rotorheads, explain this wreck:

Let'sgoflying!

Let'sgoflying!

Touchdown! Greaser!
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Dave Taylor
cyclic forward, then collective up?
would a gust on the tail start this?
and pilot's response was to take-off again?

(Sure seems like it developed a bunch of lift after nosing over.)




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Well if you can't get that vid to load there is this one:
Looks to me that the blades remain flat at time of noseover, but what do I know about these aircraft?

 
Let'sgoflying! said:
cyclic forward, then collective up?
would a gust on the tail start this?
and pilot's response was to take-off again?
(Sure seems like it developed a bunch of lift after nosing over.)
Click to expand...

Only a low time heli pilot, but my guess is that this was no gust. It looks like the pilot (or passenger, possibly inadvertently) pushed the cyclic forward and/or the collective up.
The whitecaps in the background don't suggest any unusual wind, and the sudden rise of the tail has all the signs of being self-induced.
 
I'd agree with GD. Don't see this as a wind issue. If he were landing in that much wind to lift the tail, he'd be fighting it way more than that at a hover (weathercock instability). Maybe has 10-15 KT tailwind but nothing on the water would suggest anything above that. Plus, if the wind was that strong to lift the tail, you'd be a fool to try and land with a tailwind when the LZ obviously supports turning into the wind.

Someone smacked the cyclic forward and he pilot overreacted and got airborne again.
 
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RotorDude said:
Only a low time heli pilot, but my guess is that this was no gust. It looks like the pilot (or passenger, possibly inadvertently) pushed the cyclic forward and/or the collective up.
The whitecaps in the background don't suggest any unusual wind, and the sudden rise of the tail has all the signs of being self-induced.
Click to expand...

That's what I thought when I saw the video.

BTW... Like you I'm not a high time rotor guy, but I figure if it was a tailwind issue, the problem would have been weather cocking (the tail swinging around) as opposed to nosing over.
 
Anymouse said:
That's what I thought when I saw the video.

BTW... Like you I'm not a high time rotor guy, but I figure if it was a tailwind issue, the problem would have been weather cocking (the tail swinging around) as opposed to nosing over.
Click to expand...

Agreed, and as Velocity173 mentioned above, if there were any significant tailwind, he'd have turned into it before touchdown (though I can see why for safety they'd want the tail facing the sea normally).
 
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Looks like he set it down on the front of the skids and maybe tried to set the back of the skids down with the cyclic instead of reducing collective. Got a mast bump and away she went...


Or not.

Chris
 
Hiperbiper said:
Looks like he set it down on the front of the skids and maybe tried to set the back of the skids down with the cyclic instead of reducing collective. Got a mast bump and away she went...


Or not.

Chris
Click to expand...

You can't mast bump an Astar. That phenomenon applies to teetering systems such as R22 B206 aircraft. Astar uses a Starflex system which is similar to a fully articulated rotor head.

https://m.youtube.com/watch?v=PaSm3cor3wg
 
Looks like Hogg may have gotten a flying gig after all...certainly looks like his style.
 
Hydraulic (cyclic) hard over is my guess.
 
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Velocity173 said:
You can't mast bump an Astar. That phenomenon applies to teetering systems such as R22 B206 aircraft. Astar uses a Starflex system which is similar to a fully articulated rotor head.

https://m.youtube.com/watch?v=PaSm3cor3wg
Click to expand...

So it has no coning stops of any kind?

Looking back at the video in slo-mo does anyone else see a piece of something (looks like a rod of some sort) fly away from the helo @ the :17 sec mark? It looks to go from the helo to the top left corner of the video...

Chris
 
Hiperbiper said:
So it has no coning stops of any kind?

Looking back at the video in slo-mo does anyone else see a piece of something (looks like a rod of some sort) fly away from the helo @ the :17 sec mark? It looks to go from the helo to the top left corner of the video...

Chris
Click to expand...

The coning of the blades is absorbed by the composite yoke. The Starflex is similar to the Soft-In-Plane rotor on the B407 in that there aren't any mechanical flapping hinges but elastomeric bearings. There are flap stops and there are static stops when the blades come to a stop.

Mast bumping occurs in teetering semi-rigid systems where the blade flaps down violently and contacts the mast. In order to do that, you'd have to be at zero G with an aggressive cyclic input, or on the ground at flat pitch with an aggressive cyclic input.

Since the Astar's hub doesn't teeter around the mast, it can't "bump" it.
 
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"Looking back at the video in slo-mo does anyone else see a piece of something (looks like a rod of some sort) fly away from the helo @ the :17 sec mark? It looks to go from the helo to the top left corner of the video..."

Never mind; it's most likely the tip of one of the blades going around...


Chris

Vel173; you don't happen to fly a Velocity do ya?
 
Hiperbiper said:
"Looking back at the video in slo-mo does anyone else see a piece of something (looks like a rod of some sort) fly away from the helo @ the :17 sec mark? It looks to go from the helo to the top left corner of the video..."

Never mind; it's most likely the tip of one of the blades going around...


Chris

Vel173; you don't happen to fly a Velocity do ya?
Click to expand...

I do. Helicopters for work, Velocity for fun.
 
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