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-   -   Blind following of flight directors yet again (https://www.pprune.org/tech-log/638981-blind-following-flight-directors-yet-again.html)

Centaurus 2nd Mar 2021 00:37

Blind following of flight directors yet again
 
B738, vicinity Bristol UK, 2019 - SKYbrary Aviation Safety

Pilots blindly following the flight director regardless of its veracity. The Children of the Magenta Line syndrome continues to defy common sense.

Uplinker 2nd Mar 2021 09:06

From the report it looks more like a rushed and impossible approach to me - especially with the reduced track miles. They were too close with too much energy to accept the shorter routing.

They then seem to have got into a right bugger's muddle with the 737 "automation" and were at least 10nm behind the aircraft - not a good place to be.

Whatever it was, it seems amazing that pilot recruitment these days concentrates on how many verbal reasoning and maths questions you can do in 10 minutes, and clever answers to HR questions, rather than being able to actually fly a plane with Situational Awareness.

D9009 2nd Mar 2021 10:53

I suspect that these qualities are the ones that prevent you from getting into such sticky situations which require the flying ability to get you out of.

Uplinker 2nd Mar 2021 11:10

No. That comes from experience. Flying experience prevents you getting into a bad situation in the first place, e.g. trying to approach within too few track miles.


D9009 2nd Mar 2021 11:23

Let's look at the article shall we..."It was noted that the 55 year-old Captain had been acting as PM for the flight until he took over control when the aircraft began to descend soon after the go around had been initiated. He had a total of 14,750 hours flying experience which included 10,770 hours on type."

Can't see a lack of experience here.

Uplinker 2nd Mar 2021 12:53

Yes, I walked into that one didn't I :)

However, the verbal reasoning and maths tests don't seem to have helped this Captain either.

D9009 2nd Mar 2021 14:40

I'd put my money on fatigue and commercial pressure for this sort of misjudgement.

Tinribs 2nd Mar 2021 17:27

Some of the old/bold treated the FD with some suspicion They used to tell a story about Ron Hardy, BMIs much respected chief pilot, who always did his checks with the most junior instructor in the fleet. As an engine failure at V1 = 1 knot happened and there seemed little input from him except a couple of tweaks to the trimmers, the instructor leant forward and said "follow the command bars captain", Ron pushed his seat back removed his hands and feet from the controls and watched. The sim ran along the runway rotated and climbed away. Ron turns to the instructor and says see what I mean?. These, points to shoulder, are command bars, they are advice bars

john_tullamarine 2nd Mar 2021 19:27

Moved from CRM to Tech Log at OP's request.

While we can all make mistakes with profiles, I recall at AN as a young chap there was a great emphasis on keeping the mental picture going throughout the initial pre-descent and descent proper. Folks tended to have the descent profile where they desired throughout with a bit of ROD tweaking as required while the altimeter wound its way down.

Flexible thought processes facilitated out of left field recoveries (eg air traffickers' needing to keep the aircraft high due to traffic conflicts and so on). For sure the boxes do a useful job but, unless the pilot knows what is what, or lets his/her guard down, it is easy to allow the gee whizz stuff first to seduce and then to leave one in flagrante. Not infrequently, say coming into SYD from the north for a straight in landing during busy periods, one could find oneself exploiting the steep side of the aeroplane's descent capability.

More importantly, one recognised early when one really needed an orbit or some extra track miles to run and that made things easier for everyone concerned.

Vessbot 2nd Mar 2021 20:29


Originally Posted by Uplinker (Post 11000281)
From the report it looks more like a rushed and impossible approach to me - especially with the reduced track miles. They were too close with too much energy to accept the shorter routing.

They then seem to have got into a right bugger's muddle with the 737 "automation" and were at least 10nm behind the aircraft - not a good place to be.

Whatever it was, it seems amazing that pilot recruitment these days concentrates on how many verbal reasoning and maths questions you can do in 10 minutes, and clever answers to HR questions, rather than being able to actually fly a plane with Situational Awareness.

The sudden cutting of track miles opening the door to the ensuing chaos was certainly a part of it. The blind, task-saturated FD following (in day VMC, at that) was another. Both were fully factors in their own right, and the importance of one does not diminish the other (as in "more like a..." comparison).

If they had a normal, calm approach then the whole event probably would not have happened, yes; but the underlying inability to break away from the FD would still be there, only hidden and waiting for some other triggering event.

It's disappointing but not surprising. The FD taboo is so pervasive that I remember one sim where we had a PRM breakaway, which is mandated to be hand-flown (at least for us) due to the time criticality. OK, we get the breakaway vector and I start flying it. Then some other radio-related stuff happens and the other pilot can't get to the FCP to set the heading bug and modes. I turn off the FD as it's a distraction making flying difficult (giving a full opposite turn indication, and the wrong vertical command as well), and the sim instructor scolds me for doing that and decreasing the available SA tools, or some similarly deranged take.

Vessbot 2nd Mar 2021 20:30


Originally Posted by D9009 (Post 11000364)
Let's look at the article shall we..."It was noted that the 55 year-old Captain had been acting as PM for the flight until he took over control when the aircraft began to descend soon after the go around had been initiated. He had a total of 14,750 hours flying experience which included 10,770 hours on type."

Can't see a lack of experience here.

I'm not seeing experience either, until more details are specified. How many of those hours are flying in something other than a straight line or climbing turn, with the FD on?

CaptainMongo 2nd Mar 2021 20:42

The SA of the crew was already gone at 10,000’. Intentional non compliance with regard to airspeed? I doubt it, that AS exceedance points back to lack of SA. UAS, already there at 10,000 above the ground, they just didn’t know it. Blindly following the FD was a symptom of the problem.

FDR data showed that once descent from FL100 commenced, the crew set the Bristol QNH of 1019, deployed the speed brakes and increased the ‘Selected Airspeed’ to 300 knots. This airspeed was selected despite the fact that the maximum permitted airspeed below this altitude in UK airspace is 250 KIAS.

DaveReidUK 2nd Mar 2021 23:01

Discussed here when the report was first published in May 2020:

PPRuNe: Blind use of flight director could have led to crash

Caboclo 3rd Mar 2021 00:26

Slightly off topic, do any of you folks feel that the automation in modern jets is so complex as to be a hindrance, rather than a help? I fly a DC-9 myself; my automation is anything but complex, and I kind of like it that way. I see so many accident reports referencing different modes of automation, and pilots confused about which mode is selected. Granted, many of these accidents also occur with poorly trained crew, but training aside, has the industry gone too far with the bells and whistles?

Check Airman 3rd Mar 2021 01:54

I feel I have a firm grasp of the different modes available. I agree with what Vessbot said in post 10- when it becomes a distraction, turn it off.

vilas 3rd Mar 2021 09:14

What being children of magenta, following FDs blindly got to do with this incident? The pilot simply had no idea what to do with vertical displacement closer to runway. By disconnecting automation he wasn't going to get some revelation about what to do. Without any plan in mind he should have declined the offer. But if he wanted to give it try he had to create high ROD at slow speed and not by diving at high speed in clean configuration. Just pull the speed brake(initially), put gear down and configure all the way to Vapp and then descend at the resultant high ROD and would have made it. He went Karachi PIA way. Didn't they fly manually and still crash?

Vessbot 3rd Mar 2021 15:53

It seems you're addressing an earlier part of the event (the flurry of late and half-understood mode changes in the approach) than the thread title (the descending go-around).

Fursty Ferret 7th Mar 2021 12:34


They used to tell a story about Ron Hardy, BMIs much respected chief pilot, who always did his checks with the most junior instructor in the fleet.
Not sure about you, but that story doesn't do anything to impress me. Sounds more like a deliberate attempt to get one over on a junior instructor.

Most modern aircraft will fly away safely after an engine failure with no control inputs provided there's sufficient excess power and they're not grossly out of trim (used to be a sales technique on the A320 series).. Whether they'll clear the mountain in the distance is a totally different question.

Alpine Flyer 10th Mar 2021 20:17


Originally Posted by Caboclo (Post 11000715)
Slightly off topic, do any of you folks feel that the automation in modern jets is so complex as to be a hindrance, rather than a help? I fly a DC-9 myself; my automation is anything but complex, and I kind of like it that way. I see so many accident reports referencing different modes of automation, and pilots confused about which mode is selected. Granted, many of these accidents also occur with poorly trained crew, but training aside, has the industry gone too far with the bells and whistles?

The oldest commercial plane I have experience on was a 1970s design and the newest is a 2000s design. I don't think that automation has advanced to the point of being a hindrance. I recently had a look at some older aircraft's checklists, all of which were considerably longer and more complicated than those of my current steed. Less switching during turn-arounds and during taxiing is a welcome reduction in workload (which helps to offset the additional chores introduced by FMS programming and switching from paper to EFB plus the various CYA paperwork introduced over the last 30 years). Less switching during abnormal ops will leave more capacity for the PM to monitor and the commander to manage.

Transitioning to more advanced avionics designs will result in some "what's it doing now" moments but usually you get to know the possible tripwires rather quickly.

What might be an issue is the lack of experience with "fallback options", e.g. pilots not being used to fly conventional navigation SIDs without FMS guidance any more. That needs to be trained and pilots should be allowed and encouraged to reduce the level of automation used during normal operation to stay sharp. Company policies or individual captains prohibiting this are counterproductive.

When I started flying we were rather proud to be able to use the full operational envelope of the aircraft. Over the years a lot of its edges have been declared no-go in the interest of safety (the theoretical underpinning being that using the edges increase the chances of transgressing them and scraping metal.) While this apparently has improved safety, it has also eroded pilots' abilities to deal with those edges. I am not entirely sure that is good, but far from being able to offer a comprehensive alternative.

FlightDetent 10th Mar 2021 20:42

What a voice of reason! :D :ok: :)

The average pilot has de-skilled in aviating and transformed to a higher level of being in conducting himself. The latter pushed out the former, made possible through evolution of technology. The overall result is a less-accident prone commercial aviation by order of magnitude or multiples of.

N.b. holes below the waterline need to be plugged no matter the skill-set involved. The newly achieved increased safety level, combined with less exposure to risks, presents a steeper slope to complacency than before. The arousal-stress / performance curve explains.



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