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bond007
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 1:58 pm

Quoting F9Animal (Reply 26):
I guess we will see what the CVR gives up. Perhaps the crew didn't follow proper procedure on an engine out? I find that hard to swallow, because I am told this subject is covered very well during training and recurrent.
Quoting Navigator (Reply 28):
But unlike you I can easily imagine that the pilots did not follow proper Engine failure procedures. I can also imagine that they lost spatial awareness trying to solve the problem. This leading to the stall we saw.

...and this is the one reason why twins are no safer than singles. They should be of course, and if procedures were followed they would be.

Quoting Navigator (Reply 38):
It somehow bothers me that the airline is looking at its airplane fleet here rather than giving a thought about training issues.

Why? Do you know what caused the accident already apart from suspected engine failure?

Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
LTC8K6
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 2:09 pm

 
bmacleod
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 2:12 pm

CBC news initially reported the TransAsia ATR-72 as a jet before clarifying it as a turboprop. It's happened many times before I guess.
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Backseater
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 2:13 pm

Is there any significance to the word "flameout" used by the pilot in describing the nature of the emergency?
For ATC, the important words were clearly "MAYDAY" and "engine" that imply a real "emergency".
But from an ATR pilot standpoint, is "flameout" typically used to describe any un-commanded engine shutdown?
 
LTC8K6
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 2:17 pm

Quoting BackSeater (Reply 53):
Is there any significance to the word "flameout" used by the pilot in describing the nature of the emergency?

"A turboprop engine is a turbine engine that drives an aircraft propeller."  Big grin

[Edited 2015-02-05 06:18:04]
 
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zeke
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 2:31 pm

Was thinking of their track, maybe jnitially they were going to return to TSA, however changed their minds to go to TPE.
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tguman
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 3:17 pm

Quoting LTC8K6 (Reply 43):
But I think it may just be the way it looks when the elevator moves, as in the pic in post 41.

When watching the slow-motion video posted above, it seems that the elevator is moved for full nose up, then seems to settle back to nuetral right before it hits the bridge. So I'm thinking that this is just the appearance of an openning between the elevator and the HS.
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rfields5421
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 3:21 pm

Quoting zeke (Reply 55):
Was thinking of their track, maybe jnitially they were going to return to TSA,

Is there a visual of the track?

The first news media graphic I saw indicated the aircraft moved initially to the right then apparently started to turn left like it was circling for a landing on the takeoff runway in the opposite direction. I discounted that for two reasons. A 180 return is not often shorter than continuing a pattern return. Also a left turn would put the disabled engine on the inside of the turn. I've always been told by multi-engine pilots don't put a disabled engine 'down' below horizontal. Make the turn where the disabled engine can be kept on the 'high' side.
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Backseater
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 3:31 pm

Quoting LTC8K6 (Reply 54):
"A turboprop engine is a turbine engine that drives an aircraft propeller."  

Thank you. I knew that.
My question was whether an ATR pilot might know more than just "engine died" and therefore try to convey that knowledge in the "nature of emergency". But if "flameout" means "engine died abruptly, cause unknown", then ok!
 
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Navigator
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 4:13 pm

Quoting bond007 (Reply 50):
Why? Do you know what caused the accident already apart from suspected engine failure?


If you put things together like this accident and all discussions about it in this thread and also check this particular Airlines record before this accident I am pretty sure you would feel the same.
747-400/747-200/L1011/DC-10/DC-9/DC-8/MD-80/MD90/A340/A330/A300/A310/A321/A320/A319/767/757/737/727/HS-121/CV990/CV440/S
 
bond007
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 4:22 pm

Quoting Navigator (Reply 59):
If you put things together like this accident and all discussions about it in this thread and also check this particular Airlines record before this accident I am pretty sure you would feel the same.

Not yet I don't.


Jimbo
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trex8
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 4:22 pm

Quoting Navigator (Reply 38):
. It somehow bothers me that the airline is looking at its airplane fleet here rather than giving a thought about training issues.

The regulatory authorities instructed them to carry out the check!

Quoting Navigator (Reply 59):
If you put things together like this accident and all discussions about it in this thread and also check this particular Airlines record before this accident I am pretty sure you would feel the same.

Their record sucks for sure but hitting a truck which was unauthorized to be on a runway when the pilot had ATC clearance is the airline or pilots fault????
 
octubre299
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 4:32 pm

While checking Wikipedia I saw ATR's have been involved in 15 incidents just since 1994, most involving fatalities. Not sure how many units are in operation but sounds to me like they are involved in incidents in a disproportionate way?

Just a hunch.
 
vfw614
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 4:37 pm

I think we are nearing 1.000 ATR deliveries. Given that props operate short haul flights and take-off/landings are statistically the most dangerous parts of a flight, I am not sure if the record is much worse than those of other aircraft.
 
highflier92660
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 5:06 pm

We were watching CNN here in the U.S. with aviation "expert" Richard Quest attempting to explain what initially looked like a classic Vmc roll to the left. I'm not minimizing Mr. Quest's efforts, but the poor guy looks like the late English actor/comedian Terry Thomas, all teeth and saliva flying while loudly blurting out basic terminology of aeronautics like critical angle of attack, chord line, relative wind and "rolling into the dead engine." He really comes-off like an entertainment reporter who just read a How To Fly book before going on-air.

Look for CNN to look for an ATR-72 simulator and some guy to demonstrate the feathering system of a PW127.
 
PlanesNTrains
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 5:17 pm

Quoting vfw614 (Reply 32):
It has been mentioned elsewhere that one of the survivors is a flight attendant who also survived the 2014 crash.

Not trying to make light of it in the least, but there's someone who needs to literally quit while they're ahead.

-Dave
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
HaveBlue
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 5:28 pm

From USA Today:

BEIJING — A pilot of the TransAsia Airways Flight 235 said "mayday, mayday, engine flameout" moments before the propjet banked sharply and crashed into a river, Taiwan aviation officials said Thursday as the death toll grew to 31 with 12 people still missing.

And then, incredibly, they say this:

"Video images of the plane's final moments in the air captured on car dashboard cameras do not appear to show flames as it turned sharply, with its wings going vertical and clipping a highway bridge before plunging into the Keelung River Wednesday"

Seriously? 2 things here.. even if the engines normally produced 'flames', which they do not... the pilot saying "engine flameout" would mean you shouldn't expect to see them. And it would be nice if the reporter knew that when a pilot says that the engine 'flamed out' he means that it lost power.

http://www.usatoday.com/story/news/w...rways-taipei-plane-crash/22842757/
 
rfields5421
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 5:45 pm

Quoting octubre299 (Reply 62):
While checking Wikipedia I saw ATR's have been involved in 15 incidents just since 1994, most involving fatalities. Not sure how many units are in operation but sounds to me like they are involved in incidents in a disproportionate way?

Very bad source for accident 'statistics' on an aircraft.

Much better source - http://aviation-safety.net/index.php

The ATR-42 series shows 30 hull losses - 39 total occurrences - 9 fatal accidents - over 422 aircraft delivered

The ATR-72 series shows 21 hull losses - 30 total occurrences - 10 fatal accidents - over 595 aircraft delivered


The comparison aircraft is the Bombardier/ de Havilland Dash-8 series

Dash 8-100/200 - 11 hull losses - 19 total occurrences - 4 fatal accidents - 404 aircraft delivered

Dash 8-300 - 5 hull losses - 17 total occurrences - 1 fatal accident - 267 aircraft delivered

Dash 8-400 - 5 hull losses - 13 total occurrences - 1 fatal accident - over 439 aircraft delivered


Summary

ATR - 51 hull losses - 69 total occurrences - 19 fatal accidents - 496 deaths (this crash counted as 31) - over 1,017 aircraft delivered
Dash-8 - 21 hull losses - 49 total occurrences - 6 fatal accidents - 128 deaths - over 1,110 aircraft delivered

On the quick view - it looks like the ATR is 'more dangerous' however the bare statistics don't tell the whole story. Both aircraft are proven designs, safe passenger carriers, and widely respected around the world.

The ATR came into operation in 1970, and the Dash 8 came into operation in 1983.
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MEA-707
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 5:59 pm

Quoting rfields5421 (Reply 67):
On the quick view - it looks like the ATR is 'more dangerous' however the bare statistics don't tell the whole story. Both aircraft are proven designs, safe passenger carriers, and widely respected around the world.

The ATR came into operation in 1970, and the Dash 8 came into operation in 1983

No, the ATR only flew in 1984 so that makes them even more comparible.
But while I personally think the Dash 8 is indeed safer, it's comparing apples and oranges. The Dash 8 have their majority flying in countries and with airlines which are the safest in the world, in Canada, Norway, UK, Germany, Austria, Iceland and the USA. The ATR is much more popular in small amounts with airlines in Africa and Asia which are sometimes less safe. I feel the ATRs figures are dragged down by some airlines with bad safety cultures. Transasia crashed 4 of them, that MIGHT be more the problem of Transasia then of the ATR.
nobody has ever died from hard work, but why take the risk?
 
rfields5421
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 6:11 pm

Quoting MEA-707 (Reply 68):
the ATR only flew in 1984

Sorry - misread something on ASN
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747megatop
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 6:28 pm

Hope they find the cause of this crash and take preventive measures. This incident reminds us of Taiwan's notoriously poor safety record.
 
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pvjin
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 6:42 pm

Quoting MEA-707 (Reply 68):

Yes, I'm sure it's irrelevant what aircraft this pathetic airline operates, they are going to crash them anyway. I'm going to be very surprised if the reason behind this particular accident was anything else than pilot error, just like in TransAsia's last three ATR crashes.

At this rate they are going to crash 4 more ATR's by 2030.
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Airspeed772
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:18 pm

Quoting Highflier92660 (Reply 64):

We were watching CNN here in the U.S. with aviation "expert" Richard Quest attempting to explain what initially looked like a classic Vmc roll to the left.
What you see is what you get with blabber mouth Richard Quest. With all the retired experience pilots out there, CNN seem comfortable with Mr. Quest's expertise .
(can any one please show me how to Italicize texts when posting thank you)

[Edited 2015-02-05 11:19:43]

[Edited 2015-02-05 11:29:51]
Airspeed772
 
prebennorholm
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:33 pm

Quoting rfields5421 (Reply 67):
Very bad source for accident 'statistics' on an aircraft.

Question is if there are any good statistics at all. Every event is different. Just have a look at this one:

On 11 October 1999, an Air Botswana captain boarded an ATR 42–320 aircraft at Gaborone Airport and took off. Once in the air, he asked by radio to speak to President Festus Mogae (who was outside the country at the time), Air Botswana's general manager and others. In spite of all attempts to persuade him to land and discuss his grievances, he stated he was going to crash into aircraft parked on the airport apron. After a flying time of about two hours, he performed two loops and then crashed at 200 knots (230 mph) into Air Botswana's two other ATR 42s parked on the apron. The captain was killed, but there were no other casualties. He had been grounded on medical reasons, refused reinstatement, and regrounded until February 2000.

In what sort of statistics does this event belong? Fatal accident? Hull loss? Pilot error? All of them of course. With a 200% bonus in the hull loss statistics.
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Airspeed772
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:36 pm

Quoting Highflier92660 (Reply 64):
[i]We were watching CNN here in the U.S. with aviation "expert" Richard Quest attempting to explain what initially looked like a classic Vmc roll to the left[i]
What you see is what you get with blabber mouth Richard Quest. With all the retired experience pilots out there, CNN seem comfortable with Mr. Quest's expertise .

[Edited 2015-02-05 11:39:28]
Airspeed772
 
hivue
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:39 pm

Quoting Airspeed772 (Reply 74):
[I] We were watching CNN here in the U.S. with aviation "expert" Richard Quest attempting to explain what initially looked like a classic Vmc roll to the left[I].

For some reason if you try to use the html italics tag it inserts a "I" which you then have to delete and type in the "i." (In fact I just had to do it here; is it the font a.net uses?)
Edit: also use angle brackets and not [ ]

[Edited 2015-02-05 11:42:58]

[Edited 2015-02-05 11:43:48]
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motif1
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:40 pm

Quoting Airspeed772 (Reply 72):
(can any one please show me how to Italicize texts when posting thank you)

You use the [ i ] opening and [ /i ] closing tags without the spaces...
Not only is this incomprehensible but the ink is ugly and the paper is from the wrong kind of tree
 
Airspeed772
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:42 pm

Quoting hivue (Reply 75):

Bold and italic options etc. are not user friendly.
Airspeed772
 
Airspeed772
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:44 pm

Quoting motif1 (Reply 76):
You use the [ i ] opening and [ /i ] closing tags without the spaces...

[i]You use the [ i ] opening and [ /i ] closing tags without the spaces...[i]
Just tried it..
Airspeed772
 
motif1
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:47 pm

Quoting Airspeed772 (Reply 78):
You use the [ i ] opening and [ /i ] closing tags without the spaces...[i]
Just tried it..

You didn't use the closing tag [ /i ]
Not only is this incomprehensible but the ink is ugly and the paper is from the wrong kind of tree
 
Pihero
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:49 pm

Trying to get away from the blatant ethnophobia, bias and *the pilot dun it* nonsense.

ENGINE FLAMEOUT
This in itself is a non event, the most practiced exercise in an airline pilot's life.
Get the plane flying, clear the obstacles... Engine relight procedure... End of story.
But it wasn't.
The only problem with that procedure is that one has to select MCT to get the propeller out of feather in the case of an auto feather.
On the numerous pictures, Prop # 1 seems to be rotating, but at a coarser pitch than # 2.

A simple flameout seems to be too... simple.

STALL
Considering the FR24 readouts, it seems likely, but just...
In this condition, there are a few handling problems :
If roll control application of a desired roll to the right :
- On the left wing, with the aileron down, that wing stall will be made worse ( increased AoA due to increased chord curvature)... the stall is accentuated.
- On the right wing, reduced lift due to the spoiler extension and the up aileron movement and increased drag, but not enough to straighten the attitude / roll combination.
The result is in fact even less lift / drag ratio, increasing the downward flightpath.

VMCA
Once again, it should have been controlled quite easily, with just a few degrees of bank toward the right engine... and then the power of that engine should have been enough to accelerate away...
But it didn't happen.

The propellers different pitches seem to tell the story of an unmanageable handling situation : too much power to the right engine and it's a left spiral... not enough power to the right engine and the flight path is downward.
That seems to be the illustration of the last minute videos.
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rwessel
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 7:51 pm

Quoting bond007 (Reply 50):
...and this is the one reason why twins are no safer than singles. They should be of course, and if procedures were followed they would be.

This isn't a light twin (where that particular statistic applies).
 
757gb
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 8:09 pm

Quoting LTC8K6 (Reply 19):

I looked at this several times, and it seems to me that when the HS is over the bridge there is a light pole that gets in the way and distorts the image... but if you stop it a moment later the light seems better and the HS seems normal.


Regarding the fact that the ATR should be able to fly on one engine, has it been established that the left prop was feathered? And if it wasn't, can a single engine overcome the drag of an unfeathered prop and continue to fly safely?
God is The Alpha and The Omega. We come from God. We go towards God. What an Amazing Journey...
 
bond007
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 8:13 pm

Quoting rwessel (Reply 81):
This isn't a light twin (where that particular statistic applies).

...and there are no large commercial singles, but my point still applies. 2 engines are great as long as you are trained what to do if one fails, and apply that training when it does.

Of course, we still have little idea what the cause of this accident was.

Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
rfields5421
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 8:21 pm

Quoting prebennorholm (Reply 73):
In what sort of statistics does this event belong? Fatal accident? Hull loss? Pilot error? All of them of course.

It is listed as a criminal occurrence.
Not all who wander are lost.
 
OMP777X
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 8:35 pm

At this early stage of the investigation and after viewing the video dozens of times, I am now most interested in the "whistleblower" reporting that the pilot demanded an engine inspection after experiencing engine abnormalities on the previous flight (which wasn't performed after all), as was mentioned in the Telegraph report linked above. I think that this will prove to be a key detail in this investigation.

Best,

OMP777X
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WROORD
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 9:03 pm

Quoting Omp777x (Reply 85):
At this early stage of the investigation and after viewing the video dozens of times, I am now most interested in the "whistleblower" reporting that the pilot demanded an engine inspection after experiencing engine abnormalities on the previous flight (which wasn't performed after all), as was mentioned in the Telegraph report linked above. I think that this will prove to be a key detail in this investigation

If this is the case the pilot should have refused to fly.
 
Flaps
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 9:30 pm

Quoting Pihero (Reply 80):
On the numerous pictures, Prop # 1 seems to be rotating, but at a coarser pitch than # 2.

Thank you for verifying my thoughts. That was my first impression and after looking at it several times I have seen nothing to change that first impression. It certainly doesn't appear to me to be fully feathered either. I have experienced two real engine failures in addition to countless training "failures" but have never flown an ATR. Thus I am reluctant to speculate beyond that observation.
 
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PW100
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 9:43 pm

Quoting Navigator (Reply 38):
I agree completely. It somehow bothers me that the airline is looking at its airplane fleet here rather than giving a thought about training issues

It bothers me that you apparently have already decided that it must be poor airmanship that put them in this situation.

From the available video and photos. there is NO evidence this was pilot error. I'll repeat myself:


At around 1000 ft, things were reasonably under control: ground speed around 100 kts. Then at around 1300 ft, ground speed starts dropping. This is countered by reducing altitude and transferring altitude energy into kinetic energy (=speed). They continue to do this until reaching 500 ft. At this point they probably have no other option than to pull up, trying to avoid high-rise buildings (which are plenty around at that point). Rate of descent drops somewhat, at the expense of speed. This continues until they are in an impossible situation: either lack of altitude kills you, or lack of speed (and thus control) kills you.

From an flying point of view, the above doesn't suggest any significant pilot errors to me; pretty much by the book.

The important question is: why was the aircraft (even with engine failure) not able to maintain a positive energy state? From the data and video available at this time, there is not a single shred of evidence to suggest that cause of a pilot error. For instance, it could have been dual engine failure.
Of course, at the same time there is no single shred of evidence that it wasn't a pilot problem.; it could have been an incorrectly handled single engine failure.
But from the video evidence and the stalling itself, there is no way to pinpoint any direction. Therefore it bothers me you are hanging out the crew at this point.

Rgds,
PW100
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OMP777X
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 10:02 pm

Quoting WROORD (Reply 86):

If this is the case the pilot should have refused to fly.

I would tend to completely agree with that. We will have to wait and see what other information related to that is uncovered in the days to come.

Best,

OMP777X
"Happy Flighting!"
 
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PW100
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 10:04 pm

Quoting Pihero (Reply 80):
STALL

Thank you for the summary.

I'd like to add that contrary to popular believe, on modern commercial planes, stall is not an ON/OFF thing; it's a gradual event (that can go very fast of course).

A stall starts usually at the center portion of the wing, and works itself outwards as the stall progresses. This can be achieved by a gradual wing warp-out, where the angle of incidence of the tip is smaller than at the root. It can also be achieved by small changes to aerodynamic profile at the tip zone of the wing. In any case, it is designed into all airplanes.

The idea is to design a wing in such a way that even in fairly progressively developed stall, the wingtips remain fairly stable, keeping the aircraft stable in longitudinal axis, even at *very* high angle of attack.

The importance here is that in this case, based on the videos, the aircraft seemed to be relatively stable until the stall developed into the wingtip zone. This is the violent part of a stall, where one wingtip drops. The dropping will increase AoA even further, thereby further increasing the stall of that wing.
The opposite wing rises, reducing the stall at the tip, increasing lift even further. This will create roll rates that are bizarre, and are impossible to overcome. This is exactly what we saw as the plane crossed the bridge.

With a progressively advanced stall condition (but still stable in longitudinal axis), a very small aileron input could literally be the tipping point.

From the trajectory graph on Aviation Herald, one could assume that the pilot was trying a forced river (crash) landing. This would require a right turn right over the bridge to line up with the river. It could be that this right turn aileron movement, was the tipping point, causing the reverse roll as the left wingtip went into stall.

PW100
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PW100
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RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 10:37 pm

Quoting WROORD (Reply 86):
If this is the case the pilot should have refused to fly.

Really depends on what the alleged engine "abnormalities" were. There are plenty of abnormalities that are perfectly safe to fly.
Many of them are "written up" in the aircraft/engine (electronic) logbook, as they don't require immediate attention.
Some of them are even listed in the MMEL/MEL:

Quote:
A Master Minimum Equipment List (MMEL) is an approved document created
specifically to regulate the dispatch of an aircraft type with inoperative equipment. It
establishes the aircraft equipment allowed to be inoperative under certain conditions for
a specific type of aircraft and still provide an acceptable level of safety. The MMEL
contains the conditions, limitations and procedures required for operating the aircraft
with these items inoperative. The MMEL forms the basis for development and review
of an individual operator's Minimum Equipment List (MEL).
http://www.icao.int/safety/Implement...ibrary/Manual%20-%20MMEL%20MEL.pdf
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
motif1
Posts: 281
Joined: Fri Sep 23, 2005 3:31 am

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 10:45 pm

Shouldn't there be some engine noise from the airplane on the dashcam videos? I could hear the car noises and the thump of the plane hitting the cab/bridge but no prop sound.


*posting the links for easier reference:
https://www.facebook.com/video.php?v=1053519784674205

http://edition.cnn.com/videos/world/...a-crash-dash-cam-video.tvbs-taiwan

M1

[Edited 2015-02-05 14:46:57]

[Edited 2015-02-05 14:48:04]
Not only is this incomprehensible but the ink is ugly and the paper is from the wrong kind of tree
 
Kaiarahi
Posts: 1810
Joined: Tue Jul 07, 2009 6:55 pm

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 10:57 pm

Quoting Pihero (Reply 80):

Thank you, as usual, for the dose of sanity.

Quoting Airspeed772 (Reply 72):
(can any one please show me how to Italicize texts when posting thank you)

Try using the "quote" feature. It's the button at the top right of the post.

Quoting Airspeed772 (Reply 77):
Bold and italic options etc. are not user friendly.

This is actually quite hilarious coming from someone who's telling us how incompetent the pilots were, but can't figure out how to use very basic html code..

Quoting pvjin (Reply 71):
I'm sure it's irrelevant what aircraft this pathetic airline operates, they are going to crash them anyway. I'm going to be very surprised if the reason behind this particular accident was anything else than pilot error, just like in TransAsia's last three ATR crashes.

Since the investigation report on the July, 2014 accident hasn't been published yet, can you enlighten us on how you have determined that it was pilot error.

The originating cause of the 2012 freighter accident was extremely severe icing.

Do you have any more "facts" to support your conclusion.
Empty vessels make the most noise.
 
prebennorholm
Posts: 7101
Joined: Tue Mar 21, 2000 6:25 am

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 11:27 pm

Quoting PW100 (Reply 90):

Very good analysis, PW100. Thanks.

Anyway, on a twin turboprop there is one more thing making it all even more complicated - that is if we assume one good engine at high power and the other windmilling, not dual engine failure.

The good engine "blows" air at increased speed over a substantial part of the wing on its side - the part behind the propeller.

The windmilling propeller substantially reduces the speed of airflow over a substatial part of the other side of the wing.

That adds a further asymmetry issue which makes the whole thing even more complicated.
Always keep your number of landings equal to your number of take-offs
 
frmrCapCadet
Posts: 4428
Joined: Thu May 29, 2008 8:24 pm

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Thu Feb 05, 2015 11:56 pm

PW100 - do you have any idea where on that chart the pilot would have declared an emergency?
Buffet: the airline business...has eaten up capital...like..no other (business)
 
rfields5421
Posts: 6374
Joined: Thu Jul 19, 2007 12:45 am

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Fri Feb 06, 2015 12:03 am

Quoting motif1 (Reply 92):
Shouldn't there be some engine noise from the airplane on the dashcam videos?

No. The aircraft is too far away almost all the time. The only reason you hear the thump is because of how loud it was. At that point the crashing noise is louder than the prop/ engine noise.

Quoting Flaps (Reply 87):
It certainly doesn't appear to me to be fully feathered either.

It appears to me that the prop is still turning and not fully feathered.

However, the nature of electronic shutter/ motion capture used in video cameras is such that things like an aircraft prop never are shown 100% real unless they are stopped and not turning.

One frame of video such as from that camera shoots different parts of the frame at different times. I don't think they will be able to determine anything from the video about the engines/ props. That will have to come from the FDR data.
Not all who wander are lost.
 
trex8
Posts: 5597
Joined: Sat Nov 02, 2002 9:04 am

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Fri Feb 06, 2015 12:07 am

Prelim CVR/FDR data to be released soon??

http://www.taipeitimes.com/News/front/archives/2015/02/06/2003610923

The Aviation Safety Council said that it has finished decoding data on the flight and cockpit voice recorder, adding that details garnered from both black boxes could be released this afternoon.
 
Kaiarahi
Posts: 1810
Joined: Tue Jul 07, 2009 6:55 pm

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Fri Feb 06, 2015 12:22 am

Quoting Pihero (Reply 80):
The only problem with that procedure is that one has to select MCT to get the propeller out of feather in the case of an auto feather.
On the numerous pictures, Prop # 1 seems to be rotating, but at a coarser pitch than # 2.

A simple flameout seems to be too... simple.

I agree. I have C130 time, but have never driven an ATR72.

Are there any ATR-72-600 drivers out there?

I know that when the power is set at TO, there is an automatic feather of a dead engine, a torque uptrim of the live engine to 100% (which can be manually increased to 115%) and auto rudder trim to balance the asymmetric power.

Are these features also present in the CLB detent? At what altitude is CLB detent selected? Will CLB unfeather, or do you need to go to MCT to unfeather and relight? Can you unfeather/relight in CRZ power mode?

PS I know the TO/CLB/CRZ/MCT power modes are available via a rotary switch, but used "detent" for simplicity.

[Edited 2015-02-05 16:27:44]

[Edited 2015-02-05 16:28:59]
Empty vessels make the most noise.
 
orbital
Posts: 12
Joined: Wed Jul 10, 2013 1:06 am

RE: Transasia ATR-72 Crashes In Taipei - Part 2

Fri Feb 06, 2015 12:42 am

I do not as a general matter post. I just read, and absorb the insights of many people that are better pilots than I will ever be, and more knowledgeable about aircraft and their systems than I will ever aspire to be.

However, I am generally apoplectic at the discussion of this most recent accident. The video is possibly the best real time view on an accident in aviation history, and what I see is the following:

1. The port horizontal stabilizer is clearly damaged well prior to the bridge crossing;
2. There is do apparent damage to said stabilizer during the video, suggesting an uncontained
engine failure of some sort sent fragments straight through the empennage assembly (not necessarily just the HS);
2. The pilot attempted to pitch the aircraft up enough to clear the bridge, probably completely unaware of the damage;
3. The lift imbalance on the horizontal stabilizer flipped the aircraft suddenly, unexpectedly, and possibly tragically, relative to other outcomes, although given the geographic specifics in this incident, it is hard to imagine a better or worse outcome.

The aircraft was no doubt near a stall, but not in one. As many people have noted, the ATR can not roll that abruptly as a simple matter of physics without an aerodynamic condition well beyond the intended flight conditions.

If you calculate the roll moment of an aircraft with a partially destroyed stabilizer, including the attendant drag from the clipped/distorted stub on the port side, not to mention any possibly unfeathered (that, I am not able to see well enough to judge) blades on the prop, I am fairly certain that you can create a roll like the one right in front of us.


I'd love to contribute more often, but I'm also wary of the disaster trolls. I just thought this one deserved some more input.

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