Xanadu 16 YMML Blunder

[PoppaJo]

Another one for the collection.

Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation.What happened

On 2 December 2018, an Airbus A330 aircraft departed Melbourne, Vic. on a scheduled passenger service to Kuala Lumpur, Malaysia.

Prior to take-off, the crew noted prevailing weather conditions could be challenging and it was decided that the captain would be pilot flying for the take-off and hand over to the first officer later during climb. The crew received a departure clearance from runway 16 on the BISON 5 Standard Instrument Departure (SID).

As the aircraft lined up, the crew received a report that the last aircraft to land encountered windshear. The captain assessed that it was safe to depart. Due to possible windshear, it was decided to use maximum take-off thrust. The crew reported a normal take-off. Passing 500 ft above mean sea level (AMSL), the captain engaged the autopilot and reduced the power to climb thrust. The climb rate of the aircraft then reduced and the aircraft levelled off around 760 ft AMSL. The crew, suspecting windshear, retracted the flaps and then set take-off/go around (TOGA) power. The ground proximity warning system “DON’T SINK” alert triggered and the airspeed increased beyond the flap retraction speed up to a maximum of 236 kts until the flaps fully retracted.

The aircraft continued to fly level to a position 4 NM from the airport, 400 ft above ground level, with an airspeed of 276 kts. 45 seconds after initial engagement of the autopilot, the captain then disengaged the autopilot and flew the aircraft manually. The captain commenced a climbing turn to follow the SID. During the turn, the angle of bank increased to a maximum of 46 degrees. The aircraft regained the SID, the autopilot engaged, and the flight continued to depart for Kuala Lumpur.

Post-flight, it was determined that altitude (ALT) mode was selected on the autopilot. This caused the aircraft to level off and accelerate. The crew were not aware of this at the time. It is suspected that the captain inadvertently pushed the ALT button which was not detected by the crew. This resulted in the aircraft levelling off at low altitude and allowed the speed to increase, resulting in an airframe overspeed.Safety action

As a result of this occurrence, the operator has advised the ATSB that they have taken the following safety actions:

The details of the event have been shared with all crews to highlight the incident and the need for crews to be autopilot mode aware.

The operator has also conducted further simulator training for the crew involved.About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.



__________
Maximum take-off thrust: the maximum thrust the engine can deliver for a maximum of 5 minutes. (https://www.atsb.gov.au/publications/occurrence-briefs/2018/aviation/ab-2018-133/?fbclid=IwAR2bms75LIpPZnjaknNLcLG4ymL0_ONYA6CTLopesL_JgzvYxf QK74PA8AE#footnote_1)
Take-off go around (TOGA): A setting that can be selected by the pilots to increase power to maximum. (https://www.atsb.gov.au/publications/occurrence-briefs/2018/aviation/ab-2018-133/?fbclid=IwAR2bms75LIpPZnjaknNLcLG4ymL0_ONYA6CTLopesL_JgzvYxf QK74PA8AE#footnote_2)
Altitude (ALT) mode: When ALT mode is selected, the autopilot will hold the current altitude. (https://www.atsb.gov.au/publications/occurrence-briefs/2018/aviation/ab-2018-133/?fbclid=IwAR2bms75LIpPZnjaknNLcLG4ymL0_ONYA6CTLopesL_JgzvYxf QK74PA8AE#footnote_3)

[Berealgetreal]

FMA reading and support at its best.

[machtuk]

Doesn't surprise me at all. The Bus is a clever Plane but not when it's flown by incompetent drivers who are behind the aircraft! I loved flying the Bus but if it's not doing what you expect it to do fly the bloody thing to get it to do what you expect!
It's no different than a B58, power + attitude = perf!!

[Capt Fathom]

power + attitude = perf

A cliche quoted by so many, but used by so few!

[haughtney1]

Rubbish in, rubbish out...and a mindset of if it all gets too hard...A/P engaged. I see the same mindset and methodology when I fly with FOs and Captains from specific countries and cultures.

[Capn Bloggs]

A cliche quoted by so many, but used by so few!
What you meant was "not allowed to be used..."

Reduce the mudslinging... ;)

[wheels_down]

I don’t know what’s more disturbing. In that they flew 400ft level, increasing a/s, flap out, wx around, over suburbia or the fact the ATSB is sidelining it as a ‘brief’ with nothing to see here let’s move along now....

The safety actions, like the many they quote in previous incidents, really don’t seem to be getting across.

[hoss]

Reveal who is receiving the bribe, someone is!

[Ollie Onion]

What is strange is they state they thought they were encountering wind shear so retracted the flaps.

[airdualbleedfault]

Climb thrust at 500 AGL, is this an Air Asia cost cutting measure? How do you over speed the flaps if you retracted them? (yeah I know it's possible to over speed while they're retracting but with climb thrust set?) Retracting flaps and setting TOGA whilst in alt hold, outstanding systems knowledge :ok:

[maggot]

FOs sector.
nah mate, looks challenging (wtf) Ive got this

FFS

[mattyj]

Captain was probably an expat

[maggot]

Captain was probably an expat
Many are from my understanding, not usually westerners if that's the parallel you're trying to make?

[machtuk]

An A330 at 400 ft AGL 4 miles from the airport doing well over 270+ knots would be Airshow material!
The F/O might have done a better job, they often do!

[NinkyNonk]

I'm just an SLF lurker, but I have to say, at an AGL of only twice the length of the aeroplane itself, and covering its own length in less than half a second, I'd be one concerned punter looking out at the window. Then the G loading of the 46 deg turn..

Seems it's a only a matter of time with this mob.. I certainly would never fly with them, and I tell everyone I can the same.

[das Uber Soldat]

Lucky the Captain flew. The FO might have accidentally not nearly killed everyone.

[Potsie Weber]

ATSB segment from the CVR.

CM2: Captain, there is an Airshow at Avalon coming up, that would be spectacular to watch
CM1: Hold my Teh Tarik

[michigan j]

ATSB segment from the CVR.

CM2: Captain, there is an Airshow at Avalon coming up, that would be spectacular to watch
CM1: Hold my Teh Tarik

This wins PPRUNE for the day...

[Karunch]

An interesting insight into what is going on in many flightdecks of carriers visiting our major cities. But the CASA pursuit of Community Service Flights's continues.

[industry insider]

The details of the event have been shared with all crews to highlight the incident and the need for crews to be autopilot mode aware.

Goodness me, that’s innovative. Whatever next?

[StudentInDebt]

Post-flight, it was determined that altitude (ALT) mode was selected on the autopilot. This caused the aircraft to level off and accelerate. The crew were not aware of this at the time. It is suspected that the captain inadvertently pushed the ALT button which was not detected by the crew.Not rated on the 330 but perhaps someone who is can explain how one selects “ALT Mode” by pushing a button?

[maggot]

Not rated on the 330 but perhaps someone who is can explain how one selects “ALT Mode” by pushing a button?

You guessed it
By pushing the alt button

Next question

[StudentInDebt]

You guessed it
By pushing the alt button

Next questionJust so we’re clear, if you press the “ALT button” on the 330 it engages the autopilot in an altitude hold mode rather than the appropriate managed vertical mode?

[t_cas]

Just so we’re clear, if you press the “ALT button” on the 330 it engages the autopilot in an altitude hold mode rather than the appropriate managed vertical mode?


Pressing the ALT button on the FCU commands an immediate level off.

This is independent of whether you are in manual flight or auto flight.

COMMANDS here would mean directs via flight director in manual flight, or indeed AUTOMATICALLY follows the guidance when Autopilot is selected. The Flight Director does work in both manual and auto flight regime.

Mode awareness and indeed the status of the autopilot would appear to be contributing factors in this event.

It is possible it took a while to connect the dots and come to the realization that nobody, nor the autopilot, was flying the aircraft.

[maggot]

Just so we’re clear, if you press the “ALT button” on the 330 it engages the autopilot in an altitude hold mode rather than the appropriate managed vertical mode?

Yes
Why would you expect otherwise?
So you can use it appropriately should you wish. At 400' all engines, probably not but it was inadvertent.

[StudentInDebt]

Yes
Why would you expect otherwise?
So you can use it appropriately should you wish. At 400' all engines, probably not but it was inadvertent.
Because it’s different to how the A320 Alt knob works, you can push that till the cows come home and it won’t level the aircraft if it’s not at the FCU selected altitude or a constraint. I was seeking to understand how the 330 FCU might be different and what outcome the captain might have expected from pushing it when he did.

i’ve now looked it up and see there is an additional button on the A330 FCU for engaging ALT mode, like I say different.

cheers

[AerocatS2A]

Here is someone who has no experience with an autopilot other than the one on the A320! No offence intended, StudentInDebt, but the A320 autopilot panel is quite unusual in not having an ALT button. The ALT button is similar but not identical to pushing the VS knob on the A320. ALT hold captures an altitude rather than just targeting a VS of 0.

[Sparrows.]

i’ve now looked it up and see there is an additional button on the A330 FCU for engaging ALT mode, like I say different.

cheers

Not additional. Replaces the expedite button. FCU panel is identical on both the 320 and 330

[StudentInDebt]

Here is someone who has no experience with an autopilot other than the one on the A320! No offence intended, StudentInDebt, but the A320 autopilot panel is quite unusual in not having an ALT button. The ALT button is similar but not identical to pushing the VS knob on the A320. ALT hold captures an altitude rather than just targeting a VS of 0.Do you know I wondered for 10 years what that HOLD button beneath the Altitude window did on the 757/767 MCP, thanks for clearing that up for me.

As I say, having realised I was missing something, I looked up the answer online myself which then complemented the explanation t_cas gave, and indeed your own once you got the condescension out of the way.

[StudentInDebt]

Not additional. Replaces the expedite button. FCU panel is identical on both the 320 and 330Not all A320s have an expedite button.....

Had enough of this, thanks for the enlightenment, i’ll bow out of the conversation.

[maggot]

Not all A320s have an expedite button.....

Had enough of this, thanks for the enlightenment, i’ll bow out of the conversation.

Well there you go, I've seen a 320 fcu, just assumed it had ALT too
:)

[das Uber Soldat]

Why didn't it go into SRS mode when old mate selected TOGA?

[maggot]

Why didn't it go into SRS mode when old mate selected TOGA?
Looks like toga was on the runway
​​​​​​ needed a toga tap :bored:

[das Uber Soldat]

Looks like toga was on the runway
​​​​​​ needed a toga tap :bored:
yeh but he selected climb/mct at 400 ft, then went back to toga again as the 'windshear' hit. Ie after he pushed alt.

That would have triggered SRS I thought?

[Ollie Onion]

Depends, if they had already retracted the flap then it will not engage GA mode or SRS.

[GA Driver]

If they did in fact retract all the flap (as indicated in the first post) then re-selecting toga after that will not give a mode change (srs/ga trk or nav) it will just give toga.

[das Uber Soldat]

Right, yet they over sped the flap? That wouldn't have happened in CLB detente as it'd be a managed speed target.

So is it safe to assume old mate retracted flap, then immediately selected TOGA (which it would seem works only on flap lever position, not flap actual position), thus negating SRS, yet received the overspeed (which works from actual flap position).

Sound about right? Trying to get my head around it.

[AerocatS2A]

If they selected TOGA then accidentally selected ALT, that would over ride SRS wouldn’t it?

[Veruka Salt]

Without going into the manuals, that's my understanding. Having prematurely selected 'ALT', SRS is de-activated. You can't go back into SRS; the only way to resume the climb would be to "ALT-PULL" into Open Climb, and select an appropriate speed (V2 + 10 etc). Or fly the windshear escape manoevre;)

'Deliberate Action' and FMA confirmation lacking.