TransAsia ATR crash in Taiwan.

[KTF]

Would you pull the fire handle on the failed engine? Seems difficult to get them mixed up assuming this picture is accurate:

[TTmonkey]

I understand from earlier reports that this was a pretty new plane....
any reports on if the pilots had much experience with this type?

[Legend83]

Numpty here, but why would they try and do anything other than climb on one engine using hard rudder then deal with the issue once at a safe altitude?

[saaby93]

http://www.bbc.co.uk/news/world-asia-31162351
Sounds very Kegworth
The Pilot announced on the tannoy which engine he waas hsutting down
the passengers said to cabin crew - inst that the wrong one
cabin crew - it's ok they know what theyre doing
Something like that
Although it wasnt found at fault didnt they 'improve' the instrumentation afterwards?

[RobGT81]

TTmonkey said:

News is saying they lost power to both engines, but attempted a restart on one.

Please tell me they didn't turn an operating engine off, in mistake.

It wouldn't be the first time.

[KTF]

saaby93 said:

http://www.bbc.co.uk/news/world-asia-31162351
Sounds very Kegworth
The Pilot announced on the tannoy which engine he waas hsutting down
the passengers said to cabin crew - inst that the wrong one
cabin crew - it's ok they know what theyre doing
Something like that
Although it wasnt found at fault didnt they 'improve' the instrumentation afterwards?

Where in the BBC piece does it say he announced it to the cabin and crew?

The only mention of flame out was on the mayday call to ATC.

[Eric Mc]

There was an accident a few years ago where the crew of an ATR-72 mixed up their fuel transfer procedures because they were more used to the ATR-42 - which is a bit different.

Were this crew also experienced on ATR-42s?

[Cobalt Blue]

Aviation Herald seems to have a handle on the subject here http://avherald.com/h?article=48145bb3&opt=0

[Eric Mc]

Clearest article yet.

[-crookedtail-]

KTF said:

saaby93 said:

http://www.bbc.co.uk/news/world-asia-31162351
Sounds very Kegworth
The Pilot announced on the tannoy which engine he waas hsutting down
the passengers said to cabin crew - inst that the wrong one
cabin crew - it's ok they know what theyre doing
Something like that
Although it wasnt found at fault didnt they 'improve' the instrumentation afterwards?

Where in the BBC piece does it say he announced it to the cabin and crew?

The only mention of flame out was on the mayday call to ATC.

I think saaby is referring to Kegworth in that respect.

[trashbat]

What potential is there for cross-wiring of the fault system? i.e. that the engine failure was indicated incorrectly

[saaby93]

-crookedtail- said:

KTF said:

saaby93 said:

http://www.bbc.co.uk/news/world-asia-31162351
Sounds very Kegworth
The Pilot announced on the tannoy which engine he was shutting down
the passengers said to cabin crew - isnt that the wrong one
cabin crew - it's ok they know what theyre doing
Something like that
Although it wasnt found at fault didnt they 'improve' the instrumentation afterwards?

Where in the BBC piece does it say he announced it to the cabin and crew?

The only mention of flame out was on the mayday call to ATC.

I think saaby is referring to Kegworth in that respect.

^^ Kegworth ^^
This one>>>
http://avherald.com/h?article=48145bb3&opt=0

aviation herald said:

On Feb 6th 2015 Taiwan's ASC reported that the investigation so far determined from flight data and cockpit voice recorders: the aircraft received takeoff clearance at 10:51Z, in the initial climb the aircraft was handed off to departure at 10:52:33Z.
At 10:52:38Z at about 1200 feet MSL, 37 seconds after becoming airborne, a master warning activated related to the failure of the right hand engine,
at 10:52:43Z the left hand engine was throttled back
and at 10:53:00Z the crew began to discuss engine #1 had stalled.
At 10:53:06Z the right hand engine (engine #2) auto-feathered.
At 10:53:12Z a first stall warning occured and ceased at 10:53:18Z.
At 10:53:19Z the crew discussed that engine #1 had already feathered, the fuel supply had already been cut to the engine and decided to attempt a restart of engine #1.
Two seconds later another stall warning activated.
At 10:53:34Z the crew radioed "Mayday! Mayday! Engine flame out!", multiple attempts to restart the engines followed to no avail.
At 10:54:34Z a second master warning activated, 0.4 seconds later both recorders stopped recording

Edited by saaby93 on Friday 6th February 12:09

[Magog]

Were they trying to restart the no1 engine with the fuel supply shut off?
Do they get it restarted once they realise the fuel supply was shut off, but too late?
Does the engine bleed valve being closed have any impact on being able to restart the engine?

I wonder if having an observer with 16000 hours on the flightdeck had any impact on the pilots reactions.

[saaby93]

It reads to me that the right hand no2 engine reported a fault
They shut down the left no1 engine
Right no2 engine shut down of its own accord
They realisd they now had no engines so tried restarting both
Too late mayday
Should all planes have at least 3 engines?

[KTF]

saaby93 said:

Should all planes have at least 3 engines?

No.

[JuniorD]

saaby93 said:

It reads to me that the right hand no2 engine reported a fault
They shut down the left no1 engine
Right no2 engine shut down of its own accord
They realisd they now had no engines so tried restarting both
Too late mayday
Should all planes have at least 3 engines?

Yeah, just in the case, which happens so frequently, whereby one engine is malfunctioning, and the other has been shut down wrongly, the third engine can try to haul the whole lot into the air at about 250ft/min like an asthmatic geriatric.

[trashbat]

JATOs for everyone!

[Ginetta G15 Girl]

HoHoHo said:

To those of us who may not understand the wiggly lines etc., can you please explain WTF was going on?

I'll try now that I have had time to sit down and write something.

Eric Mc said:

Ssshhh - it's a secret within the brotherhood and sisterhood. They don't REALLY want to explain anything - just demonstrate their detailed knowledge of the subject.

Those of us who don't understand the code are outsiders and unworthy of inclusion.

Oh do grow up!




Looking at the graphical data there appear to be 4 distinct timing points (I have interpolated the timings as best I am able from the limitations of the display).

Note No1 engine is the port, No2 the Starboard.


At 02:52:35 the following happens:

Master Warning Caption No2 Engine Flameout.
No2 Prop starts to go into the Beta range (indicating that it is correctly autofeathering.)
No2 Turbine Inlet Temperature (ITT) falls rapidly (indicating engine shut down).
No2 Overall RPM begins to rapidly drop (NP).
No2 Fuel flow shuts off.
No2 Prop torque begins to fluctuate indicating that the blade angle is rapidly changing (ie autofeather is occurring).
No2 LP Compressor RPM begins to fall (NL).
No2 HP Compressor RPM begins to fall (NH).

At 02:53:05 the following happens:

No1 Power Lever is retarded slightly (PLA - Power Lever Angle reduces), No2 is left at full power.
No1 Turbine Inlet Temperature (ITT) reduces .
No1 Overall RPM reduces slightly (NP).
No1 Fuel flow reduces.
No1 LP Compressor RPM reduces slightly (NL).
No1 HP Compressor RPM reduces slightly (NH).


At 02:53:25 the following happens:

No1 Condition Lever is moved to Fuel SHUT OFF (CLA - Condition Lever Angle).
No1 Prop starts to go into the Beta range (indicating that it is feathering).
No1 Power lever is fully retarded.
No1 Turbine Inlet Temperature (ITT) drops to minimum (idicating engine shut down).
No1 Overall RPM begins to rapidly drop (NP).
No1 Fuel flow shuts off.
No1 Prop torque begins to fluctuate indicating that the blade angle is rapidly changing (ie feather is occurring).
No1 LP Compressor RPM begins to fall (NL).
No1 HP Compressor RPM begins to fall (NH).


At 02:54:19 the following happens:

No1 Condition Lever is moved to the AIRSTART position (fuel shut off valve opens).
No1 Turbine Inlet Temperature (ITT) starts to rise.
No1 LP Compressor RPM begins to rise (NL).
No1 HP Compressor RPM begins to rise(NH).


So, No2 engine fails at around 02:52:35, about 30 seconds later power on No1 engine is retarded. About 30 seconds after that, No1 engine is shut down. About a minute later a relight attempt is started on the No1 engine.



If we couple this with the report of a left wing drop at around the time the No2 failed, as well as with the speed read out from Flight Radar 24 it is apparent that:

The crew mis-identified the failed engine, retarded the live, then shut down the live engine. They then tried to relight the engine they had shut down.

Up to the failure of No2, the rate of climb is around 1500 fpm dropping by about half fom the point of failure until the live engine is shut down. More significantly, the airspeed is decaying to 100 kts when the No2 fails, it then rapidly decays further before stabilising(ish) - looks like the nose was lowered.



This is mere supposition but I would suggest that it is possible that they mis-handled the climbout and possibly stalled the left wing at around the time the engine Master Caption illuminated (accelerated stall). The wing drop led them to believe it was a No1 failure so they shut it down. From that point the inevitible happened.

Edited by Ginetta G15 Girl on Friday 6th February 14:31

[Le TVR]

Thankyou G15

From your explanation, they were achieving relight in the last few seconds. Given the autofeather system, would that start to re-pitch the prop and cause additional asymetric drag that resulted in the port wing dropping suddenly just before impact?

[Eric Mc]

Ginetta G15 Girl said:

Oh do grow up!




Looking at the graphical data there appear to be 4 distinct timing points (I have interpolated the timings as best I am able from the limitations of the display).

Note No1 engine is the port, No2 the Starboard.


At 02:52:35 the following happens:

Master Warning Caption No2 Engine Flameout.
No2 Prop starts to go into the Beta range (indicating that it is correctly autofeathering.)
No2 Turbine Inlet Temperature (ITT) falls rapidly (indicating engine shut down).
No2 Overall RPM begins to rapidly drop (NP).
No2 Fuel flow shuts off.
No2 Prop torque begins to fluctuate indicating that the blade angle is rapidly changing (ie autofeather is occurring).
No2 LP Compressor RPM begins to fall (NL).
No2 HP Compressor RPM begins to fall (NH).

At 02:53:05 the following happens:

No1 Power Lever is retarded slightly (PLA - Power Lever Angle reduces), No2 is left at full power.
No1 Turbine Inlet Temperature (ITT) reduces .
No1 Overall RPM reduces slightly (NP).
No1 Fuel flow reduces.
No1 LP Compressor RPM reduces slightly (NL).
No1 HP Compressor RPM reduces slightly (NH).


At 02:53:25 the following happens:

No1 Condition Lever is moved to Fuel SHUT OFF (CLA - Condition Lever Angle).
No1 Prop starts to go into the Beta range (indicating that it is feathering).
No1 Power lever is fully retarded.
No1 Turbine Inlet Temperature (ITT) drops to minimum (idicating engine shut down).
No1 Overall RPM begins to rapidly drop (NP).
No1 Fuel flow shuts off.
No1 Prop torque begins to fluctuate indicating that the blade angle is rapidly changing (ie feather is occurring).
No1 LP Compressor RPM begins to fall (NL).
No1 HP Compressor RPM begins to fall (NH).


At 02:54:19 the following happens:

No1 Condition Lever is moved to the AIRSTART position (fuel shut off valve opens).
No1 Turbine Inlet Temperature (ITT) starts to rise.
No1 LP Compressor RPM begins to rise (NL).
No1 HP Compressor RPM begins to rise(NH).


So, No2 engine fails at around 02:52:35, about 30 seconds later power on No1 engine is retarded. About 30 seconds after that, No1 engine is shut down. About a minute later a relight attempt is started on the No1 engine.



If we couple this with the report of a left wing drop at around the time the No2 failed, as well as with the speed read out from Flight Radar 24 it is apparent that:

The crew mis-identified the failed engine, retarded the live, then shut down the live engine. They then tried to relight the engine they had shut down.

Up to the failure of No2, the rate of climb is around 1500 fpm dropping by about half fom the point of failure until the live engine is shut down. More significantly, the airspeed is decaying to 100 kts when the No2 fails, it then rapidly decays further before stabilising(ish) - looks like the nose was lowered.



This is mere supposition but I would suggest that it is possible that they mis-handled the climbout and possibly stalled the left wing at around the time the engine Master Caption illuminated (accelerated stall). The wing drop led them to believe it was a No1 failure so they shut it down. From that point the inevitible happened.

Edited by Ginetta G15 Girl on Friday 6th February 14:31

Good, detailed explanations from people like you (like the above) are appreciated by people like me. The problem is when people like you resort to acronyms, abbreviations etc which make it seem like you are showing off and not trying to inform. When you write like that, are you TRYING to exclude others or do you genuinely think that we all understand what they mean?

It's not a question of me growing up.

It's a question of perhaps you being a bit more thoughtful of others.