ATR down in Taipei

[Minuteman]

Just curious. Looking at the data, what makes it so impossible to figure out that the crew shut down the wrong engine and flew a flyable airplane into the ground. I see posts like this and scratch my head. It's blatantly obvious what happened here looking at the FDR data. The crew screwed up, shut the wrong one down after the other one failed, and crashed. Am I missing something? What other data needs to be/will be looked at that changes that?

For one, that's a picture from Twitter that only looks authentic. It has not necessarily been reviewed by anyone who knows what they're doing and says yes, this appears to be free of significant errors or interruption in continuity, and different indications correlate well with our other understanding of events.

For two, did the crew mistakenly turn off a good engine? Is "CLA fuel shut off" an indication of a switch or valve position? Was there some sort of electrical error, where (say) pulling a fire handle for one engine somehow sent a signal to both flow control valves? An on-site investigation of the wreckage may answer that.

Was there a situation where opposing forces were being put on the rudder pedals by the crew, causing a false "dead foot, dead engine" feeling? Pedal forces are not present in the those traces I shared.

They incrementally pulled the PLA on the good engine before shut down. Why? Was there something going on with the airframe or engine parameter presentation? Did a flock of birds cause both the engine trouble and also somehow inhibit the crew from addressing the troubled engine. It's good that there is likely a CVR (that we have not heard) that can answer those questions.

There's no need to declare it's obvious what happened; that's the whole point of a procedural investigation. Gather information, draw conclusions, present in an organized form.

 

[Baronpilot244]

Can any ATR drivers post the engine failure after takeoff checklist items - might give an insight into what these guys were trying to accomplish...

Bp244

 

[Autothrust Blue]

For one, that's a picture from Twitter that only looks authentic. It has not necessarily been reviewed by anyone who knows what they're doing and says yes, this appears to be free of significant errors or interruption in continuity, and different indications correlate well with our other understanding of events.

For two, did the crew mistakenly turn off a good engine? Is "CLA fuel shut off" an indication of a switch or valve position? Was there some sort of electrical error, where (say) pulling a fire handle for one engine somehow sent a signal to both flow control valves? An on-site investigation of the wreckage may answer that.

Was there a situation where opposing forces were being put on the rudder pedals by the crew, causing a false "dead foot, dead engine" feeling? Pedal forces are not present in the those traces I shared.

They incrementally pulled the PLA on the good engine before shut down. Why? Was there something going on with the airframe or engine parameter presentation? Did a flock of birds cause both the engine trouble and also somehow inhibit the crew from addressing the troubled engine. It's good that there is likely a CVR (that we have not heard) that can answer those questions.

There's no need to declare it's obvious what happened; that's the whole point of a procedural investigation. Gather information, draw conclusions, present in an organized form.

WHAT happened is obvious: there is a smoking crater. The WHY, as always, is the far more interesting and much more difficult to determine part.

 

[Pilot Fighter]

There's no need to declare it's obvious what happened...

Has anyone made such a declaration?

 

[sweeps]

Has anyone made such a declaration?

Just curious. Looking at the data, what makes it so impossible to figure out that the crew shut down the wrong engine and flew a flyable airplane into the ground. I see posts like this and scratch my head. It's blatantly obvious what happened here looking at the FDR data. The crew screwed up, shut the wrong one down after the other one failed, and crashed. Am I missing something? What other data needs to be/will be looked at that changes that?

I think this is what @Minuteman was referring to

 

[sweeps]

Ahhh, blatantly obvious.

Indeed

 

[deadstick]

Indeed

Is that along the same lines as "strenuously objecting?"

 

[Pilot Fighter]

Is that along the same lines as "strenuously objecting?"

Clear. I mean, crystal clear.

 

[knot4u]

... or tired.

Has there been any info released on the previous few days for the crew regarding their schedule? Could be interesting.

 

[gliderboy]

You can't train experience.

 

[cmhumphr]

You can't train experience.

Yes and there was plenty of experience in that flightdeck.

 

[GypsyPilot]

Yes and there was plenty of experience in that flightdeck.

The question is, what kind?

 

[mikecweb]

 

[jcremy]

Can any ATR drivers post the engine failure after takeoff checklist items - might give an insight into what these guys were trying to accomplish...

Bp244

If it auto feathers and up trims (automatically gives you an extra 10% on the good engine) you don't do squat to acceleration height then level off for a bit to get up the speed, raise the flaps and get the climb going. Then you start touching levers after verifying the bad engine. If the the auto feathering system works properly, there is no reason to touch the levers until you are safely climbing.

And to the other question, no, moving the power lever does not affect the auto feathering except for arming or disarming the system. But if it's already feathered the condition lever controls the pitch of the prop and fuel flow.

 

[🦈💜]

So are we still thinking Vmc rollover, or are we thinking ... quarter snap roll to a 45° down?

Dat AoA, bro. :/

-Fox
(I feel like @Boris Badenov today for some reason ...)

 

[JordanD]

I missed it, I think they should have replayed it one more time.

 

[🦈💜]

Sometimes I think under-reacting is underrated.

 

[z987k]

If it auto feathers and up trims (automatically gives you an extra 10% on the good engine) you don't do squat to acceleration height then level off for a bit to get up the speed, raise the flaps and get the climb going. Then you start touching levers after verifying the bad engine. If the the auto feathering system works properly, there is no reason to touch the levers until you are safely climbing.

And to the other question, no, moving the power lever does not affect the auto feathering except for arming or disarming the system. But if it's already feathered the condition lever controls the pitch of the prop and fuel flow.

So in other words it's like every other transport category airplane ever?

 

[Tiptank]

Does the ATR do any kind of "auto rudder trimming" through the YD or something in the event of an engine failure? I'm just a recip twin guy, so the whole bringing the power back on the good engine thing without noticing the obvious resultant "seat-of-the-pants" warning signs is kind of puzzling.

The FDR chart is interesting, but I'm not too confident in my interpretation of it. It does look like to me that they brought the power back on the good engine rather slowly, or incrementally, rather than just chopping the lever? I guess that might make the yawing clues less obvious? At any rate I can't imagine pulling ANY levers BACK in that situation in a Tprop assuming the autofeather worked as intended. Strange.

 

[scooter2525]

@ChasenSFO translation please.