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-   -   Air France B777 control issues landing CDG (https://www.pprune.org/rumours-news/646054-air-france-b777-control-issues-landing-cdg.html)

212man 7th Apr 2022 16:18

I'm assuming the translate to "guide us with tail wind" really means "turn/vector us downwind"?

alf5071h 7th Apr 2022 17:56

Thank you ekhard et al; thus my translation is that a pilot (PF) has hands on stick and throttle, crew push buttons.

And for, and in-between these states the critical need to understand the situation, including the manoeuvring capabilities of manual and automatic aircraft control - in less than ideal circumstances.

‘Hands on’ adjustment requires a wide situational view - the map, even look outside, the big picture.
‘Button push’, linear, sequential, procedural adjustment via FMS and / or autoflight.

Which has the greater flexibility, the reactive capability in the situation - knowledge, experience.

glofish 7th Apr 2022 17:58


Originally Posted by 212man (Post 11212021)
I'm assuming the translate to "guide us with tail wind" really means "turn/vector us downwind"?

That is correct. Vent arrière means downwind in french.
I had written this earlier, before the "gentils modérateurs" censured the contribution .......

Capt Kremin 8th Apr 2022 00:19

There was nothing wrong with the aircraft. The crew had the wrong runway/approach selected and tried to override the AP manually. The subsequent go-around was incorrectly handled in that they retracted the gear before the initial stage of flap, hence the config warning.

hans brinker 8th Apr 2022 03:55


Originally Posted by Capt Kremin (Post 11212212)
There was nothing wrong with the aircraft. The crew had the wrong runway/approach selected and tried to override the AP manually. The subsequent go-around was incorrectly handled in that they retracted the gear before the initial stage of flap, hence the config warning.

Source?..............

5star 8th Apr 2022 05:35


Originally Posted by Capt Kremin (Post 11212212)
There was nothing wrong with the aircraft. The crew had the wrong runway/approach selected and tried to override the AP manually. The subsequent go-around was incorrectly handled in that they retracted the gear before the initial stage of flap, hence the config warning.

oh dear Lord help us….
I thought we had seen it all at AF !
There used to be a very good video on Youtube about AF pilots.`The title (in French) translated into something like : ‘ Aaah at AF….where the pilots taught the birds how to fly…’.

Surely Boeing will come out with a report…
Been flying the Triple for nearly 20 years and have never seen or read this kind of behavior by the AP.
Imho it’s still IS one of the most reliable airplanes in the industry….

JPI33600 8th Apr 2022 07:48


Originally Posted by Capt Kremin (Post 11212212)
The crew had the wrong runway/approach selected and tried to override the AP manually.

This seems extremely unlikely. During its descent, the aircraft was (presumably under AP control) traveling east-west and aligned with runway 26L, which is the most southbound runway at CDG. Therefore, the left deviation from this initial trajectory, either AP- or human-commanded, puts the aircraft even more south of CDG, where there isn't any runway.

Would the crew had erroneously selected e.g. 26R instead of the desired 26L, your explanation could make sense (pilot trying to chase 26L manually at the very last moment), but then we would have seen an initial descent towards 26R, wouldn't we?

Care to explain your point in a more detailed fashion please?

josephfeatherweight 8th Apr 2022 08:30


Originally Posted by Capt Kremin (Post 11212212)
There was nothing wrong with the aircraft. The crew had the wrong runway/approach selected and tried to override the AP manually. The subsequent go-around was incorrectly handled in that they retracted the gear before the initial stage of flap, hence the config warning.

I imagine that Capt Kremin has taken a bit of a punt here based on the sounds in the background and I’m going to say, I reckon he is either correct or very close to it!

H Peacock 8th Apr 2022 11:02

Was is not AF who tried to get a 777 airborne with the AP engaged on the ground? Heavy controls interpreted by the PF as a malfunction, so it resulted in a very high-speed abort! 🤔

Fursty Ferret 8th Apr 2022 11:38


Therefore, the left deviation from this initial trajectory, either AP- or human-commanded, puts the aircraft even more south of CDG, where there isn't any runway.
If they were set up for the other runway, then it would go straight through the 26L localiser to the south without capturing. Then in the go-around it would turn sharply north to intercept the missed approach course.

I'd be sceptical but I've seen AF land a 777 after making a very similar mistake in the USA. We almost went around due to the subsequent airprox and were, frankly, astonished that the AF 777 continued to land from what we judged to be an extremely unstable position.

wheels up 8th Apr 2022 15:14


Originally Posted by H Peacock (Post 11212446)
Was is not AF who tried to get a 777 airborne with the AP engaged on the ground? Heavy controls interpreted by the PF as a malfunction, so it resulted in a very high-speed abort! 🤔

Air NZ at Narita. Engaged autopilot instead of auto throttle - changed logic after that incident so autopilot can’t be engaged on ground (doh!)

Dropp the Pilot 8th Apr 2022 15:15

Captain Kremin's version is almost certainly correct because the embarrassed and flustered crew immediately darted back to the airport and landed. Maybe hoping nobody had noticed?

If they had genuinely thought they had a flight control problem they would have gone to a hold, done a flight control checklist as a precaution, and re-configured and re-calculated for a Flap 20 landing.

wheels up 8th Apr 2022 15:18

Air France pilot error vs Boeing 777 technical failure - having spent 14 years flying the triple my money would be on pilot error.

Master warning is almost certainly the gear configuration warning, triggered when flap selected to landing position (F30 or F25) and landing gear not down and locked.

Propellerhead 8th Apr 2022 15:27

Could be localizer interference, or even 5G? Wasn’t aware of France being affected by the 5G thing though. They may have asked for a different ILS as they didn’t trust the first one. Programming the wrong approach doesn’t make sense as they flew lined up to the correct runway until it veered off.

eckhard 8th Apr 2022 15:41


Originally Posted by wheels up (Post 11212558)
Air NZ at Narita. Engaged autopilot instead of auto throttle - changed logic after that incident so autopilot can’t be engaged on ground (doh!)

I think AF also tried this at Lagos?

Locked door 8th Apr 2022 16:59


Originally Posted by eckhard (Post 11212572)
I think AF also tried this at Lagos?


Yes they did. They rejected from above V1 and burst a lot of tyres.

suninmyeyes 8th Apr 2022 19:45

Just a suggestion as I have seen a similar thing happen on a 777. One pilot is manually flying and the aircraft is on an intercept heading for the localiser. He asks the other pilot to arm the localiser. The P2 accidentally pushes the button next to it which is the autopilot engage button. The buttons are identical, small and square. The autopilot then engages and will maintain the same heading and descent rate and they will go through the localiser.

The pilot flying then thinks the controls have frozen. It is a busy time for the crew and there is a high workload. The warning you hear is the config warning which is probably because land flap was selected just before the gear had locked down. You then hear the autopilot disconnect warning which is at the point where things probably started to return to normal where the crew realised what had happened. I am not saying this is exactly what happened but from my experience and the noises it would be a plausible scenario.

I too think it is unlikely that there was a major control problem with the 777 and that is was more likely to be finger trouble. However we are all human and it would be wrong to specifically blame Air France. The autopilot engage buttons for both Captain and copilot, the autothrottle engage button and the localiser and approach buttons are all the same small square button. Yes on takeoff at Lagos the Air France crew accidentally pushed the autopilot engage button instead of the autothrottle button and thought the controls had jammed and rejected the takeoff bursting tires. They are not the only airline to have done that and Boeing have changed the logic to stop that particular error being made again.

Klauss 9th Apr 2022 04:58

5 G ?
 

Originally Posted by Propellerhead (Post 11212566)
Could be localizer interference, or even 5G? Wasn’t aware of France being affected by the 5G thing though. They may have asked for a different ILS as they didn’t trust the first one. Programming the wrong approach doesn’t make sense as they flew lined up to the correct runway until it veered off.

Hi, I checked a website. Looks like there is mostly countryside under the 26L approach , at least where the deviaiton happened. Not much 5 G around there.

5star 9th Apr 2022 05:23


Originally Posted by suninmyeyes (Post 11212670)
Just a suggestion as I have seen a similar thing happen on a 777. One pilot is manually flying and the aircraft is on an intercept heading for the localiser. He asks the other pilot to arm the localiser. The P2 accidentally pushes the button next to it which is the autopilot engage button. The buttons are identical, small and square. The autopilot then engages and will maintain the same heading and descent rate and they will go through the localiser.

The pilot flying then thinks the controls have frozen. It is a busy time for the crew and there is a high workload. The warning you hear is the config warning which is probably because land flap was selected just before the gear had locked down. You then hear the autopilot disconnect warning which is at the point where things probably started to return to normal where the crew realised what had happened. I am not saying this is exactly what happened but from my experience and the noises it would be a plausible scenario.

I too think it is unlikely that there was a major control problem with the 777 and that is was more likely to be finger trouble. However we are all human and it would be wrong to specifically blame Air France. The autopilot engage buttons for both Captain and copilot, the autothrottle engage button and the localiser and approach buttons are all the same small square button. Yes on takeoff at Lagos the Air France crew accidentally pushed the autopilot engage button instead of the autothrottle button and thought the controls had jammed and rejected the takeoff bursting tires. They are not the only airline to have done that and Boeing have changed the logic to stop that particular error being made again.

suninyoureyes,

All very plausible, but since when are people not checking their FMAs any more? I just don‘t get it, especially on heavy jets where in reality you only end up after having learned the job and learned from mistakes one made on smaller jets. At AF it takes years to get onto the triple fleet….
And, as was said before, any control or flightcontrols problem would have lead to extensive checklist work after the missed, and that did not happen.
This event should be cleared up asap.




wheels up 9th Apr 2022 06:45


Originally Posted by suninmyeyes (Post 11212670)
Just a suggestion as I have seen a similar thing happen on a 777. One pilot is manually flying and the aircraft is on an intercept heading for the localiser. He asks the other pilot to arm the localiser. The P2 accidentally pushes the button next to it which is the autopilot engage button. The buttons are identical, small and square. The autopilot then engages and will maintain the same heading and descent rate and they will go through the localiser.

The pilot flying then thinks the controls have frozen. It is a busy time for the crew and there is a high workload. The warning you hear is the config warning which is probably because land flap was selected just before the gear had locked down. You then hear the autopilot disconnect warning which is at the point where things probably started to return to normal where the crew realised what had happened. I am not saying this is exactly what happened but from my experience and the noises it would be a plausible scenario.

I too think it is unlikely that there was a major control problem with the 777 and that is was more likely to be finger trouble. However we are all human and it would be wrong to specifically blame Air France. The autopilot engage buttons for both Captain and copilot, the autothrottle engage button and the localiser and approach buttons are all the same small square button. Yes on takeoff at Lagos the Air France crew accidentally pushed the autopilot engage button instead of the autothrottle button and thought the controls had jammed and rejected the takeoff bursting tires. They are not the only airline to have done that and Boeing have changed the logic to stop that particular error being made again.


I’ve always thought that this was an exceptionally poor piece of ergonomic design on the part of Boeing - the A/T switch, A/P switches and APP switch are identical and very close together - it has led to incidents in the past. When a conscious effort is made to differentiate other controls and switches (flaps, gear, strobes, landing lights etc.) what was Boeing thinking here?

In this incident looking at the graphs posted earlier, it appears that the LOC deviation occurred at exactly the same time that the vertical speed started increasing. I’m thinking that possibly the waypoints hadn’t sequenced, they went around due to unstable approach (gear not down? - master warning is definitely gear configuration warning) , and the aircraft attempted to turn back to the previous waypoint, hence the deviation. The deviation commences very close to 1000’ baro altitude - not sure what AF’s stabilised approach altitude is but 1000’ is typical, so this would fit in with that theory.

The only bulletins from Boeing re. 5G relate to interference with radio altimeters - there is no mention of the possibility of LOC interference, it’s most likely a different band altogether. LOC operates in the VHF band, 5G as far as I am aware operates predominately in the UHF band.
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