Airshow Crash Russia
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Cant pretend I know anything about that particular machine, But if they are talking about hydraulics, maybe there was some sort of control restriction preventing movement of the collective?
Good spot RC but half way down, it reverses the direction of spin???
Maybe because of pilot input? The authorities are talking about hydraulic problems (input shaft servo)? Look at that TR on the way down.
What is debatable is why he didn't cushion the touchdown sufficiently.
If I recall correctly didn't the same happen to AG +1 in a Gaz piece @ Predannack local area at the top of a wing over?
As previously mentioned dumping the lever and nudging it fwd for speed should have helped enormously with the end result.
Maybe the revolutions were enough to disorientate the HP upsetting his decision point just above touchdown??
God knows how the other guy survived
Maybe because of pilot input? The authorities are talking about hydraulic problems (input shaft servo)? Look at that TR on the way down.
What is debatable is why he didn't cushion the touchdown sufficiently.
If I recall correctly didn't the same happen to AG +1 in a Gaz piece @ Predannack local area at the top of a wing over?
As previously mentioned dumping the lever and nudging it fwd for speed should have helped enormously with the end result.
Maybe the revolutions were enough to disorientate the HP upsetting his decision point just above touchdown??
God knows how the other guy survived
Looks like a TR servo hardover since it is yawing left at a constant rate throughout - it appears the pilot had sufficient lever in to control the RoD and maintain a manageable rate of rotation.
He was probably trying to diagnose the problem all the way down and just misjudged the point he needed to cushion the touchdown - he had spun round enough times to be disorientated.
He was probably trying to diagnose the problem all the way down and just misjudged the point he needed to cushion the touchdown - he had spun round enough times to be disorientated.
Certainly looks like a TR failure, and once you get going vertically, it seems to be difficult to get out of while spinning. If you look at the rotor wash created at impact, it looked as though the pilot had pulled an arm full of collective, but just a bit late. Having flown displays while doing this exact maneuver, I find VRS very unlikely. But the lack of effectiveness of the cushion could likely be attributed to VRS as the pitch was pulled. One thing to remember is, once a TR failure starts to spin, it will continue to spin due to inertia until forward airspeed or drag stops it. Even with collective full down and no torque. You can see that the rotational acceleration ceases very quickly and it descends at a very constant yaw rate once established. Those are just my observations!
Non-PC Plod:
Again a visual deception because of the frame rate. Looking at pictures you will find that the Havoc has clockwise rotating blades, like most (all?) Russian helicopters.
The helicopter comes down yawing in the same direction as the rotor blades are spinning.
Avoid imitations
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Unless that type has a "puller" tail rotor, it wasn't opposing the main rotor torque once established in the descent.
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Russian vs UK/US rotor spin
I too may be a bit thick; but since UK/US aircraft yaw right when tail rotor thrust is lost, shouldn't Russian (& French) aircraft yaw left when they lose tail rotor thrust? Regardless of the frame rate, it appears that the tail rotor is not working as advertised. Also, once the yaw exceeds 90-180 degrees, attempts to lower the nose to gain airspeed and fly out of the spin just lead to unusual attitudes on impact - especially in large, heavy aircraft. This pilot displayed commendable discipline in maintaining a level attitude all the way to impact in order to use the crash attenuating features of the MI-28 to their best - the fact that one pilot actually survived and was able to stagger away is testimony to that.
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I believe the press report of hydraulic failure. The aircraft does not waver in its descent, and there is no attempt to recover in any way, including no pitch pull at the bottom. That is not a "normal" anti-torque failure, the spin rate is too slow. It has the hallmarks of a helo with locked controls trapped in a descent.
Not VRS, the descent is not fast enough.
The Mi-28 has side eject capability, with a bounce pad outside the door to prevent contact with the wings on bailout.
Not VRS, the descent is not fast enough.
The Mi-28 has side eject capability, with a bounce pad outside the door to prevent contact with the wings on bailout.
Locked Controls
Nick, re locked controls. As I recall you had a chance some time ago to get a thorough walk-around on a MIL-28. Question: They probably have at least two, if not three hydraulic pumps/reservoirs, so losing all hydraulics seems improbable? Video shows no input to the directional or collective controls, but the pitch and roll axes remain fairly level. Does that machine incorporate a collective/yaw mixer and could a mechanical failure therein explain the flight path?
You'll recall the UH-60 accident where the cause was finally determined to be a non-safetied bolt ( there had been maintenance performed by the unit ) in the control mixing unit that fell out and jammed the longitudinal control. Matching witness marks were found on the jammed parts.
In this case there is a survivor, so by now the detailed cause is most likely known.
You'll recall the UH-60 accident where the cause was finally determined to be a non-safetied bolt ( there had been maintenance performed by the unit ) in the control mixing unit that fell out and jammed the longitudinal control. Matching witness marks were found on the jammed parts.
In this case there is a survivor, so by now the detailed cause is most likely known.
