Flight Directors off for stall practice in the simulator.

[Judd]

It is well known there are operators who mandate that the flight directors must be on and programmed for all phases of flight. There may well be technical reasons for this depending on aircraft design. That said, it would be no surprise to some, that automation dependency also plays a significant part with those sort of company directives.

During type rating training in simulators the approach to stall and stall recovery is usually practiced. This includes during on final approach in the landing configuration where ground contact is a factor. The pre-flight briefing may include FCTM advice such as "Ensure the proper flight director modes are selected for the desired manoeuvre. If the FD commands are not to be followed the FD should be turned off. Do not use the FD commands during stall recovery. FD commands are not designed to provide guidance to a recovery or approach to stall or stall."
The QRH also states under Approach to Stall or Stall recovery, a Note which says "Do not use flight director commands during recovery."

Having now set the scene, the decision has to be made by the instructor whether or not to turn off the FD for the exercise. On the other hand, as it is likely that in real life the FD will already be on during the instrument approach during which a stall or approach to stall has occurred, maybe the FD should be turned off for the recovery? After all, Boeing advice is: "If the FD commands are not to be followed the FD should be turned off."

Some may argue that because a go-around will take place once the aircraft has recovered from the stall, the FD should remain on during the manoeuvre to provide pitch guidance for levelling out at the missed approach altitude, if the stall occurred in IMC. Their argument being that the pilot should avoid being distracted by un-programmed FD indications and that he should be able "look through" the FD needles to see the nose attitudes during stall recovery. While some pilots claim that they can "look through" the FD indications to see what is behind them, others claim they are seriously distracted trying to see behind the needles and prefer to turn off the FD as part of the recovery.

The catalyst for this post was a colleague who was given a "Fail" mark for requesting his PM to immediately switch off both FD's as part of the recovery from the approach to stall. The instructor was of the view the FD should be left on during the whole exercise since the pitch bar indication would serve as a reminder of the missed approach altitude. While that may be true, nevertheless the priority in such a situation is a proper appreciation of nose attitude during the recovery; particularly as GA thrust used where ground contact is a factor, would cause a strong pitch up change of trim and may even lead to a delayed stall recovery. This is where raw data instrument flying skills become paramount. As Boeing reiterates: "Do not use FD commands during recovery." This would suggest that in event of an inadvertent stall the FD should be switched off so that pilots are not seduced into following erroneous or inappropriate FD commands .
Comments appreciated.

[763 jock]

The instructor involved sounds like one of those nit picking idiots we all encounter from time to time. What really matters is how the manoeuvre is flown and how controlled flight is restored without exceeding limitations.

Whether the flight director is ignored or switched off is really secondary and at best a discussion item. If it happened for real I suspect it would be at the bottom of the list of priorities.

I'm a TRE and would not award a fail simply because somebody chose to turn the flight director off.

[RAT 5]

In defence, m'lud:

The exercise was stall recovery. Did I achieve that satisfactorily? Yes. Is there a company SOP about FD's ON/OFF? No. Therefore should that have any effect on the assessment of the manoeuvre? No. IMHO. (TRE). Sounds like personal opinion, and failing on that basis for a specified manoeuvre seems overly harsh.
Should PF, during the startle factor of a stall recovery, be giving priority to FD's ON/OFF? Debatable. Should a current pilot be able to control attitude without an FD? Yes. FD is OFF, stall is recovered, TOGA is pushed with MAA set, would not the FD reappear until ALT AQ? Should that cue be enough for the level off? Probably.
Surely a fail for such an item has an appeal to HOT?

[FullWings]

The instructor involved sounds like one of those nit picking idiots we all encounter from time to time. What really matters is how the manoeuvre is flown and how controlled flight is restored without exceeding limitations.

Whether the flight director is ignored or switched off is really secondary and at best a discussion item. If it happened for real I suspect it would be at the bottom of the list of priorities.
Couldn’t agree more. Time-critical event training is all about reinforcement of technique for dealing effectively with something that would likely lead to a crash in short order if uncorrected. Stall, hard GPWS, windshear, airspeed unreliable, etc. The last thing you should be thinking of while flying these manoeuvres is artificial altitude constraints. It’s an emergency: the sky is yours.

Yes, when back in a normal flight regime you can start paying more attention to clearances, altitudes and the like but that’s sugar frosting compared with handling the escape correctly.

[Tee Emm]

Is there a company SOP about FD's ON/OFF? No. Therefore should that have any effect on the assessment of the manoeuvre? No.
That being so, why not leave the FD on while conducting steep turns as part of an IPC? After all, the pitch bar may help you to maintain altitude and the roll bar reminds you when to straighten up on the original start heading.. .

[safetypee]

Catch 22, a wicked problem, depends on viewpoint, on which window we look through; there are rarely answers. e.g. is your glass half empty or half full?

A quibble with language (my window) is that the good advice to ‘look through’ the FD is a normal function implying a combination of attitude and FD, whereas in a stall we would wish pilots to ‘ignore’ the FD - focus on attitude, probably an even more difficult task than combination. How do you mentally reject an information display which in normal circumstances could be the dominant reference, but where with the effect of surprise and startle in an emergency the mind reverts to first learnt, most used, information.

This debatable point offers a potential alleviation for all parties to understand the issue and to debate the relative safety merits of situations. Thus a learning view, vice an examining pass/fail position, would highlight the importance of understanding the situation, particularly the precursors, what is important, and how to avoid the situation; and if unable, how to recover.

We are told with these types of problems to look at the bigger picture. So my half-full glass, emptied into a larger glass could be judged near empty - best bitter please. And if you are having this discussion in a bar you are clearly drinking with the wrong people.

Thus this ‘technical problem’ (actually philosophical and human) should be posed to management - the bigger picture; as a safety report, to the manufacturer and regulator for a wider view of policies, design, training, examining, mandates, and choice and use of procedures.

[vilas]

FDs should be switched off if they are not to be followed is a general suggestions. It is applicable for any planned situation like visual approach. Steep turns are not done in commercial aircraft. Stall is not a planned manoeuvre. Once the aircraft has stalled at lower altitude immediate memory items for recovery should be applied i.e. lowering the nose, application of required thrust etc. Pilot who is doing the recovery should have the knowledge that FDs don't provide unstall guidance and ignore and just fly the attitude. If it's not in the procedure why waste time switching off FDs? It's a serious event and should have a standard procedure.

[Pugilistic Animus]

In the US on the ATPL practical test and initial type training a 45 degree bank angle steep turn must be completed

[Check Airman]

"Ignore the FD"

Easier said than done sometimes. I'd agree with the pilot in question. Turn off the FD. Fly the plane. Then worry about what the FD thinks about the FCU selections.

[Capt Pit Bull]

We could always go a bit radical and fly the recovery as specified by the manufacturer.

[Vessbot]

That being so, why not leave the FD on while conducting steep turns as part of an IPC? After all, the pitch bar may help you to maintain altitude and the roll bar reminds you when to straighten up on the original start heading.. .
So that we don't remove the 5 minutes per year of practice of raw data flying that airline pilots get?

[rak64]

Do not use the FD commands during stall recovery.
Actually, you can use the FD; one useful information is the altitude selected (if it was). It is easy to climb back to cleared altitude while using the FD after recovering.

[vilas]

Ignore the FD"
Easier said than done sometimes. Sure! But isn't this a simulator exercise? We practice in simulator many things that are not that easy to acquire competance to do them in real life when the need arises. In Airbus if stall happens when the bird is on hitting TOGA will bring FDs back. So good practice to fly ignoring FD. I think the important thing is to be able to apply immediate recovery actions with or without FD.

[IFLY_INDIGO]

just like in TCAS RA, stall recovery has nothing to do with FDs. FDs must be switched off if you get into stall for more focused recovery.

[vilas]

INDIGO
Surely FDs have nothing to do with recovery from stall and they can be confusing if one doesn't know that they are not to be followed. In TCAS immediate action is FDs off and it is mandatory for a different reason. In automatic TCAS you don't switchoff the FD. EGPWS is a memory item where you ignore FDs. Stall recovery also is a memory item and it doesn't contain action on FDs. In low level stall one doesn't know how much height will be lost. The immediate actions in a stall are reduction of a AoA, wing level, thrust as required, checking speed brakes in which the PF must do before doing anything else. Forgetting any of these can be fatal. Putting the nose below the horizon with FD on or off should not be a such big deal. You may be doing the approach with the bird and if switch off FD first it will reappear with TOGA then you again switch it off? Obsession with FD off which is not essential action can also become a distraction and make you forget something more critical to recovery.

[Tee Emm]

So good practice to fly ignoring FD.
Easier said than done; like ignoring the guy coming your way at night and blinding you with his headlights on High beam

[Centaurus]

Pilot who is doing the recovery should have the knowledge that FDs don't provide unstall guidance and ignore and just fly the attitude. If it's not in the procedure why waste time switching off FDs?
Airline pilots probably spend 95% of their flying hours following flight director commands. All the more reason for switching the FD off in a critical situation like a stall recovery where blindly reverting to habit and following FD needles could lead to a more serious problem.

[vilas]

Then why it is not a memory item? All memory items are laid down procedures. Is it because the manufacturer is not capable of thinking like us? And about stall only the test pilot has actual experience. It may not be easy that is why we practice in the Sim. Switching off FD is helpful but not at the cost of mandatory actions. Flying accurately and not stalling in the first place appears simpler than recovery. Most stall incidents are because of poor flying.

[White Knight]

We could always go a bit radical and fly the recovery as specified by the manufacturer.

My thoughts exactly:ok: Fairly pointless discussion about the FDs.

[Piltdown Man]

“Failing” someone during trading is a good measure of a company’s training standards and the trainers within. It happens, but normally this is for repetitive gross handling errors, diabolical CRM, dreadful preparation. But a “fail” for asking for the FD’s to be turned off? This speaks volumes. As has been pointed out already, the FD should not be followed for a recovery because it will not give any useful information. It would also be reasonable to question its validity following a stall recovery. The only issue I could see is do you actually need to turn the things off as it would be better to concentrate on the recovery rather than flick switches.

PM

[pineteam]

FDs are great tools for guidance but pilots should know when it's time to ignore them even in normal daily operations: For example a very bumpy approach couple with a potentially unstable glideslope guidance ( Eg Beijing ILS 36L) trying to chase the FD bars accurately when the aircraft is tossing around is almost impossible and certainly not recommended. Knowing the pitch and power of your aircraft is a must.

[Centaurus]

FDs must be switched off if you get into stall for more focused recovery
Interesting observation. Hand flying while following FD commands normally requires full concentration on keeping the FD needles centred in the tiny square. The theory being if the needles are exactly centred then eye scanning of other pertinent instruments are of secondary importance. Pundits will claim that despite FD's being prominently displayed, the pilot should still use the six pack scan in the PFD. Ideally yes - but that rarely occurs. With many pilots, Situational Awareness can go out the window the moment they are locked on to the FD.

With engine failure at V1 and continue, some pilots have trouble following FD commands and often overcorrect. The result is they start to chase the needles which only makes things worse. One temporary solution is to switch off the FD. This clears the PFD so the pilot can concentrate on the "little aeroplane" nose attitude and bank indications. Others simply switch their scan to the standby ADI and fly on that, which is devoid of distracting needles. When introducing engine failures on take off for the first time, it can be helpful for the candidate to practice these with FD's off so that a clearer picture of the artificial horizon is seen without the distraction of wavering FD needles . Once the candidate is competent at flying this raw data display, FD use can be introduced.

[Check Airman]

The FD isn't a no-go item. With the exception of a handful of procedures, its use is at the discretion of the PF. If the PF says FD off, then FD off. Particularly in a stall, where the FD will be commanding the exact opposite of what needs to be done (se AF447) it's a useless instrment. Why expend the extra brain power to look behind the FD when you can just turn it off?

[safetypee]

W Knight, et al, the original question is at the heart of many safety issues; it’s not just the FD, but human - system interaction and the wider issues of system design, training, checking, procedure advice / mandate, etc.

It’s difficult to ignore salient guidance cues overlaying the primary reference instrument - fundamental aspect of human performance - a similar cognitive feature as with illusion, how do you ignore an illusion (only after you realise that you have been mislead? ).

For those who wish to switch the FD off, another SOP, more paper work, memory item, and another opportunity to ‘fail’; how often do SOP writers ‘fail’.

It is impossible to expect every pilot to remember to take the correct action in every situation, particularly with the surprise of stall warning or stick push. Evidence from many accidents suggest that humans forget when surprised, cross crew monitoring and communication break down. ‘Pilot did not follow SOPs’, ‘did not recover from the stall using the correct procedure’, weak CRM, etc.

Many of modern day safety issues challenge the concept and limits of human performance; we cannot know and recall the ‘right’ thing to do in every situation.
The industry requires a different approach for these issues, but change is far from easy.

For those who favour automation, when do you remove the FD. Most aircraft use the FD for Windshear recovery which might infringe stick shake and then you inhibit valuable guidance.
Alternatively it should be possible to provide FD guidance for stall recovery, but would the effort of design, test, certification, not for all stall / upset scenarios, be cost effective if compared with efforts to avoid stall situations.

And as much as I favour spreading problem to a wider audience - management, regulator, manufacturer; action depends on their perception of the issue (or willingness to ‘see’), their view of safety priorities, or if there is a viable cost effective solution; so nothing happens.
On the other hand there may be great satisfaction in passing the problem on, being able to ‘blame’ someone else, “oh I told you so” after an event. cf 777 Asiana autothrust, 737 THY Rad Alt/autothrust, and as many examples as you wish to find or refute depending on your viewpoint.

“Wicked” problems can't be solved, but they can be tamed; how, recognise that there is a problem and be prepared to talk about it.

[IFLY_INDIGO]

Then why it is not a memory item? All memory items are laid down procedures. Is it because the manufacturer is not capable of thinking like us? And about stall only the test pilot has actual experience. It may not be easy that is why we practice in the Sim. Switching off FD is helpful but not at the cost of mandatory actions. Flying accurately and not stalling in the first place appears simpler than recovery. Most stall incidents are because of poor flying.

Manufacturer keep revising abnormal procedures in the light of new information. Even memory items have been revised time and again. Having conflicting information display is not good airmanship. If not PF, it may confuse the PM and trigger wrong callouts. We also have danger of mode reversion if we don't follow the FDs.

[vilas]

Indigo
Does Airbus permits the operator to modify abnormal / emergency procedures? you yourself just started and ended this thread. So what happened to your opinion now? Stall recovery is a memory item more serious than that. Nobody follows FDs in stall recovery but when exactly you switch them off? What is the priority. Why not check with the manufacturer first and let us know?

[vilas]

INDIGO
We also have danger of mode reversion if we don't follow the FDs. That is interesting. Since we are discussing stall we can only be in alternate law. So no hard protections which cannot be overridden and no auto pilot. ATHR may or not be there.Now let's see mode reversions. I assume you are referring to Speed protection when FD orders are not followed by the flight crew(AP NOT ENGAGED). In these protection there are two dimensions one is when the speed increases to VMAX+4 and the other is when speed decreases to VLS-2 or with speed brakes extended VLS-2 to VLS-19. Speed increase won't bother us because aircraft will not stall. If speed decreases below the value mentioned above then FD bars disappear. If A/THR active, automatic engagement of SPEED mode on the A/THR. Thrust increases to recover the speed target. So again no stall so where the danger that you see. Rather it is good. The very purpose of reversion is to prevent speed reduction below unsafe level.

[vilas]

If you treat stall as an upset then in FCTM Upset Prevention and Recovery Nose High recovery it suggests disconnection of AP and ATHR.

[RAT 5]

From a practical point of view, B737, the stall recovery manoeuvre would likely be prompted by the stick shaker. The response should be instinctive. The incipient stall would be broken PDQ. My concentration would be on that; i.e. attitude, speed then power. It would be pretty quick, even at altitude. I doubt I'd have the time to think about FD's or not.

[IFLY_INDIGO]

Indigo
you yourself just started and ended this thread. So what happened to your opinion now? Stall recovery is a memory item more serious than that. Nobody follows FDs in stall recovery but when exactly you switch them off? What is the priority. Why not check with the manufacturer first and let us know?

Stall recovery is a flying technique, not an ECAM drill or QRH/FCOM procedure.

Airbus golden rule says use appropriate level of automation and I consider FD as part of automation. In stall recovery, main action is lowering the nose. Afterward, it is about recovering the speed and flight path. At this time, if FDs give me conflicting information, I would ask for turning them off.

[vilas]

Stall recovery is a flying technique, not an ECAM drill or QRH/FCOM procedure. This can be a subject of a new thread. Stall is very much part of FCOM and QRH Abnormal Procedures. It is also a drill. Only difference is it is done by memory because life is too short. It is part of abnormal procedures in both the documents mentioned.

[vilas]

https://cimg3.ibsrv.net/gimg/www.gmforum.com-vbulletin/1920x1080/screenshot_20180621_121105_bfd2e597798670a57386f193d6cf6d828 4e20481.png

[vilas]

This is from Flight Crew Techniqes Manual

[FE Hoppy]

Good luck turning them of on the CSeries. They come on automatically at under-speed and you cant turn them off until you are recovered.

[vilas]

Good luck turning them of on the CSeries. They come on automatically at under-speed and you cant turn them off until you are recovered. And still the pilots fly without raising a hue and cry? Shall I call them brave?

[wiedehopf]

Good luck turning them of on the CSeries. They come on automatically at under-speed and you cant turn them off until you are recovered.

So the only reason for that behaviour would be that the flight director actually gives useful cues to get back to speed. Sounds like a good feature for Airbus, kinda like a mental stick pusher for followers of the magenta line.

[pineteam]

Because pressing buttons on the FCU will save the day... xD. If you are stalling, first you would need new undearwear, then you better make sure the PF is reacting accordingly and as a PM, checking your FMA carefully and ready to take control as an incorrect corrective manoeuver will kill you. If you are worried about the FDs bar in a stall, it’s probably too late..Any onset of the stall in cruise shall be instintive and FDs ignored. Period.

[Cough]

Personal take...

F/D's on/off during a stall recovery... In my book, whatever. As quoted above, you ignore them anyhow.

My issue is distracting the PM (essential part - right!) from the monitoring task during the recovery by asking for the FD's off. The PM simply isn't expecting it! Will take them by surprise and distract them from the key monitoring function.

Was it a fail though? Errrm, (IMHO) No way! Discussion item, but only if the examiner is feeling picky!

[Centaurus]

The PM simply isn't expecting it! Will take them by surprise and distract them from the key monitoring function.
Then he is going to get one hell of a surprise when something really serious happens on his watch if hasn't the cognitive capacity to switch off a FD switch in the one second it takes to do so. Jesus Wept. Has aviation got to the stage that we have to baby pilots that much, or are we so overwhelmed by the myriad of SOP's that are pushed down our throats in today's airline flying, that one slight item out of order is practically a Mayday situation?

[Cough]

Ok...Take this from the PF point of view...

Do you want them distracting themselves by looking at the FD, thinking of random rule number 17 and three quarters, thinking 'well I'm not following that so I must call for it to be turned off' (your myriad of SOP's...) or do you just want them to unload the wings using a simple tried and tested method and recover the aircraft.

ie. concentrating on the core task of recovering the aircraft in a time critical scenario.

[swh]

just like in TCAS RA, stall recovery has nothing to do with FDs. FDs must be switched off if you get into stall for more focused recovery.

The reason the FDs should be turned off is they are telling you and the aircraft how to fly what is set in the FCU. With a stall recovery or TCAS this may command the opposite thrust you require.

Turning FD off results in a speed mode independent of the FCU.

[IFLY_INDIGO]

This can be a subject of a new thread. Stall is very much part of FCOM and QRH Abnormal Procedures. It is also a drill. Only difference is it is done by memory because life is too short. It is part of abnormal procedures in both the documents mentioned.
not in QRH anymore.. yes, it is in FCOM as a memory item.

I will also follow golden rule 'Use the appropriate level of automation at all times' and switch off FDs if they were on.

[Capt Pit Bull]

This thread is ridiculous.

AIRCRAFT CONTROL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> fiddling with flight guidance

It takes ... what, about 4 seconds? to say "FLIGHT DIRECTORS OFF" and for PM to then do it.

That's about four seconds more than pushing the column forward to start reducing the AOA. <------ (Remember that whole 'how to unstall an aircraft 1.01' thing)

Are some of you muppets going to sit there frozen, unable to reduce AOA until the flight guidance is removed?

Hand your licence in.

Are any of your colleagues going to do that? FAIL THEM, or feckin SHOOT them.

I don't care which, but they are too retarded to fly an aircraft.

[harrryw]

I would have thought any pilot would be able to say "Flight Directors OFF" at the same time as he is pushing the stick forward.

[pineteam]

It's easy to ask for FDs off and turn them off in normal sunny daily operations. But when the workload is significantly more than usual, I saw guys pressing the ILS p/b instead of the FDs p/b or only pressing one of them when I asked for Fds off. Or sometimes a simple task of challenge and response during landing checklist can be challenging and slower than normal.

So now imagine during a stall... xD.

I'm with Vilas and Cpt Pit Bull on that one. The waste of time for asking for something non standard in an upset situation that even a delay of a fraction of a second can be fatal is not a good idea. The priority is always to FLY first.
And 'FLY' means for the PM: ''He must assist the PF and must actively monitor flight parameters and call out any excessive deviation. The PM's role of actively monitoring is very important'

In a stall monitoring is much more important than playing with the FCU.

80% of the aircraft accidents are due to poor monitoring according to Air France.

[vilas]

INDIGO
It is simple in the SIM to just bring THR LVRs to idle and stall, push the stick forward and recover. For all you know the aircraft hadn't stalled because present simulators are not representative of deep stall and you are not allowed to practice deep stall. So if you did nothing else it wouldn't matter. In Perpignan and AF 447(although self created) the stab had auto trimmed way up and to unstall it required to manually trim forward otherwise recovery was not possible. In another you may require to retract speed brakes or make wings level. These are all critical actions and they need to be done by memory instantly and the PM has to ensure you do or he has to remind you or do them himself. If you forget to switch off FDs it is not disastrous like forgetting the other things. In a hurry in TCAS I have seen people switching on the LS button instead off switching off FDs. FD on or off shouldn't paralyze anyone. Golden rule 1 fly the aircraft. You can't fly a stalled aircraft unless you unstall it. So first unstall it. Then fly it back to the flight path. It seems that all memory items have been removed from the QRH. But stall recovery is discussed in the FCTM and it doesn't say anything about FDs.

[Tee Emm]

80% of the aircraft accidents are due to poor monitoring according to Air France

Of course, Air France would say that, wouldn't they? How about 80% of accidents are due to the PF's poor instrument flying ability?

[vilas]

If anyone wants detailed procedure following is from Airbus Safety First:
https://cimg2.ibsrv.net/gimg/www.gmforum.com-vbulletin/1080x1920/screenshot_20180623_191642_111a81cd42afdaaec15fa3935603dddc8 57e5874.png

[pineteam]

Sure. But the point is that even if it’s a clown as PF, as long as the PM is doing his job properly, things should not go out of control. Eg like when the PF is doing a raw data approach, the PM must call out any deviations. If he does it accurately the PF will be aware and correct his mistakes immediately and always be stabilized. If PF does not react, PM should take control. Same case shall apply in a stall situation.

[Tee Emm]

It is simple in the SIM to just bring THR LVRs to idle and stall, push the stick forward and recover. For all you know the aircraft hadn't stalled because present simulators are not representative of deep stall and you are not allowed to practice deep stall. So if you did nothing else it wouldn't matter. In Perpignan and AF 447(although self created) the stab had auto trimmed way up and to unstall it required to manually trim forward otherwise recovery was not possible

Further to the subject of stall recovery, it is interesting to study the Turkish Airlines B737 crash at Amsterdam see: https://www.google.com.au/search?source=hp&ei=DFEuW4azJ5b4hwP40aeQDQ&q=Turkish+Airlines+crash+at+Amsterdaam&oq=Turkish+Airlines+crash+at+Amsterdaam&gs_l=psy-ab.3..0i22i30k1l6.4020.17250.0.18066.36.36.0.0.0.0.666.7038. 0j2j24j1j0j1.28.0....0...1.1.64.psy-ab..8.28.7020...0j0i131k1.0.GaJ3YewRW-M
Some operators, during type rating training where the syllabus requires approach to the stall recovery action, have replicated the events that led to that disaster. One of those events was the almost continuous back trimming of the stabiliser as the autopilot attempted to maintain the ILS glide slope after the thrust levers went to idle.

At stick shaker with an airspeed of (from memory) approximately Vref minus 25, the stab trim had wound back to about 12-14 degrees back trim instead of the usual seven degrees setting at landing configuration. In the simulator, when recovery at stick shaker is attempted in this situation, the pitch up at firewall thrust is really significant and can lead to a full power stall if not contained. This is because the forward elevator forces needed to contain the pitch up at full power, are so strong and need to be relieved by immediate forward stabiliser trim action which requires about 5-7 seconds of continuous nose down stabiliser trim. Care has to be taken not to over-trim of course; but five seconds of continuous forward trim should get you out of immediate trouble as by then the stab trim will be around 5-7 degrees as in a normal go-around situation.

. At the same time the pilot needs to carefully adjust the pitch angle to remain around 5-8 degrees nose up as a compromise between flying into the ground while trying to increase airspeed, and pitching too far up to prevent a secondary stall warning. Once Vref is reached, the flaps can be retracted to flap 15 as in a normal go-around and body angle adjusted as per normal go-around procedure. None of this assumes the aircraft is in a deep stall. if that happens at low altitude, all bets are off and the devil take the hindmost..

[vilas]

At stick shaker with an airspeed of (from memory) approximately Vref minus 25, the stab trim had wound back to about 12-14 degrees back trim This is digression but since you mentioned I need to comment on these accidents. This Vref-25 in Turkish, Vref-27 in Indian Airlines, Vref-31in Asiana with two pilots sitting in front and in two of these during command checks, in absolutely fine weather is simply unacceptable standard of piloting. Automation dependency means inability to fly without automation not inability to monitor flight path on auto pilot. I don't think they had the required scan to apply the stall recovery procedure at low level.

[Vessbot]

There's no easy straightforward answer here.

On one hand, the primary task is to fly the plane and put the nose down with no delay and no interference.

On the other hand, given the strength with which the propensity to follow the FD is burned into our brains, its remaining visible is enough of an interference to the primary task, as to matter. From my observations, I can confidently guess that I use the FD by far the least out of my airline of 2000 pilots, and even for me, whenever it stays up because the other guy is too busy answering a radio call or whatever to change the dial the appropriate settings into the panel, it is extremely difficult to ignore it. Fighting the urge to follow it is a significatn distraction to the flying task.

Of course, one way to (at least partially) resolve this contradiction is for the PF to use his own mouth and the PM's hands to turn off the FD, leaving his own hands available to fly the plane. But then (if the story is told accurately) he runs into an idiot instructor who has taken it upon himself to reinforce automation dependency by forcing its use in inappropriate situations. It has literally become a taboo to not have the FD visible as its lack evokes a gut discomfort. It's somehow better for these people for it to be up and displaying a wrong command, than for it to be hidden.

For those strongly putting forth the notion that the FD is to be ignored, well... if wishes were horses then beggars could ride. We saw how that ended up with AF447 and the +8000 fpm FD that popped up in the midst of their startle and confusion.

For every child of the magenta that has flown a flyable airplane into a well publicized crash, there are hordes of ones latently plodding along without incident in normal operations, ready to make the same mistake when operations stop being normal. The mental conditions are there, just waiting for a trigger.

[Pugilistic Animus]

It is more exacting to write "stall off for Flight Director practice in the simulator" :}

[PPRuNeUser0190]

Wow, a lot of discussion for a no-brainer imo. First fly.

stall (warning) --> nose down. Once the recovery is initiated, analyse your current state and continue the recovery (with or without F/D present).

Are you going to discuss as well if the airplane shouts "pull up, pull up"? Firewall and 20° up (on my aircraft), then think about the details.

[vilas]

We saw how that ended up with AF447 and the +8000 fpm FD that popped up in the midst of their startle and confusion. I think you should leave AF447 out. It's a wrong example to quote. When audio is blaring stall, stall you don't follow FDs. AF447 crew never realized the stall.

[KayPam]

My opinion (student pilot, currently PPL IR) is that the FDs should be used in order to improve accurracy.
I'm thinking I should bank 17° right and pitch 3.5° up, my FD tells me 18° right and 4° up, ok then, I'll follow it.
If it tells me 15° left, and if I'm sure of my 17° right, I will have no moral or ethics problem at all with shutting it off. Or even more shocking for my instructors, no problem at all flying opposite the FD. Even more so when the reason why the FD is not aligned with my idea is known. E.G I'm in heading or nav mode but I am willingly taking a turn for weather avoidance. In this case I know the FD directs me into an unwanted situation : **** it, I'll do what I know is better.

The fact that professional pilots would follow the FDs instruction without thinking twice, or even worse that instructors would train people to do so, frightens me.

[Vessbot]

I think you should leave AF447 out. It's a wrong example to quote. When audio is blaring stall, stall you don't follow FDs. AF447 crew never realized the stall.

I'm not following your reasoning as to why the example doesn't apply. Are you saying "you don't follow FDs" as something you shouldn't do? If so, I agree. Are you saying it as something that doesn't happen at inappropriate times? Then I disagree. They may or may not have realized the stall, that's something we can only speculate on. That they did not act properly on it, we know for for certain.

Even if they did realize it, that in no way prevents them from reacting to it the wrong way in the face of overwhelming urges (1. if in trouble, pull up, and 2. follow the FD)

If they did not, surely the FD commanding +8000 fpm would have acted as a contributor to their false information that is the basis of their failure to recognize it.

[vilas]

Vessbot
I really gave a serious thought to avoiding reference to 447 because despite twenty thousand posts and a decade later it refuses to die. I only hope I already haven't done the damage.

[Pugilistic Animus]

AF447, oh no we're going under :\