Russian Helicopter sea accident
Psychophysiological entity
Joined: Jun 2001
Aviation Qualifications: ATPL
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From: Walton on the Naze Essex.
It looks like a blade perturbation took a good part of the tails structure away before other stresses snapped it completely. Not that it would have made much difference.
The gear does seem to be down, and it may be that the pilot was hoping for more forward movement through the water, even up to the plane?
The gear does seem to be down, and it may be that the pilot was hoping for more forward movement through the water, even up to the plane?
Joined: Apr 2004
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From: NO GPS FIX
From what I saw the forward floats have completely failed to inflate.
The round item that's seen near the nose looks like a fixed cowl around a radar or something of the sort.
It explains the very rapid nosing over of the aircraft.
bb
P.S. If you haven't done Helicopter Underwater Escape Training before or recently make sure you get a course.
The round item that's seen near the nose looks like a fixed cowl around a radar or something of the sort.
It explains the very rapid nosing over of the aircraft.
bb
P.S. If you haven't done Helicopter Underwater Escape Training before or recently make sure you get a course.
Joined: Jul 2005
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From: highlife
Maybe?
Blades on the machine appear to rotate to the right. The machine is twin eng. An eng failure in the hover without enough pwr to hover OEI would result in rotor bleed and descent (explains the coning angle and yaw to the right as airframe yaws in the direction of M/R drag, ie at high coning angle t/r can no longer balance m/r TQ).
If the machine suffered a loss of t/r or insufficient t/r thrust in the the hover then it would yaw left (video shows yaw to right). Excessive t/r thrust fixed pitch would result in machine yawing right and continuing to yaw right unless collective lowered, pitch on blades indicates machine had high collective setting on touch down which indicates machine went right without lowering collective-Therefore t/r malfunction unlikely.
Hard landing may have damaged belly and underside of machine, floats etc, as a result machine started to take on water, CG changed (more weight in nose cone due water). Pilot attempts to fly away OEI while taking on water, aircraft capsizes as pitch is applied and nose becomes too heavy. Main rotor contact with water and airframe destruction results.
Summary-Aircraft conducting OGE hover OW, ENG fail, Aircraft now OEI with insufficient power to fly away from hover, RRPM decay, M/R drag increases and aircraft yaws right, co-incident with aircraft touching down with large ROD, underside/undercarriage damaged, aircraft takes on water, aircraft CG changes (nose heavy), Pilot attempts to fly away OEI as machine starts to take on water, Power available < power required, aircraft rotates foward-M/R contact with water-Resultant crash....
My 2 cents.
Condolences to family members
Lasty
If the machine suffered a loss of t/r or insufficient t/r thrust in the the hover then it would yaw left (video shows yaw to right). Excessive t/r thrust fixed pitch would result in machine yawing right and continuing to yaw right unless collective lowered, pitch on blades indicates machine had high collective setting on touch down which indicates machine went right without lowering collective-Therefore t/r malfunction unlikely.
Hard landing may have damaged belly and underside of machine, floats etc, as a result machine started to take on water, CG changed (more weight in nose cone due water). Pilot attempts to fly away OEI while taking on water, aircraft capsizes as pitch is applied and nose becomes too heavy. Main rotor contact with water and airframe destruction results.
Summary-Aircraft conducting OGE hover OW, ENG fail, Aircraft now OEI with insufficient power to fly away from hover, RRPM decay, M/R drag increases and aircraft yaws right, co-incident with aircraft touching down with large ROD, underside/undercarriage damaged, aircraft takes on water, aircraft CG changes (nose heavy), Pilot attempts to fly away OEI as machine starts to take on water, Power available < power required, aircraft rotates foward-M/R contact with water-Resultant crash....
My 2 cents.
Condolences to family members
Lasty
Joined: Dec 2000
Aviation Qualifications: ATPL
Posts: 1,271
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From: Various
If one of the forward windows blew in, against the force of the water on it........?
The other thought is that with the nose so low under water, the angle between the centre of the rotor and the pivot point (usually the C of G but now the nose) is very different and might have tripped the heli up. Rather like pushing a wheelbarrow with all the weight at the front and then hitting a large stone with the tyre.
Than god that I failed the Bristow helicopter course. We don't do that sort of flying in a 767!
The other thought is that with the nose so low under water, the angle between the centre of the rotor and the pivot point (usually the C of G but now the nose) is very different and might have tripped the heli up. Rather like pushing a wheelbarrow with all the weight at the front and then hitting a large stone with the tyre.
Than god that I failed the Bristow helicopter course. We don't do that sort of flying in a 767!
Joined: Dec 2001
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From: England
To me it looked like he was trying to taxi into wind/current. It looks like he had a lot of forward cyclic on. Then had a dynamic roll over due to reaching the stops. Has this ever been done forwards before?
http://www.nps.navy.mil/avsafety/gouge/rollover.htm
http://www.nps.navy.mil/avsafety/gouge/rollover.htm
Joined: Feb 2006
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From: On the big blue planet
@last third
In my opinion You are right. Due to the hard OEI landing in the water, the belly ore the Radardome must have been damaged and the H/C took water. Check the high waterline just before the MR struck the water.... And in addition the extended Landinggear also made an SingleEngineWaterTakeoff ( a procedure like with a seaking or S61 ) much harder or even impossible.
skadi
In my opinion You are right. Due to the hard OEI landing in the water, the belly ore the Radardome must have been damaged and the H/C took water. Check the high waterline just before the MR struck the water.... And in addition the extended Landinggear also made an SingleEngineWaterTakeoff ( a procedure like with a seaking or S61 ) much harder or even impossible.
skadi
Joined: Jun 2004
Posts: 646
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From: Europe
Float bags were inflated prior to water landing. Lots of coaning on main rotor blades - low rpm. That is clear as todays blue sky.
The thing that bothers me is, why did the pilot try to takeoff again if he was having problems.
Why attempt a SE water take off? There are plenty of ships handy.....he could have off loaded the pax or even burnt off fuel while sitting on the water.....or even elected to make a slow water taxi to suitable land?
Alba Gu Brath
Joined: Oct 2000
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From: Merseyside
Just a thought, no more. Looking at the video the heli looks fairly unstable in the water, perhaps due to the swell. Could it be that the sea was not calm enough to allow him to remain there and he elected to get airborne?
Joined: Nov 2005
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From: somedays in a helicopter, other days in a fixed-wing....
http://www.sky.com/skynews/picture_g...1423-3,00.html - This is the impact photo
http://www.sky.com/skynews/picture_g...1423-4,00.html This is the water surging over nose
http://www.sky.com/skynews/picture_g...1423-5,00.html This is where the blades impact
http://www.sky.com/skynews/picture_g...1423-6,00.html This shows the helicopter upside down. in this photo there doesn't appear to be visible damage to the under side of the aircraft. Eg: Radar, Floats etc, although it is clear the gear is down.
(i'm not an expert in taking off form water in multi-engine helicopters)
would it be right for one to assume in that sort of situation where water surges over the nose so violently, you would lower collective..decrease power.Abort the T/O attempt ? As you would do for dynamic roll over ? i only state this to learn about the procedures in this sort of situation ?
http://www.sky.com/skynews/picture_g...1423-4,00.html This is the water surging over nose
http://www.sky.com/skynews/picture_g...1423-5,00.html This is where the blades impact
http://www.sky.com/skynews/picture_g...1423-6,00.html This shows the helicopter upside down. in this photo there doesn't appear to be visible damage to the under side of the aircraft. Eg: Radar, Floats etc, although it is clear the gear is down.
(i'm not an expert in taking off form water in multi-engine helicopters)
would it be right for one to assume in that sort of situation where water surges over the nose so violently, you would lower collective..decrease power.Abort the T/O attempt ? As you would do for dynamic roll over ? i only state this to learn about the procedures in this sort of situation ?
Joined: May 2004
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From: warsash
d246, I do hope you're not a crash investigator. I flew the USCG HH52 (one- engined mini-SeaKing) back in the 80s and practised a fair bit of rescue work on the water. By reputation the Hip/Haze is a robust aircraft with reasonable performance margins (better than the SeaKing). This guy had a lot of people on board, he was overpitching to achieve a take-off and then appears to settle back heavily into the water after that aborted lift-off (water ingress into cabin at that point would have been likely). He had perhaps lowered his undercarriage whilst waterborne to give him better stability (or it extended after the crash). He then appears to water-taxi so fast trying to unstick that he was enveloped by his bow-wave and pitchpoled. The paradox is that if he'd gone a tad faster the bow-wave would have swamped both engine intakes, put the fires out and, perhaps, sustained less blade impact damage. Either way, it was a hard day in the office for this guy and it was a tragedy that a life was lost.
That's Life!!
Joined: Feb 2004
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From: Out of the sand pit, carving a path through our jungle.
I believe that last third is about spot on, apart from maybe the machine taking on water, I suspect he was way over weight to attempt OEI take-off (impact following possible engine failure was heavy).
jetflite, absolutely correct, you would lower collective and abort, at least I would!
Why didn't he shut down and abandon ship? (face-saving, perhaps?).
jetflite, absolutely correct, you would lower collective and abort, at least I would!
Why didn't he shut down and abandon ship? (face-saving, perhaps?).
Joined: Feb 2005
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From: uk
The cone angle can only be explained by high pitch and v low rotor rpm, a single or possibly dual engine failure. The torque goes of the clock if you try taking of overweight, the blades don't behave like that. There would be no usable head energy once on the water to attempt anything.
Joined: Nov 2004
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From: South east England
Could the initial impact have been caused by vortex ring state? Its looks like he is sinking under power and the coning extreme happens just as he is about to hit the water. Im not sure what happens to a machine when in VRS as it approaches the ground? It looks similar to the Sea king accident that happened at a UK airshow. Then the Helo hit the ground hard and the structure failed, causing tail rotor failure and destruction.
Quite agree with the movement of the CG but surely if he was moving forward the water taken on-board would have moved back-wards causing a tail down attitude! WE will never know until the investigation is complete but condolences to the Families.
Flash
Quite agree with the movement of the CG but surely if he was moving forward the water taken on-board would have moved back-wards causing a tail down attitude! WE will never know until the investigation is complete but condolences to the Families.
Flash
Joined: Jul 2002
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From: Denver, CO and the GOM
Originally Posted by Flashover999
Could the initial impact have been caused by vortex ring state?
Joined: Oct 2002
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From: scotland
Totally agree with Last Third. Even the Sea King leaks when dunked, the advice is to attempt an OEI take-off sooner rather than later. Two reasons, CofG change usually nose heavy, and stab electronics are in the nose so would be soaked pretty quickly. Bearing in mind leakage occurs on serviceable machines an impact like this one had would almost certainly lead to water ingress.
A take-off in this state is a recognised procedure and I doubt if our unfortunate pilot would be able to conjure up an acceptable weight figure whilst sat on the water. He tried an acceptable manoeuvre and it went wrong, for what reason we cannot be sure. I think most of us have been there and been lucky.
Lets not blame a pilot for doing what he is trained to do, lets learn where it went wrong and hopefully be better equipped to deal with that situation if we are ever unfortunate enough to be there.
A take-off in this state is a recognised procedure and I doubt if our unfortunate pilot would be able to conjure up an acceptable weight figure whilst sat on the water. He tried an acceptable manoeuvre and it went wrong, for what reason we cannot be sure. I think most of us have been there and been lucky.
Lets not blame a pilot for doing what he is trained to do, lets learn where it went wrong and hopefully be better equipped to deal with that situation if we are ever unfortunate enough to be there.
Joined: Feb 2006
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From: In my Hammock or at the Pub!
Originally Posted by d246
..... a single or possibly dual engine failure. ...
Mate you can't water taxi with zero engines working. The clip cleary shows the machine attempting a water take off post impact, trying to do this with zero engines operating is a tad diifficult. Hence dual engine failure, I think not.
Max
