Transasia Atr 72 Down In Taiwan

[Guest]

Play the video again and freeze frame it in the 6 - 8 second range. Feathered?

Well the blades are definitely more coarse looking than on #2. Perhaps not fully feathered. The initial track would lead one to think the #2 could be the culprit but it's hard to know for sure. What heading did the airplane actually come off the runway on, after the malfunction? The final roll to the left indicates the #2 was developing the power.

On the Q400 when the blades are feathered with no engine torque (ie: a flameout with an Autofeather) the RPM will generally go to zero.

This crew said "engine flameout" in their radio call (I believe). Based on that, if the Autofeather operated correctly, I would expect the RPM of the prop to be near zero in the video- or really close to it. There are several scenarios of an engine failure or malfunction that can be presented to turboprop drivers. Engine failure recognition is something we train annually, and it can easily fool some. Emphasis is on whether or not there is drag present (among other scenarios; fire, prop overspeed (that can be a handful if mis-identified), oil pressure loss etc). It's a critical time to be doing the right actions.

There was questions about the autofeather importance. On the Q400, there is no MEL relief. On the Classic DH8 there is. Big difference is that the Q has FADEC and PEC, so the Autofeather is an integral part of that. However I can tell you that the Q will happily climb out with a "failure/negative feather" to whatever altitude you're going to (in the sim at least). The DH8 not so much. But I don't know how the ATR600 would handle in that situation. Perhaps the video shows us?

On listening again to the Mayday call, I'm not convinced the word "engine flameout" was used- it sounds like it could easily be "engine failure". That, to me, opens up a whole multitude of possibilities.

Don, what kind of transparency can we expect from the Taiwan investigators? Lots of questions that have answers were carried off in that clear plastic case yesterday.

[Guest]

PS- unrelated, but here is a fairly well written article as a direct comparison between the Q400 and the ATR600 if anyone is interested.

http://theflyingengineer.com/aircraft/proud-to-fly-a-turboprop-q400-vs-atr72/

[Seeker]

further to that, there are stories today crediting the pilot with taking action to avoid hitting apartment buildings which would have doomed everyone on board and likely killed people in their flats.

I wouldn't place much (or any) value on those stories. No pilot would ever go through the thought process - "I'm going to steer away from the buildings to prevent more deaths in the buildings". A last second effort to point towards the lowest/softest obstacle out of self-preservation maybe but that's all.

[DEFCON]

I’ve been looking for data on ATR 72 –600 single engine climb gradients etc., but haven’t had any luck. Anyone?

It would be nice if it was found that the pilots accepted their fate in an effort to avoid buildings etc and save the residents, but I think it’s way to early to come to that conclusion Dagger. Besides, the pilots would appreciate how short their time would be if they went headlong into a building.

I’m curious to understand the reasons behind the descent from an altitude at a distance from T/O that should have allowed for continued safe flight.

If the aircraft had been loaded with contaminated fuel, perhaps one quit and moments later the other stopped delivering adequate power, which left the crew unable to even maintain altitude? I don’t know, but if you overlay the track of the aircraft on Google Earth images, it does kind of look like the pilots may have accepted the fact they were going down and were making a heroic attempt to make the river? Avoiding a last minute collision with buildings may have been the final nail; they had too few knots to give up to maintain a margin above stall?

Another interesting, but hopefully short-term mystery.

[Seeker]

All true Seeker, but I think your opinion is based on the above average skills you possess and not perhaps those of the masses (lol).

Thanks I guess but passing the ride and being qualified on the aircraft should be enough - shouldn't need an above average pilot.

[Don Hudson]

Canoehead;

I believe we'll see more effective and enlightening transparency from the Taiwanese than we've seen from the Indonesians.

There are some unverified comments about the "captain wanting the left engine looked at" prior to departure and the company refusing - also a comment from a passenger who had flown in this aircraft previously and had noted an anomalous vibration not experienced the other TransAsia ATRs he had flown in.

Both are unsubstantiated, but I consider them "part of the story" to eliminate or confirm.

(Original comment), I don't think there's a feathered prop on the left engine...(ed to add, the "hmmmm....", down below)

Hmmmm...

[vanishing point]

Blades looked feathered to me.

[Don Hudson]

Me too...two of them anyway; the blade at 12 o'clock isn't conclusive and the 3 o'clock position doesn't appear so...but the other two are in the feathered position. Obviously closer examination and the recorders will answer the question.

[Seeker]

Me too...two of them anyway; the blade at 12 o'clock isn't conclusive and the 3 o'clock position doesn't appear so...but the other two are in the feathered position. Obviously closer examination and the recorders will answer the question.

I'm not sure what you're saying - as far as I know it's virtually impossible for some to be feathered and others, on the same engine, to be unfeathered. The main point is that we cannot decide feathered or unfeathered based on the video. Shutter speeds, frame rates, conversions etc can make a turning prop appear stopped and vice versa so trying to do this is a waste of time. I know I also posted regarding this but upon reflection realize it's pointless.

[Don Hudson]

seeker- yes virtually impossible, so they were likely feathered!

I've given up all theories, on AirAsia and won't on this one...it is, as you say, "pointless"! ;-)

[Seeker]

Well, "pointless" to try to figure out if the prop was feathered from the video at least.

[boestar]

Dont forget that the blades have quite a twist to them so depending on the angle you are viewing from they may look unfeathered

[DEFCON]

The recorders have been read. The data will be released tomorrow, but perhaps not publically?

[JL]

...and don't forget that the initial//main impact forces can disrupt the pitch control mechanism in the prop hub to the point of allowing the blades to move in all directions during the remainder of the breakup sequence or during recovery. Detailed examination of the prop is required to determine blade pitch on impact - witness marks etc.

[blues deville]

Taiwan grounds fleet.

http://atwonline.com/safety/taiwan-orders-atr-72s-grounded-inspected-following-transasia-crash?NL=ATW-04&Issue=ATW-04_20150205_ATW-04_133&sfvc4enews=42&cl=article_2&YM_RID=CPEN1000000444072&YM_MID=1683

[airbrake]

TAIPEI, Taiwan -- One of the engines on TransAsia Airways Flight 235 went idle 37 seconds after takeoff, and the pilots may have shut off the remaining engine before attempting to restart them, but the plane crashed before that could happen, Taiwan's top aviation safety official said Friday.

The details were presented at a news conference in Taipei by Aviation Safety Council Executive Director Thomas Wang as preliminary findings from the flight data recorder.

Wednesday's crash into a river in Taipei minutes after takeoff killed at least 35 people and left eight missing. Fifteen people were rescued with injuries after the accident, which was captured in a dramatic dashboard camera video that showed the ATR 72 propjet banking steeply and scraping a highway overpass before it hurtled into the Keelung River.

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PHOTOS

Divers search for missing passengers

Search and rescue divers continue to search for missing persons at the site of a plane crash in Taipei, Taiwan on Feb. 6, 2015. TransAsia Airways Flight 235, with 58 people aboard, clipped a bridge shortly after takeoff and crashed into a river in the island's capital of Taipei on Wednesday morning. (AP / Wally Santana)

Wang said the plane's right engine triggered an alarm 37 seconds after takeoff. However, he said the data showed it had not shut down, or "flamed out" as the pilot told the control tower, but rather moved into idle mode, with no change in the oil pressure.

Then, 46 seconds later, the left engine was shut down, apparently by one of the pilots, so that neither engine was producing any power. A restart was attempted, but the plane crashed just 72 seconds later.

Wang said it was too early to draw firm conclusions about the reasons why the engines ceased producing power.

"It's only the third day so we can't say too much," Wang said. "We haven't ruled anything out."

Taiwanese Vice President Wu Den-yih, mindful of the island's reputation as a tourist destination and its tense relations with China where most of the flight's passengers were from, went to a Taipei funeral parlor for prayer sessions to pay respects.

At the parlour, where bodies are being stored, Wu expressed condolences and praised pilot Liao Chien-chung, who died in the crash. The pilots may have deliberately steered the plane away from buildings and into the river in the final moments.

"When it came to when it was clear his life would end, (the pilot) meticulously grasped the flight operating system and in the final moments he still wanted to control the plane to avoid harming residents in the housing communities," Wu said.

"To the plane's crew, the victims ... I here express condolences."

Divers continuing search for bodies

Divers with a local fire agency found one female and three male bodies Friday along the muddy Keelung River bottom about 50 metres from the crash site, a Taipei City Fire Department official surnamed Chen said.

The agency suspects the eight bodies that are still missing may be in equally murky areas and has sent 190 divers to look for them. Taiwan's Ministry of National Defense dispatched three S-70C rescue helicopters to search along a river system that runs into the ocean off Taiwan's northwest coast.

More than 30 relatives of victims cried wildly, prayed or were comforted by Buddhist volunteers at the riverside crash site as divers in black wetsuits brought back the four bodies. Some divers came ashore with their hands joined in prayer for the people they brought back.

The pilot's and co-pilot's bodies were found earlier with their hands still on the controls, Taiwan's ETToday online news service said.

Wang said the cockpit flight recorder was still being analyzed and a transcript would be provided as soon as possible.

Investigators are to issue a preliminary report on the crash within 30 days and a fuller report within 3-4 months. A final draft will be submitted within 8 months and the full investigation concluded in about a year, Wang said.

He said the engines had shown no problems before the flight and repeatedly stated that the plane would have been able to take off and fly even with only one engine working.

Earl Chapman of Canada's Transportation Safety Bureau told the news conference that the plane's Pratt & Whitney engines were known for their reliability.

"This engine type has millions of flight hours behind it with a very good safety record. So it's fairly unremarkable in that respect," said Chapman, who was participating in the investigation because the engines were made by Pratt & Whitney's Canadian division.

The same airline operated another ATR 72 propjet that crashed on an outlying Taiwanese-controlled island last July 23, killing 48.

Taiwan President Ma Ying-jeou's office said Thursday it was worried that air crashes would damage the island's reputation as a tourist destination.

Thirty-one of the passengers on Flight 235 were from China. Tourists from the mainland to Taiwan rose from a trickle before mid-2008 to a cumulative total of 9.7 million as of last year.

China has claimed sovereignty over Taiwan since a civil war in the 1940s, chilling relations until Ma took office in 2008 and opened dialogue that led to an agreement allowing tourist visits.

Tourists from China have also died in a construction site accident. A bus crash three years ago in eastern Taiwan injured 34.

The vice president's visit to the funeral home may be a "gesture to keep up benign relations," said Alexander Huang, strategic studies professor at Tamkang University in Taiwan.

As both sides handle the crash aftermath, a Chinese government minister in charge of Taiwan affairs postponed a visit scheduled for Saturday and Sunday.

The two sides also need more time to discuss four new domestic flight routes that China declared on its own last month, Taiwan's China policymaking body said in a statement. Taiwan opposes the new Taiwan Strait air routes, saying they could cause safety problems for its own domestic flights.

---

Bodeen reported from Beijing. Associated Press writer Ian Mader in Beijing and photographer Wally Santana and video journalists Johnson Lai and Tassanee Vejpongsa in Taipei contributed to this report.

Read more: http://www.ctvnews.ca/world/both-engines-failed-in-deadly-taiwan-plane-crash-1.2223440#ixzz3QxnNCalb

[Guest]

TransAsia ATR flight data suggests wrong engine shut down

By: ELLIS TAYLOR

SINGAPORE

Source:

in 3 hours

Flight-data recorder information suggests the crew operating the crashed TransAsia Airways ATR 72-600 may have shut down the left-hand engine of the aircraft shortly after the right-hand engine flamed out.

Taiwan’s Aviation Safety Council has released engine plots from the recovered flight-data recorder that appear to show that, shortly after takeoff, a master warning indicated a flame-out of the right-hand powerplant. The aircraft was at an altitude of around 1,200ft at the time.

The data indicates that the propeller of the right-hand engine feathered.

But less than a minute after the warning, the data shows a fuel shut-off to the left-hand engine. There is no indication on the data plot that a flame-out warning was active for this engine.

Around the same time, air traffic control communications show that the crew made a 'mayday' call, citing an engine flame-out.

Further data from ASC shows that around 42s after shutting off the fuel to the left engine, it was restarted, around the same time that a stall warning sounded.

At no time was fuel to the right-hand engine shut off, the data suggests.

The cockpit voice recorder stopped recording around 16s after the engine restart, indicating that the aircraft had crashed.

ASC is continuing its investigation, in collaboration with French and Canadian air safety investigators. Engine manufacturer Pratt & Whitney and ATR are also involved. The 2014-built ATR 72-600, registered B-22816, crashed shortly after takeoff from Taipei Songhan airport, while operating flight GE235 to Kinmen.

http://www.flightglobal.com/news/articles/transasia-atr-flight-data-suggests-wrong-engine-shut-408774/

[DEFCON]

It’s still early of course, but if reports are accurate, this one sure re-emphasizes trainings focus on the identification and confirmation of the correct engine before any handles are pulled.

I know it’s hindsight now, but the question has been asked of designers / regulators before. If it was considered important to have the relative handle illuminate during an engine fire event, why not the same when the thrust being delivered doesn’t match thrust /power lever position?

[Guest]

Latest Update

TransAsia GE235: Shutting down the wrong engine

By: DAVID LEARMOUNT

LONDON

Source: Flightglobal.com

in 6 hours

Taiwan's accident investigators have taken the unusual step of publishing part of the flight data recorder printout for the crashed ATR 72-600 almost as soon as it was available to them. There are no rules or protocols saying they must do so, and none saying they should not.

The printout they released concerns only the data for the engines. It is a series of graphical lines describing the state of 12 different engine parameters against a timeline, with barometric altitude also displayed. The graphs provide numerical values for some of those parameters; others just show whether a switch is on or off – like the fuel shut-off valve for example.

This data tells the investigators, in great detail, what happened, but still not – at this stage – why it happened.

The graph shows that the crew certainly suffered the engine "flame-out" they reported in a Mayday call to ATC: the turbine temperature for No 2 engine (the right-hand one) dropped, power was lost and the propeller auto-feathered.

But then, in the stressful situation prevailing from that point, the crew carried out the shutdown drill for the working engine, so it stopped too.

Why would the investigator release this information so soon without knowing the cause?

The investigators knew the information about this critical mistake would soon have to be released, and it looks as if they believed it would be better to publish the cold data that shows what occurred, rather than to make a statement – without releasing the data – that could be interpreted as a premature judgement about the human factors of this case.

Perhaps the most famous previous case in which a disaster occurred because an engine failed and then the crew mistakenly shut down the good engine (rather than the damaged one) was the BritishMidland Boeing 737-400 crash at Kegworth, UK, in 1989. In that case 47 of the 126 people on board died.

In the TransAsia case the total airborne time for flight GE235 was 2min 40s.

All was going well for 45s after take-off, but as the aircraft was climbing through about 1,200ft (pressure altitude) the turbine temperature for the No 2 engine dropped and the engine auto-feathered. It is not clear why. The aircraft continued to climb on the power from the remaining engine, reaching a maximum height of about 1,650ft.

But during that short period the crew allowed the power lever (throttle) of the failed No 2 engine to stay where it was, and started slowly pulling back the power lever of engine No 1 (the working left engine). When it had been reduced almost to idle setting, the fuel was shut off and the right engine also feathered. Just before they shut off fuel to No 1, they advanced the throttle of the failed No 2 engine as far as they could, as if it would provide them with additional power.

At that point there would have been a total absence of engine and propeller noise, but lots of alarms going off as systems lost their electrical power. From that time onward the crew had, as it turns out, 1min 15s of gliding time before hitting the surface. That is not really long enough to go through a successful engine re-start drill, but they did begin an attempt to re-light No 1 about 15s before impact.

http://www.flightglobal.com/news/articles/transasia-ge235-shutting-down-the-wrong-engine-408790/

[Seeker]

Very discouraging.

[rudder]

And a perfectly serviceable B777 is flown into a break wall just short of the runway in SFO.

There is a theme here and refusing to acknowledge it is at best irresponsible and at worst criminal.

The money paid for qualified, experienced, and competent flight crews is worth every penny and often taken for granted. These are examples of what happens in less supervised and less regulated environments where competency in basic flying maouevers is apparently not a sure thing.

Hope that the North American operators are watching and being thankful for the experienced and proficient pool of commercial pilot talent that they employ.

[Guest]

"When it had been reduced almost to idle setting, the fuel was shut off and the right engine also feathered."

I think they mean, the 'left engine also feathered'.

A very expensive day on more than one level. And totally preventable.

[Don Hudson]

Flight data:

[Boney]

Oh my lord.

[Guest]

What is astounding to me, is not only the apparent mis-identification of the failed engine, but the time interval between the power loss on #2 and the PLA decrease on #1: mere seconds.

What kind of crew coordination and procedure is that? Unbelievable if what I'm perceiving from that data actually happened. But will know for certain when the final report comes out.