.
If this causes a summons for tea and biscuits enjoy them to the utmost as a professional aviator, positioned high above the drones who have summoned you.
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That is why the ground based systems will directly provide the wind data to the FMS, that way, the system can compare and validate what the winds are for the system to use.
There are already several systems that do this though the IFE bandwidth.
There are already several systems that do this though the IFE bandwidth.
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One would think that as RAAS becomes more common, even in B737NG a/c, the training of manoeuvres in response to the cautions will need to be reviewed carefully. I have no knowledge of the system, but if it can generate a "long landing' caution, even after touchdown, and if the SOP is to reject the landing, then this manoeuvre needs to be trained, surely. In today's environment trained often = an SOP. Currently the rejected landing is an FCTM manoeuvre. Many airlines have a single GA SOP. However, there are multitude of reasons to make a GA where a single SOP is not appropriate.
1. ATC Go Round when above MAA. This s not really a GA but an abandoned approach. If in APP mode this would cause many crews much confusion how to achieve it wth automatics; and it may well be that the best method is to disconnect then reconnect in basic mode and reselect what is necessary. I'm sure it is untrained in TR's. Perhaps some recurrency might include it, but I never saw it. System knowledge was the key.
2. GA anywhere between MAA & DA. You might be in APP mode or only LOC. Again a moment of pause then act. No rush.
3. GA at DA. Straight forward, often rushed, and the SOP kicks in. Trained.
4. Wave Off below DA. SOP GA. You may touchdown, but continue. Trained.
5. Heavy bounced landing. GA, but be careful and gentle as you are VERY close to the ground. Not trained. SOP might work, but wth some finesse. What guidance is given, if any?
6. Rejected landing after touchdown. GA SOP not appropriate. Not trained (uncommon)
Now if RAAS is fitted it could give a warning in Nos. 5 & 6. To certify crews to fly with RAAS is there a training program to give crews experience of the difference in GA technique to the standard, or is it just a self-study technical toy that has been added with written instructions of what to do but not how?
What are your experiences of training to use this system for airborne caution/warnings?
1. ATC Go Round when above MAA. This s not really a GA but an abandoned approach. If in APP mode this would cause many crews much confusion how to achieve it wth automatics; and it may well be that the best method is to disconnect then reconnect in basic mode and reselect what is necessary. I'm sure it is untrained in TR's. Perhaps some recurrency might include it, but I never saw it. System knowledge was the key.
2. GA anywhere between MAA & DA. You might be in APP mode or only LOC. Again a moment of pause then act. No rush.
3. GA at DA. Straight forward, often rushed, and the SOP kicks in. Trained.
4. Wave Off below DA. SOP GA. You may touchdown, but continue. Trained.
5. Heavy bounced landing. GA, but be careful and gentle as you are VERY close to the ground. Not trained. SOP might work, but wth some finesse. What guidance is given, if any?
6. Rejected landing after touchdown. GA SOP not appropriate. Not trained (uncommon)
Now if RAAS is fitted it could give a warning in Nos. 5 & 6. To certify crews to fly with RAAS is there a training program to give crews experience of the difference in GA technique to the standard, or is it just a self-study technical toy that has been added with written instructions of what to do but not how?
What are your experiences of training to use this system for airborne caution/warnings?
RAT, RAAS should only give a Long Landing alert in the air; see http://www.pprune.org/tech-log/58438...ml#post9507540
The concern, the effect of an apparent alert on the ground, which may apply in this accident (and probably is what you implied) is that a 'valid' RAAS alert could be given in the air, and where SOPs demand a GA it requires a late non-standard version of the GA procedure, however, by the time (short time) TOGA is selected the automatic TOGA function is no longer available as the aircraft is effectively on the ground (<2ft) which requires a completely different rejected landing procedure. (#1525) Confusing, yes ?
The position accuracy comments are interesting; presumable such errors are function of the GPS performance and/or system input (see previous comments on GPS Nav input vs internal GPS from EGPWS).
RAAS is a very good safety concept, but one wonders if it has been pushed a bit too far for landing performance due to system accuracy, aircraft installation/FGS interface, and how it is used (choice of SOP).
The concern, the effect of an apparent alert on the ground, which may apply in this accident (and probably is what you implied) is that a 'valid' RAAS alert could be given in the air, and where SOPs demand a GA it requires a late non-standard version of the GA procedure, however, by the time (short time) TOGA is selected the automatic TOGA function is no longer available as the aircraft is effectively on the ground (<2ft) which requires a completely different rejected landing procedure. (#1525) Confusing, yes ?
The position accuracy comments are interesting; presumable such errors are function of the GPS performance and/or system input (see previous comments on GPS Nav input vs internal GPS from EGPWS).
RAAS is a very good safety concept, but one wonders if it has been pushed a bit too far for landing performance due to system accuracy, aircraft installation/FGS interface, and how it is used (choice of SOP).
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RAAS should only give a Long Landing alert in the air
my red.
The new Long Landing and airborne only Distance Remaining
alerts are generated when the following conditions are met:
• Aircraft is within 100 feet AGL, over a customer specified
distance from the runway end;
• Aircraft is airborne above 5 feet AGL, or weight on
wheels is false
alerts are generated when the following conditions are met:
• Aircraft is within 100 feet AGL, over a customer specified
distance from the runway end;
• Aircraft is airborne above 5 feet AGL, or weight on
wheels is false
Preliminary report, factual information.
0837:17 Right main touchdown
0837:19 RAAS "Long Landing Long Landing"
0837:20 Left main Gear touchdown
0837:23 Aircraft airborne again.
The next question is when is TOGA disabled? Are both WoW inputs required to inhibit it, or just one? Was TOGA pressed & when in the timeline? Is there a small window of opportunity for RAAS still being enabled, whilst TOGA is simultaneously inhibited?
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"The preliminary report on the Aug. 3 crash landing of an Emirates Airline Boeing 777-300 at Dubai International Airport stated that the aircraft attempted a go-around after initially touching down briefly.
All 300 passengers and crew escaped as the aircraft burst into flames, but an airport firefighter was killed when the aircraft’s center fuel tank exploded as he fought the blaze after the aircraft came to a rest. The aircraft was destroyed, marking the first hull loss for Emirates.
The preliminary report, published by the United Arab Emirates General Civil Aviation Authority, is purely factual and does not attempt any analysis of the reasons for the crash. That will follow when the final report is published.
The preliminary report stated the aircraft was reaching the end of its flight from Trivandrum International Airport in southern India and was on approach to Dubai’s runway 12L. The captain was the pilot flying (PF) and the co-pilot was the pilot monitoring (PM).
As the flight neared Dubai, it received a warning from the automatic terminal information service of wind shear conditions affecting all runways.
As the aircraft descended through 1,100 ft. at 152 kts. indicated airspeed (IAS), the headwind of 8 kts. changed to a tailwind. The autopilot was disengaged at approximately 920 ft. and the approach continued with autothrottle connected. As the aircraft descended through 700 ft., the tailwind gradually increased to 16 kts.
The PF began to flare the aircraft—the landing step that follows final approach—at 35 ft. and 159 kts. IAS. The autothrottle transitioned to idle and both thrust levers moved towards the idle position. At 160 kts. IAS— 5 ft. above the runway and five seconds before touchdown—the wind direction again started to change to a headwind.
The right main landing gear touched down approximately 1,100 meters from the runway 12L threshold at 162 kts. IAS, followed three seconds later by the left main landing gear. The nose landing gear remained in the air.
Two seconds later, the aircraft’s runway awareness advisory system (RAAS) triggered a “long landing, long landing” warning and, four seconds later, the aircraft became airborne again in an attempt to go around.
A few seconds later the undercarriage began to retract. The aircraft reached a maximum height of approximately 85 ft. at 134 kts. IAS, with the landing gear still retracting, when it began to drop back onto the runway.
According to the report, both pilots recalled seeing the IAS decreasing and the co-pilot called out “check speed.” Three seconds before impact with the runway, both thrust levers were moved from the idle position to full forward.
One second before impact, both engines started to respond, but the aircraft’s aft fuselage hit the runway, with a nose-up pitch angle of 9.5 degrees, and at a rate of descent of 900 ft. per minute. The engine nacelles then hit the runway.
As the aircraft slid along the runway, the No. 2 engine-pylon assembly separated from the right hand wing and an intense fuel fire began at the engine-pylon wing attachment area. Subsequently, another fire began on the underside of the No. 1 engine.
The PF transmitted a Mayday call and advised that the aircraft was being evacuated. The first airport fire service vehicle arrived within one minute of the aircraft coming to a stop and began spraying foam, with other vehicles arriving shortly afterward.
Apart from the firefighter who died, 21 passengers, one pilot and one cabin crew member sustained minor injuries. Another cabin crew member was more seriously injured and hospitalized for five days with smoke inhalation."
UAE: Emirates 777 touched down long, then attempted go-around | Safety content from ATWOnline
All 300 passengers and crew escaped as the aircraft burst into flames, but an airport firefighter was killed when the aircraft’s center fuel tank exploded as he fought the blaze after the aircraft came to a rest. The aircraft was destroyed, marking the first hull loss for Emirates.
The preliminary report, published by the United Arab Emirates General Civil Aviation Authority, is purely factual and does not attempt any analysis of the reasons for the crash. That will follow when the final report is published.
The preliminary report stated the aircraft was reaching the end of its flight from Trivandrum International Airport in southern India and was on approach to Dubai’s runway 12L. The captain was the pilot flying (PF) and the co-pilot was the pilot monitoring (PM).
As the flight neared Dubai, it received a warning from the automatic terminal information service of wind shear conditions affecting all runways.
As the aircraft descended through 1,100 ft. at 152 kts. indicated airspeed (IAS), the headwind of 8 kts. changed to a tailwind. The autopilot was disengaged at approximately 920 ft. and the approach continued with autothrottle connected. As the aircraft descended through 700 ft., the tailwind gradually increased to 16 kts.
The PF began to flare the aircraft—the landing step that follows final approach—at 35 ft. and 159 kts. IAS. The autothrottle transitioned to idle and both thrust levers moved towards the idle position. At 160 kts. IAS— 5 ft. above the runway and five seconds before touchdown—the wind direction again started to change to a headwind.
The right main landing gear touched down approximately 1,100 meters from the runway 12L threshold at 162 kts. IAS, followed three seconds later by the left main landing gear. The nose landing gear remained in the air.
Two seconds later, the aircraft’s runway awareness advisory system (RAAS) triggered a “long landing, long landing” warning and, four seconds later, the aircraft became airborne again in an attempt to go around.
A few seconds later the undercarriage began to retract. The aircraft reached a maximum height of approximately 85 ft. at 134 kts. IAS, with the landing gear still retracting, when it began to drop back onto the runway.
According to the report, both pilots recalled seeing the IAS decreasing and the co-pilot called out “check speed.” Three seconds before impact with the runway, both thrust levers were moved from the idle position to full forward.
One second before impact, both engines started to respond, but the aircraft’s aft fuselage hit the runway, with a nose-up pitch angle of 9.5 degrees, and at a rate of descent of 900 ft. per minute. The engine nacelles then hit the runway.
As the aircraft slid along the runway, the No. 2 engine-pylon assembly separated from the right hand wing and an intense fuel fire began at the engine-pylon wing attachment area. Subsequently, another fire began on the underside of the No. 1 engine.
The PF transmitted a Mayday call and advised that the aircraft was being evacuated. The first airport fire service vehicle arrived within one minute of the aircraft coming to a stop and began spraying foam, with other vehicles arriving shortly afterward.
Apart from the firefighter who died, 21 passengers, one pilot and one cabin crew member sustained minor injuries. Another cabin crew member was more seriously injured and hospitalized for five days with smoke inhalation."
UAE: Emirates 777 touched down long, then attempted go-around | Safety content from ATWOnline
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Many airlines have a single GA SOP. However, there are multitude of reasons to make a GA where a single SOP is not appropriate.
CT, an intriguing analysis (#1573).
The logic given is according to Honeywell, but the precise integration and configuration for the 777 is not known.
It would be unusual to use a single switch, the RAAS description of 'WoW' is more likely to be a generic input term. The aircraft output would have be chosen by Boeing, which probably involves at least both main wheels. Some aircraft use a 'two out of three' logic to provide additional integrity for WoW or specific systems' selection.
It is even feasible that the 777 RAAS installation chose a logic which provided RAAS alerts until all wheels are on the ground, and perhaps with pilot reaction time, represents the last chance of a rejected landing. I think that is is too much to suppose and it would further complicate the contradictions and confusion with SOPs and TOGA.
The primary inhibition on the RAAS alert appears to be 'less than 5ft', but this is not necessarily supported by the FDR. However, without knowledge of the FDR update rate for an assumed 'low priority' advisory RAAS parameter (~4 sec?) there is no certainty.
Also, it would be unusual to consider WoW as a backup for loss RA when the RA is required previously to enable the long landing alert (<100ft); I suspect that this is associated with other parts of RAAS.
The details of 777 TOGA inhibit are unclear; the FCOM suggests WoW (but which aircraft logic?), yet there is technical opinion that it occurs at <2 ft RA (and what's the back up system for a failed RA?).
This whole issue highlights the importance of management requiring a thorough understanding of 'add-on' systems and the host aircraft. And particularly the interface and interactions before choosing an operating procedure (N.B Honeywell does not require a GA).
The alerting system and aircraft manufacturer also have roles in this area, as should the approving regulator. Whilst independently each system / aircraft function meets the certification requirements, together, the previously assumed risks (certification basis) in new 'improbable', yet relevant situations can be very significant.
The logic given is according to Honeywell, but the precise integration and configuration for the 777 is not known.
It would be unusual to use a single switch, the RAAS description of 'WoW' is more likely to be a generic input term. The aircraft output would have be chosen by Boeing, which probably involves at least both main wheels. Some aircraft use a 'two out of three' logic to provide additional integrity for WoW or specific systems' selection.
It is even feasible that the 777 RAAS installation chose a logic which provided RAAS alerts until all wheels are on the ground, and perhaps with pilot reaction time, represents the last chance of a rejected landing. I think that is is too much to suppose and it would further complicate the contradictions and confusion with SOPs and TOGA.
The primary inhibition on the RAAS alert appears to be 'less than 5ft', but this is not necessarily supported by the FDR. However, without knowledge of the FDR update rate for an assumed 'low priority' advisory RAAS parameter (~4 sec?) there is no certainty.
Also, it would be unusual to consider WoW as a backup for loss RA when the RA is required previously to enable the long landing alert (<100ft); I suspect that this is associated with other parts of RAAS.
The details of 777 TOGA inhibit are unclear; the FCOM suggests WoW (but which aircraft logic?), yet there is technical opinion that it occurs at <2 ft RA (and what's the back up system for a failed RA?).
This whole issue highlights the importance of management requiring a thorough understanding of 'add-on' systems and the host aircraft. And particularly the interface and interactions before choosing an operating procedure (N.B Honeywell does not require a GA).
The alerting system and aircraft manufacturer also have roles in this area, as should the approving regulator. Whilst independently each system / aircraft function meets the certification requirements, together, the previously assumed risks (certification basis) in new 'improbable', yet relevant situations can be very significant.
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I agree that the logic and inputs related to RAAS alerts need to be looked at hard to avoid unnecessary Go Arounds. But no matter how well the RAAS functions, the fact remains that a Go Around attempt should never result in gear up ground contact. Had the flight crew verified power lever position and/or manually moved the power levers rather than relying completely on the automatics, the go around would have been successful and this disaster averted. Particularly unsettling to me is that the TOGA switches on a B777 are right in front of the tops of the power levers (see photo below). How the pilot can press the TOGA switches and not feel the levers stay stationary and not advancing is beyond me. Clearly he was trained very differently than I. To me, the main lesson learned here is that flight crews need to be trained how to aviate without resort to automatics, and taught to always verify what the automatics are doing, ESPECIALLY when they are in proximity to the ground and/or at low airspeeds. And on Boeing products I believe they should be taught to verify what the automatics are doing tactilely (feel is a very instinctive feedback) because on Boeing products (unlike Airbus products) the flight/thrust controls always move to reflect what the automatics are doing. (NOTE: I'm NOT saying the "Boeing way" is "better". I'm just saying that since tactile feedback is available on Boeing aircraft, flight crew should be trained to make use of that tactile feedback.)
Last edited by KenV; 16th Sep 2016 at 15:33.
KenV, " should never result; a common misconception, where IMHO the reasons for this disbelief of human behaviour are explained in the interesting ASAGA report.
"The time pressure associated with limited human cognitive abilities - and therefore of crews - is the major problem in ASAGA. The crew must perform a number of actions and cross-check them in a short time. The induced cognitive overload may prevent the detection of deviations both by the PF, who is mainly concentrated on the PFD, and by the PM, who undertakes a set of tasks that divert his attention. Thus, a deviation, even in an important parameter or in the flight path, may not be detected by the crew."
And a quote from some wit, but without comment or rflection on your views in any way:-
All accidents are preventable... with the benefit of hindsight...or
All accidents are preventable... in theory...or
All accidents are preventable... given unlimited knowledge, resources, perfect prediction (and quite some luck).
All of which, regrettably makes it a rather useless statement in the everyday job.
And besides, do we really want to prevent absolutely everything? ... Really??
“systems work as designed, just not how the designer intended.”
"The time pressure associated with limited human cognitive abilities - and therefore of crews - is the major problem in ASAGA. The crew must perform a number of actions and cross-check them in a short time. The induced cognitive overload may prevent the detection of deviations both by the PF, who is mainly concentrated on the PFD, and by the PM, who undertakes a set of tasks that divert his attention. Thus, a deviation, even in an important parameter or in the flight path, may not be detected by the crew."
And a quote from some wit, but without comment or rflection on your views in any way:-
All accidents are preventable... with the benefit of hindsight...or
All accidents are preventable... in theory...or
All accidents are preventable... given unlimited knowledge, resources, perfect prediction (and quite some luck).
All of which, regrettably makes it a rather useless statement in the everyday job.
And besides, do we really want to prevent absolutely everything? ... Really??
“systems work as designed, just not how the designer intended.”
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KenV, " should never result; a common misconception, where IMHO the reasons for this disbelief of human behaviour are explained in the interesting ASAGA report.
"The time pressure associated with limited human cognitive abilities - and therefore of crews - is the major problem in ASAGA. The crew must perform a number of actions and cross-check them in a short time. The induced cognitive overload may prevent the detection of deviations both by the PF, who is mainly concentrated on the PFD, and by the PM, who undertakes a set of tasks that divert his attention. Thus, a deviation, even in an important parameter or in the flight path, may not be detected by the crew."
"The time pressure associated with limited human cognitive abilities - and therefore of crews - is the major problem in ASAGA. The crew must perform a number of actions and cross-check them in a short time. The induced cognitive overload may prevent the detection of deviations both by the PF, who is mainly concentrated on the PFD, and by the PM, who undertakes a set of tasks that divert his attention. Thus, a deviation, even in an important parameter or in the flight path, may not be detected by the crew."
And a quote from some wit, but without comment or rflection on your views in any way:-
All accidents are preventable... with the benefit of hindsight...or
All accidents are preventable... in theory...or
All accidents are preventable... given unlimited knowledge, resources, perfect prediction (and quite some luck).
All of which, regrettably makes it a rather useless statement in the everyday job.
And besides, do we really want to prevent absolutely everything? ... Really??
All accidents are preventable... with the benefit of hindsight...or
All accidents are preventable... in theory...or
All accidents are preventable... given unlimited knowledge, resources, perfect prediction (and quite some luck).
All of which, regrettably makes it a rather useless statement in the everyday job.
And besides, do we really want to prevent absolutely everything? ... Really??
Can we prevent pilots from failing to add thrust during a go around? Absolutely yes. Please allow me to alter your question just slightly: "Do we really want to prevent"... pilots from failing to add thrust during a Go Around? Yes!!! We absolutely want to do that!!!! While there are countless things we cannot foresee and thus cannot prevent, pilots failing to add thrust during a go around is NOT one of them!
To put what KenV is saying a bit differently:
'On Boeings, the flight/thrust controls move to reflect what the automatics are doing'. Wither or not that's better than the AB way is not the point - the point is that Boeing does that on purpose to provide the pilots tactile feedback of what the automatics are doing (and it the case of the flight controls, what the other pilot is doing). Pilots training and SOPs should be designed to take advantage of that feedback - to pound it into the pilots to verify - via that designed in tactile feedback - that the automatics (or the other pilot) are doing what they want them to.
'On Boeings, the flight/thrust controls move to reflect what the automatics are doing'. Wither or not that's better than the AB way is not the point - the point is that Boeing does that on purpose to provide the pilots tactile feedback of what the automatics are doing (and it the case of the flight controls, what the other pilot is doing). Pilots training and SOPs should be designed to take advantage of that feedback - to pound it into the pilots to verify - via that designed in tactile feedback - that the automatics (or the other pilot) are doing what they want them to.
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Interesting point and it caused me to reflect on something most of us do by intuition; car driving. This is not expressing an opinion, but opening a human performance discussion.
Steering: if we want to turn gently we deflect, and HOLD the deflection to complete the turn. If we wish to alter the radius we alter the deflection and receive a change in force feedback. In hydraulic controlled a/c we deflect ailerons and when the BA is reached we centralise; AB perhaps more so than Boeing. At least we move the relevant control. Changes in forces are less than cars.
With changing thrust in a car we deflect the accelerator pedal, more or less and keep it deflected. Auto-Thrust in Boeing yes, in AB no. With braking we deflect the pedal and the stronger the braking the harder the deflection and force feedback. In all these actions, car or a/c we have feedback to our tactile sense and follow it up with visual senses and g forces. The car doesn't do pitch, but in the a/c we deflect the control and centralise, AB, or manually trim out the force, old Boeing.
The point being, in a car, if we want to do something we deflect a control and feel it move and receive various forms of feedback. Even in CRZ Control we can feel the accelerator move automatically with our foot and see the RPM change.
I'm not an FBW pilot, but I wonder if we've removed too much of the instinctive tactile feedback we receive in an a/c and make it so different to something we do every day instinctively without conscious effort. Is removing the power pitch couple and improvement in letting us know what the a/c is doing?
The other argument is that the a/c is designed to be flown more via automatics than manually. Once airborne, and until flare, it can be purely a monitoring role: i.e. the feedback is only visual with some g thrown in. Is this instinctive? In other words would we be better off in some phases of flight being more manual and less automatic? Being trained about the automatic systems & understanding the automatic systems in a stressless class room is one thing, but under stress, or startle, would instinctive reactions be safer? This question about AT over dependancy, even in manual flight is a case in point. If it is manual thrust, with pitch couple (feedback effect) there is no doubt what is necessary. Does this not remove confusion; because it seems to be confusion about an automatic system that has caused various crashes. Remove the doubt.
I've only flown an AB sim for 1hr. The role control was not instinctive; i.e. the nudge/centre/nudge/centre. It needed strong concentration on PFD. From some I've spoken to it's not so easy, in the early days, in strong gusty X-wnds as a conventional column e.g. B757/767/737. I can not comment on B777. The AB pilots will be able to inform us much better, and B777 as well. I hear it can be trained and you can 'get used to it', even the non-moving TL's, but from a human factors perspective is the reduced tactile feedback and reduced 'instinctive behaviour' an improvement & safer for manual flight?
I know the techies are trying to persuade us about automatic cars. I am sceptical . They might work on motorways specially designed for nose to tail max flow at constant speed with no lane changes = 4 wheel trains in convoy; but in towns & cities? Hm? Our instincts will still be needed.
I'm sure there will be strong opinions from the old & new, standard hydraulic & FBW, AB & Boeing. I've read that people love one or the other, or have no problem with either. My query is about it being instinctive or not. Do we as pilots not rely on instincts subconsciously? If, during critical phases on manual flight, everything has to be scanned, monitored, interpreted e.g. FMA to know what is going on, is there not a tiny delay in digesting the information and deciding on an action, or even a possibility of confusion and even further delay on action? I once jump seated during live base training of a DC8 captain trying to fly circuits in B757. The SOP was to use FD's and call for MCP changes. He was all over the sky and the TRE was ready to bin him as a non-pilot. I suggest switching off the FD's so he didn't have to think, speak, follow. He went back to basics & instincts in silence and flew it on rails.
I know there are many who believe we are here & now in 21st century not in steam driven jets of 80's. True; but does that mean that we are operating the new technology in the best manner, or that the new technology, just because it is hi-tech, is automatically better in every respect? We haven't changed the human very much but we sure have changed what they have to interact with by huge amounts. Do we have the best combination? Have we moved too far & too fast?
Steering: if we want to turn gently we deflect, and HOLD the deflection to complete the turn. If we wish to alter the radius we alter the deflection and receive a change in force feedback. In hydraulic controlled a/c we deflect ailerons and when the BA is reached we centralise; AB perhaps more so than Boeing. At least we move the relevant control. Changes in forces are less than cars.
With changing thrust in a car we deflect the accelerator pedal, more or less and keep it deflected. Auto-Thrust in Boeing yes, in AB no. With braking we deflect the pedal and the stronger the braking the harder the deflection and force feedback. In all these actions, car or a/c we have feedback to our tactile sense and follow it up with visual senses and g forces. The car doesn't do pitch, but in the a/c we deflect the control and centralise, AB, or manually trim out the force, old Boeing.
The point being, in a car, if we want to do something we deflect a control and feel it move and receive various forms of feedback. Even in CRZ Control we can feel the accelerator move automatically with our foot and see the RPM change.
I'm not an FBW pilot, but I wonder if we've removed too much of the instinctive tactile feedback we receive in an a/c and make it so different to something we do every day instinctively without conscious effort. Is removing the power pitch couple and improvement in letting us know what the a/c is doing?
The other argument is that the a/c is designed to be flown more via automatics than manually. Once airborne, and until flare, it can be purely a monitoring role: i.e. the feedback is only visual with some g thrown in. Is this instinctive? In other words would we be better off in some phases of flight being more manual and less automatic? Being trained about the automatic systems & understanding the automatic systems in a stressless class room is one thing, but under stress, or startle, would instinctive reactions be safer? This question about AT over dependancy, even in manual flight is a case in point. If it is manual thrust, with pitch couple (feedback effect) there is no doubt what is necessary. Does this not remove confusion; because it seems to be confusion about an automatic system that has caused various crashes. Remove the doubt.
I've only flown an AB sim for 1hr. The role control was not instinctive; i.e. the nudge/centre/nudge/centre. It needed strong concentration on PFD. From some I've spoken to it's not so easy, in the early days, in strong gusty X-wnds as a conventional column e.g. B757/767/737. I can not comment on B777. The AB pilots will be able to inform us much better, and B777 as well. I hear it can be trained and you can 'get used to it', even the non-moving TL's, but from a human factors perspective is the reduced tactile feedback and reduced 'instinctive behaviour' an improvement & safer for manual flight?
I know the techies are trying to persuade us about automatic cars. I am sceptical . They might work on motorways specially designed for nose to tail max flow at constant speed with no lane changes = 4 wheel trains in convoy; but in towns & cities? Hm? Our instincts will still be needed.
I'm sure there will be strong opinions from the old & new, standard hydraulic & FBW, AB & Boeing. I've read that people love one or the other, or have no problem with either. My query is about it being instinctive or not. Do we as pilots not rely on instincts subconsciously? If, during critical phases on manual flight, everything has to be scanned, monitored, interpreted e.g. FMA to know what is going on, is there not a tiny delay in digesting the information and deciding on an action, or even a possibility of confusion and even further delay on action? I once jump seated during live base training of a DC8 captain trying to fly circuits in B757. The SOP was to use FD's and call for MCP changes. He was all over the sky and the TRE was ready to bin him as a non-pilot. I suggest switching off the FD's so he didn't have to think, speak, follow. He went back to basics & instincts in silence and flew it on rails.
I know there are many who believe we are here & now in 21st century not in steam driven jets of 80's. True; but does that mean that we are operating the new technology in the best manner, or that the new technology, just because it is hi-tech, is automatically better in every respect? We haven't changed the human very much but we sure have changed what they have to interact with by huge amounts. Do we have the best combination? Have we moved too far & too fast?
KenV, let's take a step back; remove the barbs from my previous post.
By focusing on just one item it is very difficult to avoid ending up blaming the pilot. The greater safety benefit is to explore why activities were not completed, or what factors might have contributed to an oversight, with the objective to aid crews alleviate the risks in these situations.
What has been published and discussed so far indicates that this was an 'unforeseen' accident; not an extreme unforeseeable event, but something which fell outside of the classic approach to safety. It appears to have emerged from a combination of factors involving many aspects of operation; these situations require a different approach to investigation and safety improvement.
For example, compare this incident with many successful GAs, where crew actions were correct, or if with deviation, were detected and corrected in time. Perhaps this accident involved an excessive variation in actions or corrective action took longer; the latter is more likely.
By considering the human as an asset in maintaining safety, as indicated by the successes of normal operation, then an output of accident investigation should identify aspects which increased the difficulty for the crew to act normally, and with this consider alleviation.
A major theme from the ASAGA report considered task saturation, workload, and time, against the backdrop of surprise.
Those aspect already discussed about systems integration, SOPs, and operational assumptions about new systems, should be reconsidered to reduce surprise, workload, etc, to effect change.
I refrain from choosing one item; emergent accidents require safety changes which involve many apparently insignificant areas of operations. Any one of which could prevented an accident, but without assurance for the next one - the next unforeseeable one; thus broad based changes are preferred.
We cannot continue to consider safety as good or bad, because modern complex operations require continuous adjustment to new (emergent) challenges e.g. the surprise of RAAS TOGA interaction. Safety involves continuous activity to manage the operational probabilities in risk, we attempt to keep the odds as low as possible.
"Can we prevent pilots from failing to add thrust during a go around? Absolutely yes."
I disagree; but we might reduce the probability, by reducing surprise, workload, systems complexity, and the proliferation of SOPs.
Help pilots detect and correct any oversight, to do what they already do well, but better.
By focusing on just one item it is very difficult to avoid ending up blaming the pilot. The greater safety benefit is to explore why activities were not completed, or what factors might have contributed to an oversight, with the objective to aid crews alleviate the risks in these situations.
What has been published and discussed so far indicates that this was an 'unforeseen' accident; not an extreme unforeseeable event, but something which fell outside of the classic approach to safety. It appears to have emerged from a combination of factors involving many aspects of operation; these situations require a different approach to investigation and safety improvement.
For example, compare this incident with many successful GAs, where crew actions were correct, or if with deviation, were detected and corrected in time. Perhaps this accident involved an excessive variation in actions or corrective action took longer; the latter is more likely.
By considering the human as an asset in maintaining safety, as indicated by the successes of normal operation, then an output of accident investigation should identify aspects which increased the difficulty for the crew to act normally, and with this consider alleviation.
A major theme from the ASAGA report considered task saturation, workload, and time, against the backdrop of surprise.
Those aspect already discussed about systems integration, SOPs, and operational assumptions about new systems, should be reconsidered to reduce surprise, workload, etc, to effect change.
I refrain from choosing one item; emergent accidents require safety changes which involve many apparently insignificant areas of operations. Any one of which could prevented an accident, but without assurance for the next one - the next unforeseeable one; thus broad based changes are preferred.
We cannot continue to consider safety as good or bad, because modern complex operations require continuous adjustment to new (emergent) challenges e.g. the surprise of RAAS TOGA interaction. Safety involves continuous activity to manage the operational probabilities in risk, we attempt to keep the odds as low as possible.
"Can we prevent pilots from failing to add thrust during a go around? Absolutely yes."
I disagree; but we might reduce the probability, by reducing surprise, workload, systems complexity, and the proliferation of SOPs.
Help pilots detect and correct any oversight, to do what they already do well, but better.
td, the principle of tactile feedback is well established, but as with any good design the benefits can be circumvented by the method of use and the variability of human performance, particularly if influenced by conflicting advise;
E.g. always, always, use AT - as designed, as trained, as SOP, a fully automatic operation ... except when it isn't fully automatic.
Its the exceptions which usually get you
E.g. always, always, use AT - as designed, as trained, as SOP, a fully automatic operation ... except when it isn't fully automatic.
Its the exceptions which usually get you