Utair ATR 72 Crash in Siberia
Join Date: May 2004
Location: 3.5 from TD
Age: 47
Posts: 1,042
Likes: 0
Received 0 Likes
on
0 Posts
according to USA Fox News, smoke was observed trailing from an engine
Join Date: Aug 2009
Location: Germany
Age: 67
Posts: 1,777
Likes: 0
Received 0 Likes
on
0 Posts
Join Date: Mar 2011
Location: 0ft AGL
Age: 33
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
The Interstate Aviation Committee (IAC) came up with first information from earlier retrieved data recorders:
1. Engines were working until the ground impact.
2. After T/O aircraft reached height of 210m, then banked right 35, then left 50 before hitting the ground.
May all perished rest in peace.
1. Engines were working until the ground impact.
2. After T/O aircraft reached height of 210m, then banked right 35, then left 50 before hitting the ground.
May all perished rest in peace.
Join Date: Jul 2011
Location: Offshore
Age: 73
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
Plenty is known about the ATR's icing behaviour.
What is alleged so far... probable icing conditions..aircraft not de-iced... aircraft rolls one way and then the other...
IMHO probability that rolling was uncommanded and started at about t/o flap retraction... maybe a Ppruner with ATR experience could clarify t/o and flap-retraction procedures? Hoping this isn't another lax discipline/poor airmanship tragedy. TP
IMHO probability that rolling was uncommanded and started at about t/o flap retraction... maybe a Ppruner with ATR experience could clarify t/o and flap-retraction procedures? Hoping this isn't another lax discipline/poor airmanship tragedy. TP
Originally Posted by talkpedlar
Plenty is known about the ATR's icing behaviour.
Wait for CVR/FDR readouts. Sensible and useful discussion can start once they're published. MAK has lately been noted for some quick and accurate investigations.
Join Date: Mar 2007
Location: UK
Posts: 34
Likes: 0
Received 0 Likes
on
0 Posts
T/O Flap Retraction and Icing Speeds
Take off flap is 15 degrees.
At "Acceleration Altitude" the "Climb Sequence" is initiated. The nose is lowered with a climb airspeed of 170 Knots set in the ATR 72 (some companies use 180 Knots) and the power management system set to climb (from take off). With the lower nose attitude the aircraft should accelerate ready for flap retraction.
The airspeed for flap retraction depends on whether the aircraft is in "Normal" or "Icing" conditions. In "Normal" conditions on reaching "White Bug" speed the flaps are retracted, but in "Icing" conditions this is delayed until reaching the higher "Red Bug" speed.
"High Bank" is selected at White or Red Bug plus 10 knots depending on whether operating in Normal or Icing conditions respectively.
Per ATR "Icing conditions" are expected when air temperature is less than 7 degrees Celsius and there is visible moisture in the air, etc, etc.
"White" and "Red" bug speeds are determined from the charts dependent on take off weight.
Typically for the ATR 72 at, say, 20 tonnes the speeds are:
White Bug = 134 Knots
Red Bug = 161 Knots
If all the speeds, anti-icing and de-icing procedures are followed then the ATR 42/72 is perfectly safe in cold weather operations.
At "Acceleration Altitude" the "Climb Sequence" is initiated. The nose is lowered with a climb airspeed of 170 Knots set in the ATR 72 (some companies use 180 Knots) and the power management system set to climb (from take off). With the lower nose attitude the aircraft should accelerate ready for flap retraction.
The airspeed for flap retraction depends on whether the aircraft is in "Normal" or "Icing" conditions. In "Normal" conditions on reaching "White Bug" speed the flaps are retracted, but in "Icing" conditions this is delayed until reaching the higher "Red Bug" speed.
"High Bank" is selected at White or Red Bug plus 10 knots depending on whether operating in Normal or Icing conditions respectively.
Per ATR "Icing conditions" are expected when air temperature is less than 7 degrees Celsius and there is visible moisture in the air, etc, etc.
"White" and "Red" bug speeds are determined from the charts dependent on take off weight.
Typically for the ATR 72 at, say, 20 tonnes the speeds are:
White Bug = 134 Knots
Red Bug = 161 Knots
If all the speeds, anti-icing and de-icing procedures are followed then the ATR 42/72 is perfectly safe in cold weather operations.
Join Date: Mar 2007
Location: UK
Posts: 34
Likes: 0
Received 0 Likes
on
0 Posts
We will have to wait to see the full report before we can speculate as to what actually happened to those poor guys.
ATR gear retraction usually comes as soon as you have positive climb which is much lower than the quoted 210 m (=approx 680 feet).
Many ATR operators set "Acceleration Altitude" at 1,000 feet above aerodrome level, but this will vary according to operator, obstacles, noise abatement, etc, etc.
As mentioned in my earlier post, it is at "Acceleration Altitude" that you lower the nose, speed up and then retract flaps.
ATR gear retraction usually comes as soon as you have positive climb which is much lower than the quoted 210 m (=approx 680 feet).
Many ATR operators set "Acceleration Altitude" at 1,000 feet above aerodrome level, but this will vary according to operator, obstacles, noise abatement, etc, etc.
As mentioned in my earlier post, it is at "Acceleration Altitude" that you lower the nose, speed up and then retract flaps.
Last edited by Flying Beancounter; 3rd Apr 2012 at 10:47. Reason: clarity
Join Date: Apr 2012
Location: Miami, FL
Age: 31
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
similar crashes
The first officer survived. I want to see what he has to say. I don't know the background of the pilots of this accident, but it's usually pilots of old Russian airplanes that just upgraded to these newly acquired ATRs. I'm speculating by saying this about Russian pilots, however that's how it works in Cuba. In 2010 an ATR-72-212 operated by Aerocaribbean (CRN883), a Cuban airline, had an accident caused by a series of factors that took place. Icing condition was a factor, and pilot error was another factor. The captain, had a lot of experience in An-24 airplanes, which are old Russian turboprops that still operate in the island. The crew followed ATC instructions by banking to the right while he had an existing icing condition. By banking to the right he would be able to descend without the risk of colliding with a climbing airplane at 12 'O clock. When he banked, he stalled and got into a spin. He should have known better. He had already lost enough lift because of the ice buildup in the leading edge of the wings. Banking made the airplane loose more lift and stall. Complacency or poor training could have been a factor in his error.
Join Date: Apr 2012
Location: Miami, FL
Age: 31
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Certain types of air crashes usually repeat themselves. If it is determined that Utair flight 120 crashed with icing conditions, it should be the third case already. However it seems that the crash was controlled somehow, because there were some survivors. In the case of flight CRN883 , the airplane fell from 22,000 feet in a spin and there were no survivors. Airplane touched the ground flat as if it fell completely vertical. Flight 120 looks more like there was an attempt to control the crash and some control was gained.
When looking at the wreckage this appears not to have been a very high energy impact.
The exact wreckage pattern is difficult to dtermine from the pictures seen so far, however what can be seen seems to point towards some knd of rotation/cartwheeling upon impact. It does not really look like a fast straight- in crash.
Therefore, the likelyhood that some kind of aerodynamic stall was involved here appears to be high when looking at the wreckage.
Banking heavily left and right also matches a typical behaviour in stalled ATR's.
The exact reason for the stall will only be descernable from the FDR/CVR especially based on the respective speeds and loads.
Going by ATR's history however, it would not exactly be the first case of an iced over ATR biting the pilots.
The exact wreckage pattern is difficult to dtermine from the pictures seen so far, however what can be seen seems to point towards some knd of rotation/cartwheeling upon impact. It does not really look like a fast straight- in crash.
Therefore, the likelyhood that some kind of aerodynamic stall was involved here appears to be high when looking at the wreckage.
Banking heavily left and right also matches a typical behaviour in stalled ATR's.
The exact reason for the stall will only be descernable from the FDR/CVR especially based on the respective speeds and loads.
Going by ATR's history however, it would not exactly be the first case of an iced over ATR biting the pilots.
The wreckage is quite similar to the CO DC9 at Den back in the 80's.(failed to deice)
That plane did a snap roll left shortly after ground effect and continued the roll until it ended up on its back. The left wingtip remaoined in constant ground contact through the roll leaving "C" pattern in the snow.
The nose of the aircraft eventually dropped through this roll and impacted about 30 deg nose down. It was survivable depending on where you sat (little fire on top of the snow)
That plane did a snap roll left shortly after ground effect and continued the roll until it ended up on its back. The left wingtip remaoined in constant ground contact through the roll leaving "C" pattern in the snow.
The nose of the aircraft eventually dropped through this roll and impacted about 30 deg nose down. It was survivable depending on where you sat (little fire on top of the snow)
Join Date: May 2004
Location: 3.5 from TD
Age: 47
Posts: 1,042
Likes: 0
Received 0 Likes
on
0 Posts
Whose fault it was is not known
Join Date: Apr 2012
Location: Russia
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
As with everything you read in Russia take it with a BIG pinch of salt.
Vested interests are everywhere as usual.
Who isn't to say something was not functioning at TJM that morning PREVENTING a normal de-ice op.
Remember the TU RA-85744 that (hard) landed at DME with just about 1 functional engine,-
..Blaming the fuel, the plane, anything except the crew, who eventually it turns out inadvertently turned off the fuel supply while taking off.
The blame lies at the door of a whole safety culture, or lack of it, and that goes all the way to the top through the same systemic corruption that allows people to fry in a night club for lack of fire safety.
Lame Horse fire - Wikipedia, the free encyclopedia
So:-
You get on a freezing aircraft at 5am in a Russian regional airport.
Who are you to know the atmospheric conditions are ideal for icing, or your plane (RA-85588) is just about to catch fire?
.. or your pilot (RA-42434) is on meds that mean he gets confused at to what plane he is flying..
..or SU821 (has had a quick shot of vodka then starts swearing instead of proper CRM then turning to left when ATC ask to turn right, or missing the glide path altogether).
Vested interests are everywhere as usual.
Who isn't to say something was not functioning at TJM that morning PREVENTING a normal de-ice op.
Remember the TU RA-85744 that (hard) landed at DME with just about 1 functional engine,-
..Blaming the fuel, the plane, anything except the crew, who eventually it turns out inadvertently turned off the fuel supply while taking off.
The blame lies at the door of a whole safety culture, or lack of it, and that goes all the way to the top through the same systemic corruption that allows people to fry in a night club for lack of fire safety.
Lame Horse fire - Wikipedia, the free encyclopedia
So:-
You get on a freezing aircraft at 5am in a Russian regional airport.
Who are you to know the atmospheric conditions are ideal for icing, or your plane (RA-85588) is just about to catch fire?
.. or your pilot (RA-42434) is on meds that mean he gets confused at to what plane he is flying..
..or SU821 (has had a quick shot of vodka then starts swearing instead of proper CRM then turning to left when ATC ask to turn right, or missing the glide path altogether).
Join Date: Apr 2008
Location: Guernsey / Sussex
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
Many TP companies use an acceleration altitude above what was achieved in this accident but my ATR buddy tells me that the ATR manufacturer's procedure is to retract flaps at 400' agl. Given the time to call it, make the selection and for the flaps to travel, the maximum of achieved 680' could tie in with the result of no flaps on an iced-up wing.
If everybody else was de-icing that morning then so should have the ATR but reports do indicate it was not. The captain is 100% responsible for the de-ice/no de-ice decision as as for the suggestion de-icing may not have been available, that's no excuse you just don't take-off - simples!
From what has been said so far it does sound like a loss of control with a low speed/high descent rate impact. Lots of conjecture and no surviving crew so we'll have to wait for the FDR/CVR to tell us what really happened.
If everybody else was de-icing that morning then so should have the ATR but reports do indicate it was not. The captain is 100% responsible for the de-ice/no de-ice decision as as for the suggestion de-icing may not have been available, that's no excuse you just don't take-off - simples!
From what has been said so far it does sound like a loss of control with a low speed/high descent rate impact. Lots of conjecture and no surviving crew so we'll have to wait for the FDR/CVR to tell us what really happened.
Join Date: Apr 2012
Location: Russia
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
"de-icing may not have been available, that's no excuse you just don't take-off - simples!"
Not so simple in Russia.
Lot's of pressure often brought to bear/connecting flights/return slots, plane has to fly on time, or maybe won't fill the quota for the day where distances can be large.
What I don't understand is any pressure to be "on time at all costs" on this flight.
There are NO connecting flights in the SGC arrivals time slot.
(in fact nothing at all from 10-16h)
& the same plane UT119 flies back at 22h in the evening to TJM, or so it would seem, so sits on the tarmac from 23.45-6.30 every night.
Maybe PF says/thinks he's done this loads of times before and got away with it, esp on AN type AC, so cutting corners.
Would be curious to know how many times this winter the plane DIDN'T get deiced in the morning after sitting in anything down to -45C.
That would be very telling.
Culture of Safety taking back seat to commercial considerations?
Still the most dangerous country to fly in the world.
Not so simple in Russia.
Lot's of pressure often brought to bear/connecting flights/return slots, plane has to fly on time, or maybe won't fill the quota for the day where distances can be large.
What I don't understand is any pressure to be "on time at all costs" on this flight.
There are NO connecting flights in the SGC arrivals time slot.
(in fact nothing at all from 10-16h)
& the same plane UT119 flies back at 22h in the evening to TJM, or so it would seem, so sits on the tarmac from 23.45-6.30 every night.
Maybe PF says/thinks he's done this loads of times before and got away with it, esp on AN type AC, so cutting corners.
Would be curious to know how many times this winter the plane DIDN'T get deiced in the morning after sitting in anything down to -45C.
That would be very telling.
Culture of Safety taking back seat to commercial considerations?
Still the most dangerous country to fly in the world.