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General Forums => The O' Club => Topic started by: SysError on February 04, 2015, 09:33:08 AM

Title: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 04, 2015, 09:33:08 AM
http://www.bbc.com/news/world-asia-31125735

12 died
58 souls

 :(
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 04, 2015, 10:01:04 AM
This is turning into a mess.

Death count up.

New footage.

'Bridge planned' in TransAsia Airways plane rescue effort:

http://www.bbc.com/news/world-asia-31125184

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 04, 2015, 10:05:14 AM
Rescue footage:

toddler rescued from river:

http://www.bbc.com/news/world-asia-31132227


Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 04, 2015, 10:32:37 AM
That's what, the fourth or fifth ATR72 TransAsia has crashed?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PanosGR on February 04, 2015, 10:44:34 AM
(http://)(http://i186.photobucket.com/albums/x39/PanosGR/PLANE_zps8b617f3f.jpg) (http://s186.photobucket.com/user/PanosGR/media/PLANE_zps8b617f3f.jpg.html)

https://www.youtube.com/watch?v=sPdwCnwuZ8w




Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Nath[BDP] on February 04, 2015, 10:51:48 AM
what the diddly!!!!!!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 04, 2015, 10:58:35 AM
That's what, the fourth or fifth ATR72 TransAsia has crashed?

I do not know the number for that, but here is a BBC piece on Is flying getting more dangerous?  Kind of interesting.

http://www.bbc.com/news/world-asia-31132573

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 04, 2015, 11:10:21 AM
More people are flying more often.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 04, 2015, 11:17:49 AM
Wiki lists 15 accidents with the ATR 72. Of those four were TransAsia flights. All with fatalities.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Slate on February 04, 2015, 11:43:02 AM
    Couldn't really tell but looked like left engine was not rotating like right one.  :pray
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Mister Fork on February 04, 2015, 03:02:50 PM
   Couldn't really tell but looked like left engine was not rotating like right one.  :pray
Keen eye Slate - buddy of mine at work who is a former Air Force mechanic noticed the same thing when we watched it at my desk this morning and that he stalled it right out in an attempt to get it to the river rather than into the apartment buildings.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: FiLtH on February 04, 2015, 03:41:07 PM
 What a job missing all that concrete and hitting the river.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: MrRiplEy[H] on February 04, 2015, 03:46:42 PM
Suspiciously many stall related crashes with the ATR.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 04, 2015, 04:01:19 PM
Acording to liveatc the pilot said "mayday, engine flameout" on the radio and as noted it looks like the left engine are out. Most likely they tried to reach the river but stalled above the bridge. But an engine failure should not bring the plane down like this. Either the pilots made some errors and failed to fly the plane on one engine or they might have lost power on both engines.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 04, 2015, 04:30:52 PM
Bad fuel perhaps.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: icepac on February 04, 2015, 06:09:43 PM
I think he sacrificed his airspeed to clear the buildings in hoping he could get enough airspeed by descending near the river.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Busher on February 05, 2015, 08:42:40 AM
Have a few hours on this airplane and the Dash-8 (very similar).

If you fail to stop the yaw with rudder and promptly feather the prop on the failed engine, this will result
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 05, 2015, 09:31:28 AM
Have a few hours on this airplane and the Dash-8 (very similar).

If you fail to stop the yaw with rudder and promptly feather the prop on the failed engine, this will result

If he had would he have cleared the apartments?  How much time do you have and what do you lose in speed and alt?

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Busher on February 05, 2015, 10:39:34 AM
All licensed airports have published obstacle clearance procedures based upon natural or man-made terrain. Assuming the airline's safe dispatch procedures include this performance analysis (required climb gradient), the airplane will, if properly flown will clear all obstacles in its departure path after suffering an engine failure on takeoff.

Failure to control the yaw with rudder, failure to fly the aircraft at the correct single engine climb speed, and failure to feather a windmilling propeller after engine failure all work to degrade climb performance. Any one of these can cause a complete loss of control. I am not suggesting that this was the cause of the accident - we'll have to wait for the official report.

I only have about 150 hours on the ATR but more than 5000 on the Dash-8. They are very similar and used exactly the same P&W turbo-prop engine.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 05, 2015, 02:19:52 PM
Have a few hours on this airplane and the Dash-8 (very similar).

If you fail to stop the yaw with rudder and promptly feather the prop on the failed engine, this will result
:airplane: My big compliant about the design of this aircraft is the size of the elevator and rudder. I think the engineers sacrificed handling at low speeds for high speed cruise numbers. If this aircraft had, say, just 20% larger rudder and elevator, the VMC would be a lot lower and I think serveral of these accidents could have been prevented. Again though, money gets in the way of safety 
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 05, 2015, 02:22:29 PM
Suspiciously many stall related crashes with the ATR.
:airplane: You are correct! Since 1988, someone should have said, bad design, lets redo the tail surfaces and give the pilots a better chance in low speed realm's.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 05, 2015, 02:24:09 PM
What a job missing all that concrete and hitting the river.
:airplane: By the time you can see the aircraft in the video, the pilot had no control over what the aircraft was doing!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 05, 2015, 04:29:41 PM
I would not use the word "many" in relation to the number of fatal accidents involving the ATR 42/72. 11 fatal accidents in 30 years from 1200 produced aircraft doesn't strike me as excessive. However that four fatal accidents (including two where only the crew perished) were TransAsia flights does.

http://www.airsafe.com/events/models/atr.htm
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 05, 2015, 06:33:18 PM
I would not use the word "many" in relation to the number of fatal accidents involving the ATR 42/72. 11 fatal accidents in 30 years from 1200 produced aircraft doesn't strike me as excessive. However that four fatal accidents (including two where only the crew perished) were TransAsia flights does.

http://www.airsafe.com/events/models/atr.htm
:airplane: I am reminded of something "Chuck Yeager" once said: "if it don't look right, generally speaking it doesn't fly right"! I think the tail surfaces are out of sync with the rest of the airframe, especially the stretch 600 model.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 05, 2015, 06:50:18 PM
How many planes did Chuck Yeager design? And how would the tail surfaces cause the left wing to stall as evident in the crash footage?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 05, 2015, 06:55:30 PM
Lack of rudder authority would cause an uncontrolled yaw.  Once the plane starts yawing, drag increases tremendously, and it quickly falls below single engine speed.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Puma44 on February 05, 2015, 07:02:41 PM
Engine failure/rollback after V1 without immediately applying corrective rudder (dead foot,dead engine) most often results in an uncontrollable roll and bad results.

To serve as a commercial airliner in the U.S, the ATR had to demonstrate, during certification, the ability to experience an engine failure after V1, climb on one, remain controllable, and land safely.

It could be whichever pilot was flying this aircraft, was caught off guard, and reacted to late to counter the yaw and ensuing roll over.  A very dynamic and fast pace of events right after takeoff. 
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Busher on February 05, 2015, 07:11:05 PM
:airplane: My big compliant about the design of this aircraft is the size of the elevator and rudder. I think the engineers sacrificed handling at low speeds for high speed cruise numbers. If this aircraft had, say, just 20% larger rudder and elevator, the VMC would be a lot lower and I think serveral of these accidents could have been prevented. Again though, money gets in the way of safety 

I don't totally disagree...both this airplane and the Dash-9 are Butt-ugly and under-powered. The cost of short haul economy I suppose.

That being said, they both have more than adequate rudder authority to fly and climb at V2 holding the airplane straight against a windmilling prop. Once the failed engine's prop is feathered, they don't require full rudder application to continue the climb at best single engine speed.

It appears to me from the video that the accident aircraft's failed engine's prop was not feathered.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 05, 2015, 07:14:42 PM
Neither the vertical stabilizer or the rudder seem undersized to me compared to similar aircraft. Also the argument that a "stretched" version would need larger tail surfaces is contrary to elementary physics. The longer the moment arm the smaller the force needed to move it. The longer the fuselage the more authority the control surfaces have.

(https://dl.dropboxusercontent.com/u/26232318/AH/ATR%2072-600%20series%20in%20flight%205.jpg)

(https://dl.dropboxusercontent.com/u/26232318/AH/Flybe_dash8_g-jecl_takeoff_manchester_arp.jpg)

(https://dl.dropboxusercontent.com/u/26232318/AH/bae-atp-turboprop_2.jpg)

(https://dl.dropboxusercontent.com/u/26232318/AH/beech1900d_1.jpg)
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 05, 2015, 07:25:31 PM
Actually I think the Dash-8 is quite beautiful with those long nacelles and the drooping nose.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Delirium on February 05, 2015, 07:33:34 PM
It could be whichever pilot was flying this aircraft, was caught off guard, and reacted to late to counter the yaw and ensuing roll over.  A very dynamic and fast pace of events right after takeoff. 

That was my first impression too, saw the roll and only then did I notice the engine out.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 06, 2015, 07:23:21 AM
So it looks as if both engines lost power.

http://www.bbc.com/news/world-asia-31162351

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: ebfd11 on February 06, 2015, 07:35:14 AM
Imagine being the guy in the taxi it hit...
http://www.bbc.com/news/world-asia-31143710

I would have needed a new pair of shorts.

LawnDart
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 06, 2015, 07:45:43 AM
From SysError's link:

Quote
"Then the other
engine was shut down manually. The pilot tried to restart the engines but to no avail.

"That means that during the flight's final moments, neither engine had any thrust. We heard 'Mayday' at 10:54:35," he added.

The flight, which had been bound for Taiwan's Kinmen Island, crashed into the Keelung River just 72 seconds later.

The plane, an ATR 72-600, is able to fly with just one functioning engine. Mr Wang said it was not clear why the left engine had been shut down.
The engine we see running is actually the malfunctioning engine. The crew shut down the left engine manually. Regardless of how much earl1937 would like it differently it seems like a pilot error rather than toejamty design.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Rich46yo on February 06, 2015, 10:13:45 AM
Quote
To serve as a commercial airliner in the U.S, the ATR had to demonstrate, during certification, the ability to experience an engine failure after V1, climb on one, remain controllable, and land safely.

And the two engine argument goes on. As far as I know, and correct me if the 747 production hasnt been stopped, the A380 is the only 4 engined regional/long range commercial aircraft still being produced. I know the A340 production has ceased and all regional jets are now two engined. I remember the row when they were trying to get the 777 certified for long haul on its two engines.

The simple fact is two engined people haulers make more money. It all comes down to profit made per passenger in seat. I dont think "speed" has much to do with hauler design when compared to MPG of fuel. Every component of a hauler is made for get Jack and Jill from A to B as cheaply as possible. Of course NOT falling out the sky is also considered.

These Asian start ups are really upping the ante on aircraft turn around/usage and employee productivity. The market is huge and growing every day and while I have no hard facts on TransAsia I know Air Asia is setting new records for keeping its airplanes in the air, and for discount rates. Spirit airlines does the same here and I can attest their airplanes are always having trouble. Man I'd never fly Spirit, tho at least we probably have higher safety standards then an Asian airline does. At least the regionals. I think I'd pass on TransAsia for a puddle jump. Losing two of your 10 ATR's doesnt look good.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 06, 2015, 12:14:06 PM
From SysError's link:

The engine we see running is actually the malfunctioning engine. The crew shut down the left engine manually. Regardless of how much earl1937 would like it differently it seems like a pilot error rather than toejamty design.
:airplane: There is a good "black box" report in aircraft and vehicles, which says the left engine, or #1 was the inop engine during the emergencie and now it looks like they may have shut down the good engine, while trying to clean up #1. If that was the case, yes it would be pilot error!
My whole contention about this aircraft is that when operating at slow speeds, it is operating right on the edge because of the small rudder and elevator, more the rudder size than the elevator.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 06, 2015, 12:22:06 PM
You keep saying it has a small rudder, but it clearly doesn't compared to similar aircraft.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Serenity on February 06, 2015, 05:03:39 PM
You keep saying it has a small rudder, but it clearly doesn't compared to similar aircraft.

Size of aircraft does not necessarily equate to similar aerodynamic behavior.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Flifast on February 06, 2015, 05:28:40 PM
The right engine went into auto feather at about 1500 ago but the crew reduced power on the left engine and then shut down the left engine.  I've done a few 100 shutdown and restarts and if they figured out the error and tried to restart and unfeather the left engine it would make the aircraft roll hard left.  When the left engine comes out of feather it's like going from 4th gear to first gear and the drag on that prop is huge.  We've done it a few times with both engines feathered at 10,000 feet and expect to lose 2000 before its out of feather and providing forward thrust.

I have a copy of the FDR with just a few channels so you can't tell control inputs, just engine data.

Fli
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 06, 2015, 05:38:31 PM
You keep saying it has a small rudder, but it clearly doesn't compared to similar aircraft.
:airplane: The "moment arm leverage" on the vertical axis is something that is computed when designing the aircraft. My question is: should it be 150% of normal "throw" or is it one those figures right on the "button".
My question is this: is the rudder size and throw the same as on the short version, I think the 100, if so, you going to tell me that with the fuselage extend another 12 feet, that you  should not add some rudder dimension's to make up for the length of the fuse?
When building the rudder or any other part on the aircraft, it is formed in "jig" and the dimension's stay the same, but suppose they change the length of the fuselage, now they must build a whole new "jig", parts have to cut larger and etc, don't you think that cost's a lot money? Yep
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 06, 2015, 05:42:00 PM
The right engine went into auto feather at about 1500 ago but the crew reduced power on the left engine and then shut down the left engine.  I've done a few 100 shutdown and restarts and if they figured out the error and tried to restart and unfeather the left engine it would make the aircraft roll hard left.  When the left engine comes out of feather it's like going from 4th gear to first gear and the drag on that prop is huge.  We've done it a few times with both engines feathered at 10,000 feet and expect to lose 2000 before its out of feather and providing forward thrust.

I have a copy of the FDR with just a few channels so you can't tell control inputs, just engine data.

Fli
:airplane: Well, it is an interesting discussion! a lot of good posts and replies, a lot of good technical stuff to!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: USRanger on February 06, 2015, 05:52:20 PM
The pilot really deserves kudos and much respect for going for the river instead of hitting what is probably a butt-ton of buildings all around there.  Sad to think that by the time the pics/footage is taken, everyone on-board knows they are dead. :(
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 06, 2015, 06:00:23 PM
In most cases the shorter versions of a plane need a bigger fin, A318 for example have a bigger fin than the bigger brothers. Short plane means less stability and thus need a larger fin. I cannot see that the ATR-72 has a undersized fin or rudder. Max demonstrated cross wind on dry runway its 35 kt for the ATR 72-600 and that indicate that it has a very good rudder.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: BaDkaRmA158Th on February 06, 2015, 07:43:19 PM
Very sad.


 :pray for the lost ones.  :angel: to those who survived.  :salute for the pilots.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: SysError on February 06, 2015, 08:01:41 PM
Very sad.


 :pray for the lost ones.  :angel: to those who survived.  :salute for the pilots.

Well Said.

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: rpm on February 07, 2015, 03:59:58 AM
Obviously a sound card issue.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 07, 2015, 09:08:03 AM
In most cases the shorter versions of a plane need a bigger fin, A318 for example have a bigger fin than the bigger brothers. Short plane means less stability and thus need a larger fin. I cannot see that the ATR-72 has a undersized fin or rudder. Max demonstrated cross wind on dry runway its 35 kt for the ATR 72-600 and that indicate that it has a very good rudder.
:airplane: The only reason for the rudder is to "overcome the adverse yaw, created by the down turned aileron when making a turn". That is the basic reason for a rudder, reason, simply put, if you start a left turn, the nose of the aircraft, without the use of rudder, will turn right first and only then will it come back to left as you want! If climbing, which these guys were doing at the time, non use of the rudder would increase the drag on the aircraft because it is now slipping in the turn, which also raises the stalling speed to a higher than normal value, which could have caused the left turn which this aircraft did prior to losing control alto gather.  Now there are other functions for the rudder in addition to that, one being, overcoming the adverse yaw created by a failed engine and the torque and "P" factor now created by the still operating good engine! Last, but not least, controlling yaw about the vertical axis of the aircraft in all flight realms.
When teaching basic flight instructions to students, one good lesson for them is to teach them to "push the high rudder pedal to correct the low wing condition, if one, example, in a stall, if the aircraft drops off into a low left wing down conf, then use the right rudder to correct the low wing condition, of course using aileron to assist you in getting back to wings level attitude. Why is that important, because the stalling speed of the aircraft is higher in a turn than in level flight, so no matter what is happening, you want to maintain a wings level attitude until you regain flying speed. And to, if you don't get the nose down or power restored, you are just going to stall again. Also, when stalling an aircraft, your nose is going to be pointing down, but in a wings level attitude, you will regain flying speed much quicker than in a turn!.
Again I make the argument that if the ATR 72 had a larger rudder, then it could operate at most slower speeds than it does now!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 09:32:22 AM
Earl, at what speed does the ATR's rudder become ineffective in a one engine configuration?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 07, 2015, 10:38:48 AM
PR3D4TOR, how much multi-engine time do you have?  
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 10:43:22 AM
I'm not a pilot if that's what your asking.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Shamus on February 07, 2015, 10:51:07 AM
Earl, at what speed does the ATR's rudder become ineffective in a one engine configuration?

Thats like asking how long is a piece of string.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 07, 2015, 10:54:33 AM
This is a research paper showing that the ATR 72 should have its vertical stabilizer increased by 12.5%.

http://www.fzt.haw-hamburg.de/pers/Scholz/paper/RRDPAE-2008-Presentation_ATR72.pdf
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:13:07 AM
Thats like asking how long is a piece of string.

No. It's like asking at what speed does the ATR stall in a given configuration. Obviously Earl knows the minimum allowable speed for the ATR in a one-engine configuration, and that it is above stall speed, or he wouldn't claim that the ATR could operate at a lower speed with a larger rudder. Right?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:18:58 AM
That "research paper" by some student is full of assumptions and hardly relevant.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Shamus on February 07, 2015, 11:20:47 AM
No. It's like asking at what speed does the ATR stall in a given configuration. Obviously Earl knows the minimum allowable speed for the ATR in a one-engine configuration, and that it is above stall speed, or he wouldn't claim that the ATR could operate at a lower speed with a larger rudder. Right?

You have a lot of variables to plug in there to get an answer, "one engine" is only one of them.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 07, 2015, 11:21:57 AM
That "research paper" by some student is full of assumptions and hardly relevant.

It's a Master's Thesis.  Hardly 'some student'.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:27:05 AM
It's still full of assumptions. Most critically about the mass of various components.

The people who actually designed the aircraft have all had their masters for some time...
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:28:26 AM
You have a lot of variables to plug in there to get an answer, "one engine" is only one of them.

The lowest allowable speed in different configurations should be printed in the flight manual and checklists.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Shamus on February 07, 2015, 11:36:48 AM
The lowest allowable speed in different configurations should be printed in the flight manual and checklists.

Hehe ok, whatever you say :D. What environmental conditions do you plan to plug into this little equation?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:38:38 AM
From another bbs:

"VMC, specifically in this context, VMCa, is the minimum airspeed at which controlled flight can be achieved with an engine out, i.e asymmetric thrust. (VMC = minimum controllability speed). Drop below VMCa and, put very simply, the airflow over the rudder is not enough for it to retain authority to counteract the thrust asymmetry. You then end up in an uncontrollable yaw which leads to an uncontrollable roll and spiral dive.

VMCg is is min control speed on the ground, so the speed at which the rudder has enough authority to stop you spinning off the runway if you have asymmetric thrust."


So what's the VMCa of the ATR 72, and is it unreasonably high compared to other, similar types?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 07, 2015, 11:42:06 AM
My apologies.  Here is the full Master's Thesis.  Please reference page 120 for vertical stabilizer sizing and corresponding supporting mathematical calculations.  http://www.fzt.haw-hamburg.de/pers/Scholz/arbeiten/TextNita.pdf  
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:45:16 AM
Ok, on another bbs they came up with the following:

Vmca Flap 15 1000 ft 25°c  93 kts

Vstall Flap 15 a 22000 kg 100 kts

Vstall Flap 15 a 18000 kg 91 kts


So when heavy (take-off) the ATR's stall speed is faster than its control speed in a one-engine configuration. The plane would stall before the rudder becomes ineffective.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 11:55:55 AM
Here's the Quick Reference Handbook for the ATR 72-500.

It has the flame-out emergency procedure and how to determine Vmca.



http://www.scribd.com/doc/141616443/ATR-72-500-QRH#scribd
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Toad on February 07, 2015, 12:36:03 PM
Quote
Data from the "black box" flight recorders retrieved from the wreckage suggests the pilots shut down one engine after the other lost power.  http://www.bbc.com/news/world-asia-31162351

This will likely become the textbook example of How NOT To Perform the V1 Cut Maneuver in Recurrent and Initial Ground Schools around the world. It will also be featured in the CRM classes with emphasis on crew co-ordination in shutting down the correct engine.

Quote
Earlier, TransAsia said all of its pilots would be retaking proficiency examinations following the disaster.

http://www.bbc.com/news/world-asia-31162351

A really good idea; I am actually surprised to see an airline management team directly and immediately address a serious training issue in their company. Bravo for TransAsia.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Rich46yo on February 07, 2015, 01:39:01 PM
I'd like to know how many hours those pilots had been clocking in the weeks prior to that crash.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 07, 2015, 02:49:22 PM
I'd like to know how many hours those pilots had been clocking in the weeks prior to that crash.
:airplane: can't answer that question, but will say this: It comes down to basic stick and rudder control of the aircraft, where are not you are descending or in level flight! All pilots, who are trained correctly in cockpit interaction in an emergency should both agree on which engine is to shut down. I would always ask the Captain or co=pilot, depending on which position I was flying in to respond back to me verbally which engine had failed, by reference to dead foot, dead engine, manifold pressure or in this case compresser speed, or even some have old EPR gauges or some did anyway. On top of that, that is a master watning light for each engine with a big number right in the middle of the thing.
My question, if they were a 1,000 high, why were they in such a hurry to shut down the dead engine anyway? This has been an amazing collection of thoughts, suggestions and yes some critics of what happen!
Almost in every ATR72 accident, there has been a loss of control! Wonder how many of those could have saved with a 12% larger rudder and vertical stab? 
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 07, 2015, 02:54:49 PM
Earl, at what speed does the ATR's rudder become ineffective in a one engine configuration?
:airplane: It would depend on the estimated weight at takeoff, by the flight ops dispatcher, forget what they were called, and the agreement by the Captain, at which he would sign a document stating that he agrees with dispatch about the weight.
That are charts with various flap settings to determine the VMC at a certain weight!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Toad on February 07, 2015, 02:57:14 PM
Rudder Schmudder.

They were dead as soon as they shut down the only remaining engine putting out power.

Can't blame it on design.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 07, 2015, 03:07:44 PM
I'm not a pilot if that's what your asking.
:airplane: Sir, with all due respect, if you are not a pilot and are just going by the "book", here is something you won't find in a book that if you don't do, you will DIE! Fly the aircraft first, navigate second and communicate third, what did he, the capt do, started hollering "mayday" when he should have been thinking about flying the aircraft.
I appreciate your comments, however uninformed they are, we are just having a general, "wonder what happened" discussion and none of us will know until the "boxes" are analyzed.

I was giving a check ride to a ATR applicant one time in a DC-3 and picture this: we were at altitude of 8,000 feet, we were simulating an approach to an airport at 7,000 feet, he has the airspeed nailed down good, heading was excellent, vertical speed right where it was supposed to be, and then I casually shut the fuel down to left engine. As soon as it, the left engine quit due to lack of fuel, we are now down to about 600 feet above the simulated ground and what does he do, starts looking for the paper which has the VMC at our current weight, in case he has to go around!
Needless to say, I failed the applicant, he should have known those figures by heart, and he didn't!!!
And by the way, he was down to 5500 feet before he got everything cleaned up, feathered engine and other items on check list. Since the ground was supposed to be a 7,000 feet, don't you guess he and everyone in back would more than likely be dead?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 07, 2015, 03:15:47 PM

Almost in every ATR72 accident, there has been a loss of control! Wonder how many of those could have saved with a 12% larger rudder and vertical stab?  

I would say none. If you just look at the accidents most are Wheather related and/or human errors. Can u show us any hard fact that there is a design flaw in the rudder of the ATR? And seriously, don't u think that such a thing would have been unnoticed by air crash investigators?
(And doesnt all air crashes involves loss of control....)
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 07, 2015, 03:17:59 PM
:airplane: Sir, with all due respect, if you are not a pilot and are just going by the "book", here is something you won't find in a book that if you don't do, you will DIE! Fly the aircraft first, navigate second and communicate third, what did he, the capt do, started hollering "mayday" when he should have been thinking about flying the aircraft.
I appreciate your comments, however uninformed they are, we are just having a general, "wonder what happened" discussion and none of us will know until the "boxes" are analyzed.

I was giving a check ride to a ATR applicant one time in a DC-3 and picture this: we were at altitude of 8,000 feet, we were simulating an approach to an airport at 7,000 feet, he has the airspeed nailed down good, heading was excellent, vertical speed right where it was supposed to be, and then I casually shut the fuel down to left engine. As soon as it, the left engine quit due to lack of fuel, we are now down to about 600 feet above the simulated ground and what does he do, starts looking for the paper which has the VMC at our current weight, in case he has to go around!
Needless to say, I failed the applicant, he should have known those figures by heart, and he didn't!!!
And by the way, he was down to 5500 feet before he got everything cleaned up, feathered engine and other items on check list. Since the ground was supposed to be a 7,000 feet, don't you guess he and everyone in back would more than likely be dead?

And because of that the ATR is dangerous?
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 07, 2015, 03:28:56 PM
Earl, I already posted the QRH on the ATR showing all the info I need to know. At take-off weight the ATR's Vmca is below stall speed. You could increase the size of the rudder tenfold and it wouldn't make a difference. You're a pilot (used to be at least), and that's fine. However, aircraft are designed by engineers not pilots. There's nothing wrong with the ATR. Its rudder authority is adequate. It is not a "death trap" as you so not eloquently called it. The designers of the ATR are not idiots as you called them. If any idiot was involved he was a pilot. With all due respect.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Busher on February 07, 2015, 07:56:57 PM
Gentlemen;

There is nothing wrong with the design of the ATR. It's probably been most widely flown in the USA and Canada with an admirable safety record. A tremendous number of American and Canadian regional airlines flew them along with the Dash-8 in ridiculously huge numbers.

I can say from personal experience (despite the comments of our apparent FAA examiner) that it is a very easy airplane to fly in normal and abnormal flight configurations (eg. single engine, flapless, etc.).  Simply put it does everything fairly well and places few demands on the pilots.

Why don't we just wait and see what the official report has to say.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 09, 2015, 04:57:22 AM
(And doesnt all air crashes involves loss of control....)

Not always. Many are "controlled flight into terrain", usually at night or in bad weather. Flying into mountains and such.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: manurin on February 09, 2015, 05:53:29 AM
Has anyone noticed?, the left horizontal stab looks to be damaged prior impacting the taxi / bridge, which could mean that the plane could have clipped it on top of one of the building after-all ?

Maybe if this was the case, this could have also contributed to the plane stalling to the left?

here are 2 pics where on both of which you can see the clipped vertical stab.

https://www.dropbox.com/s/nt4ikw2zljsnsmh/pic%201.jpg?dl=0
https://www.dropbox.com/s/dfsuuxweem5jco7/pic%202.jpg?dl=0
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 09, 2015, 06:03:46 AM
Yes, the left horizontal stabilizer seems damaged.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 09, 2015, 06:41:59 AM
no it could not have hit a buliding with horizontal stab. Not without having some other part hitting the building too.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 09, 2015, 07:12:15 AM
It could have hit cables or wires in between buildings.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: MrRiplEy[H] on February 09, 2015, 07:31:24 AM
It could have hit cables or wires in between buildings.

Or the reason for the engine going feathered was a large component flying off it and hitting the stab.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: NatCigg on February 10, 2015, 09:07:52 PM
no it could not have hit a buliding with horizontal stab. Not without having some other part hitting the building too.

It could be a optical illusion but the plane banks left at the moment the tail is over a building. if so the debris should be found.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Zimme83 on February 11, 2015, 01:28:17 AM
It could be a optical illusion but the plane banks left at the moment the tail is over a building. if so the debris should be found.

Its more likley that the pilot is pulling up and that the position of the elevator is fooling the eye.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Wolfala on February 11, 2015, 10:56:54 AM
   
John Ylinen:
Clearly this airlines training and those two pilots were not at the required level.
   

TAIPEI, Taiwan (AP) - Taiwan's aviation authority has ordered the suspension of 10 pilots from TransAsia Airways who failed a proficiency test given after one of the airline's planes crashed, killing at least 42 people.

The Civil Aviation Administration said Wednesday the 10 failed the oral exam on handling emergency situations administered after the Feb. 4 crash and need to be retrained. It said 19 other pilots who did not take the test would also be suspended.

The turboprop ATR 72-600 crashed minutes after takeoff from Taipei's airport. Fifteen of the 58 people aboard were rescued and one person is still missing.

A preliminary investigation indicated the plane's pilots shut off a running engine after its other engine went idle, a move that aviation experts said was an error.

More fully:

(Reuters) - The Taiwan government ordered all airlines review their safety protocols on Wednesday after nearly half of the pilots trained to fly TransAsia's ATR twin-engined aircraft were suspended following last week's fatal crash in the capital.

Taiwan's aviation regulator said 10 of TransAsia's 49 ATR pilots had failed oral proficiency tests on handling the aircraft during engine failure. A further 19 pilots did not take the test, due to sickness or because they were not in Taiwan, the Civil Aviation Authority (CAA) said.

The 29 pilots who failed or did not take the test have been suspended, the CAA said.

"The result is not acceptable for us," TransAsia chief executive Peter Chen told a news conference. "We will definitely strengthen their training."

Authorities ordered the tests after one of the airline's ATR 72-600s crashed into a river in Taipei killing at least 42 of the 58 on board.

TransAsia Flight GE235 lurched between buildings, clipped an overpass with one of its wings and crashed upside down into shallow water shortly after taking off from a downtown Taipei airport last Wednesday.

Initial data indicates that the plane lost power in one engine after take-off from Taipei's Songshan airport. The power was then cut in the other engine.

Officials in Taiwan and industry analysts have said evidence presented so far raises questions over whether the pilots may have accidentally cut the wrong engine.

"The lunar Chinese new year holiday is coming... We'll ask every local airline to check their flight safety," Chen Jian-Yu, the transportation and communications minister, told reporters after the TransAsia test results were made public.

This was the second TransAsia ATR crash in seven months, and the fifth crash involving the airline since 1995, raising questions about safety standards at Taiwan's third largest carrier.

The pilot and co-pilot of the almost-new turboprop ATR 72-600 were among those killed.

FAIL AGAIN, YOU'RE OUT

A TransAsia pilot said the tests were conducted by a CAA official and a pilot from rival carrier Uni Air, a subsidiary of EVA Airways Corp.

"Some of us have stayed up all night to prepare for the tests. The result will affect our career developments significantly," said the pilot, declining to be identified due to the sensitivity of the issue.

"Those who failed will be suspended for one month. They will be given another month for preparation. If they fail again, they will be fired," the pilot told Reuters.

TransAsia has canceled at least 142 flights since the crash.

Initial data from the flight recorders indicate the plane lost power in one of its engine just after lifting off, Taiwan's Aviation Safety Council (ASC) said on Friday.

The crew then shut down the other engine, which was working, and attempted to restart it shortly before the aircraft crashed.

Commercial aircraft can fly with just one working engine, and the authorities have not released any information from the recorders that indicates why the pilots shut down the working engine.

They said on Friday, however, that a combined loss of thrust caused the almost new aircraft to stall soon after take-off.

The plane was powered by two Pratt & Whitney PW127M engines. Pratt & Whitney is part of United Technologies.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Rich46yo on February 11, 2015, 12:03:25 PM
The kid piloting that thing was 28yo and had 8,000 hours. His co-Pilot was 30yo and had 5,000 hours.

Thats a lot of hours to "not know" which engine to turn off.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Wolfala on February 11, 2015, 12:08:08 PM
The kid piloting that thing was 28yo and had 8,000 hours. His co-Pilot was 30yo and had 5,000 hours.

Thats a lot of hours to "not know" which engine to turn off.

That's a lot of Parker Pen time.

Then again I stopped counting at 7000 hours at around 28 years, but then again I started flying in 92 and bought my first plane at 25.

Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: Toad on February 11, 2015, 12:44:50 PM
Failed the ORAL? Wow. That says something.

I note they say nothing about an actual proficiency check in a simulator.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: earl1937 on February 11, 2015, 03:10:43 PM
Failed the ORAL? Wow. That says something.

I note they say nothing about an actual proficiency check in a simulator.
:airplane: You make a good point Toad! I doubt if this airline has a simulator because they are so costly. Most airlines are not run by pilots, but accountants and a lot decisions are made based on the "number"!
A good example of that is the old Eastern air lines! When "Eddie Rickenbacker" was running the airline, it was booming growing airline! The minute a accountant took over the reins of day to day operations, it started going downhill, and the rest is history!
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: PR3D4TOR on February 11, 2015, 04:37:45 PM
Shutting down the wrong engine is unfortunately not just a rookie mistake. It has happened several times before, even with a highly experienced crew in England crashing a B737.
Title: Re: Footage of TransAsia Airway plane crash in Taipei
Post by: DaveBB on February 11, 2015, 05:07:32 PM
C-5a crew in Dover shut down the wrong engine and crashed landed.