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-   -   Smartlynx A320 runway excursion EETN 28.2.2018 (https://www.pprune.org/rumours-news/605990-smartlynx-a320-runway-excursion-eetn-28-2-2018-a.html)

Lascaille 20th Mar 2018 07:39

And if we continue the train of thought and suppose that the trainee for some reason (seizure!) accidentally pushed and held the takeover button on their stick - or that their sidestick suffered a malfunction such that their takeover button became permanently pressed - then even in such a case the TRE's sidestick would regain priority once the TRE pushed their 'takeover' button, as the last discrete button press (by which specifically we mean a transition from unpressed to pressed, not a continuation of the pressed state) assigns priority.

Thusly a wedged/locked sidestick with a wedged/locked priority button is still overridden with any single press of the priority button on the other stick at any later point in time.

What could not be overridden, I believe, would be 'rapidfire' of the priority button on the trainee's side.

I could only see that type of input happening - in the remotest of chances - if the relevant wires to the button had become loose or fractured and were intermittently making and breaking contact as the wire moved.

I suspect also this can be ruled out as I would imagine that the sidestick buttons are double-pole-changeover type, with a button press simultaneously closing one circuit and opening another? I imagine this knowing that even the brake pedal interlock switches on economy cars work this way. But I do not know for sure!

Volume 20th Mar 2018 08:42

For me this looks like a much, much simpler scenario. And it did happen before.
If you do not apply full thrust for the go-around (and you do not need this for an empty aircraft on training flights) you do not trigger the TOGA logic, your autopilot still tries to land the aircraft.
"the aircraft suddenly failed to respond to any inputs and shortly afterwards both engines lost power" This is what you expect from an active autopilot which you ask to land the aircraft...
Computers do not do what you want them to do, but what you ask them to do... Learn the language of the computer if you want to use it. To initiate a go-around you have to advance the throttles all the way to the TOGA detent. If you don´t, your aircraft behaves strangely and won´t go around the way you want it to.
This accident is probably the same issue as the 777 in Dubai, just on a different type of aircraft and hence a different type of fingertrouble initiating a go-around (or not initiating it...).

FlightDetent 20th Mar 2018 09:01

^^^ rubbish

Volume 20th Mar 2018 09:09

https://flightsafety.org/wp-content/...y-First-23.pdf
https://www.atsb.gov.au/media/793232/ao2007044.pdf

Intrance 20th Mar 2018 10:59

Not sure about the logic of that 'simpler' scenario... autopilot trying to fly the plane on a takeoff roll? That would mean autopilot engaged on the ground before takeoff? I'm pretty sure they don't do autolands during the basetraining so I see no logical reason why the autopilot would have any kind of control during a touch & go...

And the first part of the thrust lever movement is still direct control in the Airbus, correct? So even if you don't move them all the way to the TOGA detent, you should still get a bunch of thrust. Perhaps the logic doesn't change but there shouldn't be any autopilot engaged sooo....

But I don't fly the Airbus so maybe I lack some knowledge there. Your simpler scenario just doesn't make any sense to me, perhaps my type is too simple :rolleyes:. The two PDFs you linked also don't really seem relevant as they treat go-arounds performed during the approach and from autopilot engaged situations.

wiedehopf 20th Mar 2018 12:27

@intrance

could still influence the FD bars right?

so yes they would gain speed in the MCT setting as ATHR becomes inactive but if they go back to the CLB detent the ATHR kicks back in (see the second pdf and scroll to the nice diagram).

a trainee flying the FD bars could then produce the strange behaviour of the plane not wanting to climb. dual input would sound as described but maybe it wasn't recognized properly as described in other posts.

and as for the second pdf:
the PIC had more than enough thrust and speed to climb but he didn't. (in the diagram you can see the airspeed being quite high and they are still descending)
so even as he was controlling the aircraft he was probably following the FD.

even the training captain taking control might have fallen for this stuff even if he shouldn't have.

too bad FDR data is not just made public at the start of the investigation now that would reduce the speculation on defects and human factor not what actually happened :)

Lascaille 20th Mar 2018 13:31


Originally Posted by wiedehopf (Post 10090284)
too bad FDR data is not just made public at the start of the investigation now that would reduce the speculation on defects and human factor not what actually happened :)

It always seems ghoulish and disrespectful to the dead to speculate too wildly about human failures, mistakes and suchlike in an incident which claims lives, especially the lives of the flight deck crew.

In a bloodless incident like this I quite enjoy the chance to harmlessly speculate, bounce scenarios off people and learn some systems knowledge.

Intrance 20th Mar 2018 13:37

If you have just made a successful landing in the A320, and you don't set proper TOGA power, what mode does the automation revert to? What will the FD show? Will it be approach mode and basically only show a localizer perhaps? I'd doubt anyone will try to fly a FD with the vertical guidance showing level or just completely missing for a takeoff roll...

The scenario just sounds like a bit of a reach honestly. But who knows. I'd still put my money on some sort of technical issue or perhaps the dual input issue.

FlightDetent 20th Mar 2018 19:43

Volume, thank you for the links, my favourite would be this one: https://www.bea.aero/docspa/2012/f-z...f-zu120313.pdf.

Neither of the three has any relevance to the situation in Tallin, I believe. Sorry for my brevity in the morning. The bolded text below is yours.

If you do not apply full thrust for the go-around It is was not a go-around, but a touch-and-go. In the context a seriously different thing.

an empty aircraft on training flights standard base-training load as per Airbus training manual is +10t ballast, not empty

full thrust for the go-around (and you do not need this You're starting the "-and-go" part of the show after some essential re-configuration from around 90 kts. with maybe no more than 900 mtrs left. The only way to reasonably assure T/O perf is to go full TOGA, no middle ground.

not trigger the TOGA logic, your autopilot still tries to land the aircraft no, it was not engaged for the preceding landing.

"the aircraft suddenly failed to respond to any inputs and shortly afterwards both engines lost power" This is what you expect from an active autopilot which you ask to land the aircraft... Without attacking the quote's accuracy - which may be prudent later: not on Airbus. To make an input is to pull, and pull on the stick disengages the A/P. I am not saying the aircraft remained responsive, but if tragically so then it was not a result of A/P engaged.

Also there would be no leftover flight directors.

FlightDetent 20th Mar 2018 19:49


Originally Posted by Intrance (Post 10090360)
successful landing in the A320, and you don't set proper TOGA power, what mode does the automation revert to? What will the FD show?

Nothing engaged, nothing armed. Empty.

Elephant and Castle 20th Mar 2018 20:37

If the AC had remained in Flare mode a pitch down order would be introduced and the behaviour and feel of the flight controls would be very different to what a trainee would be used to. Any release of the side stick, before flight mode has resumed, would mean an immediate pitch down. This would be compounded if the attitude at 50`on the approach was very nose down, as that is the reference point the system uses for the flare manoeuvre.

An unstable approach path with a steep nose down attitude crossing 50´followed by a hard landing with a failure of the air ground sensing logic would have prevent the aircraft flight control laws transitioning to ground mode. At "rotate" the trainee would have pulled the side stick to start the rotation, if he then released the pitch input on the side stick (as in a normal T/O) the aircraft would have pitched down and maybe made contact with the runway. If we combine this with an over-keen "positive climb - gear up" call the aircraft might have contacted the runway with the gear in transit. Leading to damage of the gear doors and engine contact with the ground.

tubby linton 20th Mar 2018 20:48

If there had been a technical problem Airbus would have issued a notice to operators by now.Has anybody heard of one being issued?
The last time I did base training in the aircraft the brief was after touchdown the trainer would reconfigure the aircraft, whilst the trainee kept it straight. Once this had occurred the call was to stand the thrust up , and when stable apply TOGA thrust. Did the trainee not apply Toga before the end of the runway?

Volume 21st Mar 2018 09:20


Did the trainee not apply Toga before the end of the runway?
That´s what I suspect.
And this would not be a "technical problem", but mishandling of the aircraft. Airbus did issue several publications to clarify the use of the throttles and the TOGA logic if no full power is required.


It is was not a go-around, but a touch-and-go.
Is it yet clear, how much it really touched? It may have kissed the ground, but not enough to trigger the ground logic. Excessive speed was mentioned in the reports.
The FDR will tell.

macdo 21st Mar 2018 10:34


Originally Posted by tubby linton (Post 10090852)
If there had been a technical problem Airbus would have issued a notice to operators by now.Has anybody heard of one being issued?
The last time I did base training in the aircraft the brief was after touchdown the trainer would reconfigure the aircraft, whilst the trainee kept it straight. Once this had occurred the call was to stand the thrust up , and when stable apply TOGA thrust. Did the trainee not apply Toga before the end of the runway?

That's how we do it. Is it possible that the trainer got distracted and they tried to get airborne with the TL's just stood up? Hard to believe as CM1 should have put their hands on the TL's for the remainder of the take off run and someone should have been reading the FMA. Even if the TL's were only pushed to CL detent I would have thought there would be enough power to get the thing airborne in an empty aeroplane, but I guess that if they were not and the thing was struggling to launch an early Gear Up could have squatted it back down on to the moving gear. Going to be a fascinating story when it all come out.

andrasz 21st Mar 2018 10:55

Many moons ago I witnessed a 73' do a derated takeoff with a slight (1-2 kts) tailwind component. FO instinctively selected gear up as soon as mains left the ground, just as a slight increase in tailwind caused the aircaft to slowly sink. Full thrust was applied but with the time lag the plane settled back on the runway with gears retracted, sliding on the engine pods and the rear fuselage for a few seconds until it climbed away. Crew were unaware of the ground strike and continued takeoff, ony to return after the aircraft failed to pressurize. Interestingly the engine pods had minimal damage (with no damage to the engines themselves) but the fuselage needed extensive repairs.

FlightDetent 21st Mar 2018 21:33

macdo / tubby: the airbus drill is bit different. Stand up first, then conf change followed by TOGA. (checked the book right now).

Volume: the problematics explained so well is PLENTY of power, but automatics / guidance still aimed to land. Does not apply here. Their automatics were off by the nature of the landing done, but not enough thrust... The "touch-and-go" is "land, then roll quite a bit, and takeoff": no way to fool WoW there. (red herring anyway)

tubby linton 21st Mar 2018 22:17

Do you have a reference Flightdetent?
We always did it as I described , and recounted here.
https://assets.publishing.service.go...OZBY_07-14.pdf

FlightDetent 21st Mar 2018 22:42

These are leaked into public domain (noted: yours is more recent - useful read BTW!)

http://elearning.onurair.com.tr/webc.../BSTR_A320.pdf
http://cbt.brusselsairlines.com/webc...E-TRAINING.pdf
https://www.cockpitseeker.com/wp-con.../fctp/fctp.pdf

ShotOne 23rd Mar 2018 07:54

If the thrust levers had been stood up but then not advanced to TOGA it would likely have produced the flight path that occurred. But can anyone suggest a technical failure or failures which would fit in with what the operator has said happened?

FLEXJET 27th Mar 2018 06:15

What about the possibility of a double ELAC failure at the wrong time and side sticks U/S?

A4 28th Mar 2018 06:23

.....the chances of which are infinitely small! What about aliens......:hmm:

macdo 28th Mar 2018 08:17

While not supporting any particular failure in this incident,with Airbus you can never discount the impossible. Years ago, we were told that it was impossible to lose all 6 screens, but one of ours did over the Bay of Biscay. All ended happily, eventually Airbus came up with a 'why' this happened when it was thought impossible.

andrasz 27th Apr 2018 19:53

Taxied past the aircraft yesterday, still sitting on the ramp where it was parked right after the accident, with engines covered and gear doors (at least what remains) hanging. Does not look like it is going anywhere anytime soon.. W/O?

ShotOne 28th Apr 2018 08:21

Two months down the line after, allegedly, an exceptional combination of sudden technical failures caused a near-catastrophe in s widely used passenger jet. Anyone care to comment on this inexplicable deafening silence?

tescoapp 28th Apr 2018 09:09

There is one bloke that does accident investigation in Estonia with I think another two helping neither of which have any high level engineering qualifications. There is no real skill set in country for the systems analysis. Normally there is not a lot of on going incidents to work on hence everything is probably getting farmed out. Its not like the UK where there are several investigators full time with multiple full time resources to call on.

The bloke is probably still getting his head round how an airbus works.

What's happened to the airframe?

Intrance 28th Apr 2018 19:30


Originally Posted by andrasz (Post 10132041)
Taxied past the aircraft yesterday, still sitting on the ramp where it was parked right after the accident, with engines covered and gear doors (at least what remains) hanging. Does not look like it is going anywhere anytime soon.. W/O?

It has actually been towed between stands and there is activity around the plane fairly often with doors open, people moving in and around. It is still in poor state though, with the soot still on the engines from the apparent fire(s).

Wonder if the trainees have been cleared for duty again already, Smartlynx was doing a bunch of base training yesterday or the day before.

andrasz 6th Jun 2018 21:39

Taxied past it again yesterday, same position, exactly the same state as five weeks ago.
Saw another white tail 320 reg XY-AGO at a gate, apparently leased in from Myanmar Airways to fill the capacity gap for the summer charters.

andrasz 29th Sep 2018 19:48

The aircraft is still parked where it was four months ago with hanging gear doors, but now sans engines. Given the long inactvity it could be a w/o.

ShotOne 2nd Jan 2019 08:39

Well it’s 2019 now, no further official information about the cause of what now appears to be a hull-loss. Any news?

Sidestick_n_Rudder 2nd Jan 2019 09:16

FWIW, it took the Germans 7 years to investigate the SIA MUC incident, so don’t be too harsh on Estonian investigators...

Intrance 2nd Jan 2019 09:22

Definitely hull loss. Plane was purchased by Magnetic MRO I believe, and parted out with the main fuselage being transported away from the airport on the 14th last month. Otherwise no news on the report or investigation that I know of. I think the most recent English language report took them a little over a year to complete and was about a decompression of a small business jet. This crash landing of the Smartlynx could be considered a bit more complex and probably will take longer, but who knows, perhaps something will pop up next month.

Blurry pic of the fuselage being removed:

https://cimg5.ibsrv.net/gimg/pprune....aad7108e9.jpeg

FlightDetent 25th May 2019 21:04

Latest FCTM revision comes with a new paragraph. In case of an in-flight failure during circuit training, the next take-off should be (after a full stop, presumably) considered a new dispatch with release as per MEL if required. Any leads this is connected?

FreezingDrizzle 3rd Jun 2019 02:10

As far as I understand, if there are failures during cirquit training, the MEL should now be applied also after each touch and go, not just full stop landing. The final report will most likely reveal that this is related.

giggitygiggity 3rd Jun 2019 23:32


Originally Posted by FreezingDrizzle (Post 10485140)
As far as I understand, if there are failures during cirquit training, the MEL should now be applied also after each touch and go, not just full stop landing. The final report will most likely reveal that this is related.

Really? If I go around, must I apply the MEL before I land again? If I get a no-go item such as an aircraft that will no longer compress due to a tail strike, what am I supposed to do? The MEL can be used for information, but not procedures to be followed as they're designed for use on the ground. Some procedures might ask you to pop cbs, those procedures are not approved for use in flight.

FlightDetent 4th Jun 2019 10:21

GG you are reading it all wrong. Me guilty as charged, things lost in translation of my post as well.

Your example is good, just do not put GA into the explanation. Should you have a tailstrike during circuit touch and go training, surely you just come back. And that is when the new wording from Airbus comes to rule. After that touchdown we are told to stop and apply new maintenance dispatch release, including MEL relief and restriction if possible or required. Kind of a no brainer huh, nobody would continue the circuits with a scratched tail.

Well, for some gremlins it might not be as clear cut and immediately obvious. BRK SYS 2 fault? Hot Air fault?

Now, most likely as a result of a human factors cluster flop, a new sentence is introduced to clarify that a fault during circuits ends the exercise with the next touchdown, and once stopped the ground phase MEL restrictions would apply.

It seems related to this accident, hence I revivied the topic.

FreezingDrizzle 4th Jun 2019 20:16


Originally Posted by giggitygiggity (Post 10485854)
Really? If I go around, must I apply the MEL before I land again? If I get a no-go item such as an aircraft that will no longer compress due to a tail strike, what am I supposed to do? The MEL can be used for information, but not procedures to be followed as they're designed for use on the ground. Some procedures might ask you to pop cbs, those procedures are not approved for use in flight.

As already pointed out, this FCOM revision was related to cirquit training, not to normal revenue flights. In cirquit training this means that you cannot perform a touch and go (or a full stop and a new take off) IF you have new failures and IF you haven’t applied the MEL. If, say, an ELAC fails during cirquit, instead of a planned touch and go, you must now make a full stop landing, apply the MEL and then take off again if allowed by MEL. Obviously if you are airborne, you’ll handle your ECAM actions the same as always.

compressor stall 5th Jun 2019 08:44

The FCTM revision came out from Airbus in Dec 18 (and obviously took time to filter down to line pilot level). I've been told there's a link.

tubby linton 3rd Nov 2019 23:00

Simon H has written up the accident report.What a horrible situation the crew found themselves in.
Accident: Smartlynx A320 at Tallinn on Feb 28th 2018, runway excursion after bad touch and go due to elevator control completely lost

macdo 3rd Nov 2019 23:47

Jeez, that was a real Halloween read just before bed. Aviate, Navigate, Communicate saves the day.

Capn Bloggs 3rd Nov 2019 23:58

Crikey! My head really hurts after reading that...


SEC design flaw allowing for a single event, the left landing gear temporary decompression, to cause the loss of pitch control by both SECs.
Tut tut!


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