News ATR-72 turboprop plane crash in Taipei

[steph]

To me it looks like a classic wing tip stall induced by the aileron. I've seen many RC-planes crash this way at our local RC-field. From those videos it looks to me like the right aileron is in full up position during the roll.

I suspect that the pilot was trying to avoid those power lines by turning perpendicular to them. (shortest path to pass over them) Instinctive manoeuvres can be very abrupt compared to planned ones, Seeing those lines during an emergency must have been a frightening sight.

I know there is a danger of fire and electrocution, but wouldn't those lines have slowed it down a bit? Assuming the props didn't sever them, of course.
I'm a bit undecided over what would be worse. Falling straight down at low speed or falling at an angle. I guess the sudden stop at the vertical impact would be bad. At a shallow angle, the energy gets more spread out, you skid etc...the vertical component of the impact is lower etc. Assuming you don't run into a solid cement wall or a rock face or anything like that, you might get away easier that way.

 

[Urwumpe]

I know there is a danger of fire and electrocution, but wouldn't those lines have slowed it down a bit?

Not really - see here about what a jet aircraft did to much stronger cables:

http://en.wikipedia.org/wiki/Cavalese_cable_car_disaster_(1998)

Such a cable car cable has about 65 mm diameter - a lot more than power lines.

 

[C3PO]

I know there is a danger of fire and electrocution, but wouldn't those lines have slowed it down a bit?

A bit of general advice: Avoid Hi-voltage transmission lines at ALL costs. The chance of a better outcome is miniscule.

 

[Astro SG Wise]

FAA investigator just said he lost his engine, and that the propeller was not feathered correctly.

 

[steph]

FAA investigator just said he lost his engine, and that the propeller was not feathered correctly.

Do all investigator have engines? How the hell can you lose an engine? It's not like you can hide it under your bed or something. Alas...with the propeller unfeathered, it might have gone some distance.

 

[Urwumpe]

Do all investigator have engines? How the hell can you lose an engine? It's not like you can hide it under your bed or something. Alas...with the propeller unfeathered, it might have gone some distance.

Problem: Engine 3 missing
Solution: Engine 3 found below starboard wing after brief search.

 

[C3PO]

Alas...with the propeller unfeathered, it might have gone some distance.

A propeller creates a lot of drag unless it's feathered. If the feather mechanism fails you can't maintain altitude, and you will go down.

 

[Cosmic Penguin]

FAA investigator just said he lost his engine, and that the propeller was not feathered correctly.

Do you have a source for that? I don't think the US FAA is involved in the investigation..... (the Taiwan one did, as is the French for ATR and the Canadian for the engine provider Pratt & Whitney)

 

[ex-orbinaut]

Oh, Hell! I hope this is not another of those "Ooops! We shut down the wrong engine" cases...

 

[steph]

So there were such cases? Hmmm..... must Google it.

 

[ex-orbinaut]

So there were such cases? Hmmm..... must Google it.

[ame="http://en.wikipedia.org/wiki/Kegworth_air_disaster"]Kegworth[/ame]

 

[steph]

You'd think the yawing and rolling would give it away. They had an excuse though, with the air conditioning and so on. Can't they see the damaged engine from the cockpit? At the very least ask the flight attendants to look around. You'd think an engine spewing parts, sparks and flames would get people alarmed back in the cabin. Also, engine indicators were all alright? What were they showing? Nominal values? Were they stuck?

Speaking of engine damage, the last flight I was on took place around sunset time. And as we were flying generally due east, the left wing was shadowed by the contrail. You could see the airflow in the running shadow, so to speak, and it almost looked as if something was leaking from the wing. I had a WTF moment for a few seconds, and there some quite scared folks on that side of the plane :lol:

 

[Cosmic Penguin]

Kegworth

Sounds like this was exactly what happened on this flight: it was engine #2 that failed but somehow the crew shut down engine #1. :facepalm:

Source

Edit: Not sure if the report above is correct, but see the FDR recordings for data:

 

[steph]

If they did indeed shut off the right one....seeing as we've seen quite a few idiotic crashes in the last few years, is there the possibility of including human stupidity as a new cause for crashes, as a higher level of human error?
Though I'm being just evil and arrogant here...in crisis situation, sometimes people react strangely. Many would have done the same , or worse.
Who knows, maybe they both failed. Excluding a common cause, the chance of that happening is extremely thin.

 

[ADSWNJ]

Looking at that chart, it sure looks like they realized they had switched off the wrong one, and they restarted it ... only much too late. You can also see that the propellers auto-feather (I'm assuming that this is there Beta traces): i.e.as soon as *both* fuel switches are thrown off together, engine #1 goes to 90 degrees immediately.

So ... plane takes off and gets to 1000 ft, then loses #2 and continues to climb slightly slower, engine #1 loses fuel flow and that's fatal.

 

[RisingFury]

It seems to me that "pilot should always have 100% control" is becoming a fallacy. I think we should hand off emergency procedures to the computer completely. I think at this point, the systems are so complex that the computer might know better what to do than the pilot, given how many sensors it has access to.

 

[ex-orbinaut]

I do not know how to post a stunned silence, really. Just one thing to add regarding this...

If they did indeed shut off the right one....seeing as we've seen quite a few idiotic crashes in the last few years, is there the possibility of including human stupidity as a new cause for crashes, as a higher level of human error?
Though I'm being just evil and arrogant here...in crisis situation, sometimes people react strangely. Many would have done the same , or worse.
Who knows, maybe they both failed. Excluding a common cause, the chance of that happening is extremely thin.

I do not want to make this long winded. There is an "opening" for this sort of muddle up, under stress and short of time, with the current, task sharing procedure between PF and PNF for an engine shut down - procedure as seen fit by the "powers that be", to leave them nameless and let them sleep fitfully at night, where CRM is concerned.

If the procedure seems cumbersome to initial candidates on simulators who first encounter it when transitioning from GA to commercial flying on multis - and sometimes make this very mistake right there on sim - it probably is too cumbersome.

Speedy recovery to those who survived, may they get this behind them with the least possible pain. And again, RIP to those that perished.

 

[C3PO]

It seems to me that "pilot should always have 100% control" is becoming a fallacy. I think we should hand off emergency procedures to the computer completely. I think at this point, the systems are so complex that the computer might know better what to do than the pilot, given how many sensors it has access to.

And when the computer breaks down???
A solution might be to move the engine alarm lights adjacent to the shut-off valves.

On a related note, the decision to remove the flight engineer and put the pilots in charge of what used to be his duties seems less smart with every accident of this kind.

 

[Cairan]

Oh, Hell! I hope this is not another of those "Ooops! We shut down the wrong engine" cases...

From what I've heard, it might be just that... :facepalm:

 

[ISProgram]

It seems to me that "pilot should always have 100% control" is becoming a fallacy. I think we should hand off emergency procedures to the computer completely. I think at this point, the systems are so complex that the computer might know better what to do than the pilot, given how many sensors it has access to.

Um, no. Do you know of [ame="http://en.wikipedia.org/wiki/Air_France_Flight_296"]Air France Flight 296[/ame]? While it might've had its share of "pilot error"-based causes, the computer was a significant cause of the accident as well.

The computer goes by just sensors; it has no idea of the situation. A pilot might have an idea of a situation, or he may not. The computer still is not much better off.

If your pitot tubes ice up at high altitude, the computer thinks "My airspeed is too low" and will tell the pilot. Most often, the pilot will mishandle the situation (ahem, AF447). The aircraft in question is perfectly fine; a AF447-type accident would only occur when the computer is like "This is too much for me" and gives control to the pilot, who then tries to remedy the situation, but then crashes the plane. The computer, a computer in general, would never be able to handle an accident or a anomalous event; that's why many autopilot can only pitch the plan up to 15 degrees (to name one parameter). Once they go beyond that, they'll disconnect. As in, give control back to the pilot.

Computers aren't designed to resolve things like accidents. That's the pilot's job. The pilot might not do a good job resolving, but he's still supposed to. NOT THE COMPUTER.

Also, computers aren't exactly dual redundant. back to those pitot tubes, most planes run their airspeed data off just one. In more than one accident, the pitot tube got up ([ame="http://en.wikipedia.org/wiki/Birgenair_Flight_301"]by a mud dauber wasp once[/ame]) and the computer thought the plane was doing some thing it wasn't really doing, and then acted accordingly to remedy the situation (slowing the plane down because it thought it was overspeeding). The poor confused pilots tried to remedy the situation based on the faulty readings the plane was giving them. The plane stalled and well, crashed.

Frankly, data-checking between three or more pitot units, in where ones that are determined to be faulty are "voted out" (some s/c computers do this) might help prevent an accident of this kind, though it could just as easily cause one like this.

There isn't, and probably will never be, a perfect mix between man and machine that will allow for mistake to not happen. It's impossible, IMO. :2cents: