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Action gt stall


clivefreeman
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Same scenario as the other vid with FT pilot crashing to ground.

Wing naturally turning to right under full power climbout (he should have left it hands up while it climbed, or weight shift / tiny bit of brake just to hold it straight).

High AoA due to full power, brings wing closer to stall point.

Pilot then uses hefty amount of brake to try to turn left, fighting the right hand turn.

Left side of wing stalls, collapses - too low to recover so the rest is history ..... :cry:

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What hapened here then, pilot was ok but a bit bruised.

Could of been alot worse. There was zero wind and he only aplies brake to turn left, against the torque. Is this the reason for the stall.

[youtubevideo]

[/youtubevideo]

The left hand side of the wing is at full reflex! the right hand side is fully closed, pulling that much brake in full reflex is what caused the wing to stall, I have done this myself, but I was on a small wing with a high loading and just flew round in a circle, in disbelief at how stupid I had been! I just pulled the trims back in and off I went..

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Same scenario as the other vid with FT pilot crashing to ground.

Wing naturally turning to right under full power climbout (he should have left it hands up while it climbed, or weight shift / tiny bit of brake just to hold it straight).

High AoA due to full power, brings wing closer to stall point.

Pilot then uses hefty amount of brake to try to turn left, fighting the right hand turn.

Left side of wing stalls, collapses - too low to recover so the rest is history ..... :cry:

Have to agree with you, just been watching it in slow mo. Too much brake on left side on climbout

. And unfortunatley flying an action gt

Thanks Clive

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Can't see the trailing edge brilliantly well, but I think both brakes were applied, the left hand more so.

Perhaps the brake lines were not adjusted to give enough slack with hands up. The wing was definately being slowed down, on climb out it should be no brakes or just a little on one side to keep the wing flying straight.

Wing was slowed down so much that a stall was inevitable IMHO.

Alan

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I was flying ten minuites before hand and saw it hapen. We checked the brakes and take of position of trimers all was normal. He walked away from it but was well shaken up, luckily enough he landed in nice soft ploughed mud.

Hes right hand was definatley up at all times.

The parajet took a beating, on coming down he was spiraling down very quick.

He is now considering a new synthesis if he decides to fly again.

But hes said that he will not fly the gt again.

Thanks Clive

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@ 19s in HD it is evident that there is significant deformation on the right trailing edge, but it's not evident that there was a lot of brake application on that side. I think we all agree airspeed was too low due to the outcome, but why is the thing that would be good to understand. Pilot can speak to it, but the rest of us are guessing.

Energy management failure.

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Well I think the reasons have been explained (even though it is educated guessing) and I stand by my earlier post. Often even the pilot may not fully understand the reason (hence why the accident happens) but if you read the advice / warnings from the Action GT manual it certainly describes what I can see in the video.

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when it zooms in just after he leaves the ground it does look like a bit of brake is being applied, it looks like the wing never gained any real airspeed before he applied the brakes to turn.

I agree outcast, both brakes (including right) appear to remain on during and after take off evidenced at the trailing edge, the wing never reaching true flying speed before the pilot attempted a turn agianst torque at full power / AOA.

The GT is an advanced wing not for novice pilots. How many hours / take off's had the pilot achieved at this point? Normally feedback through the brake lines should inform the pilot the flying state of his wing if he has sufficient unconscious competence to take in this information during a critical phase of flight like take off.

I had a similar thing happen to me in 2006 but after a streight climb out and at 800 ft. The cause turned out to be knots in my D risers which I missed during pre-flight checks and post take off check. I had a turn which I ignored and when the left wing collapsed I failed to execute the correct proceedure to get the wing flying again. On landing I immediately bundled the wing up and sent it to the loft for inspection. They found the knots in the D lines.

Prior to the loft inspection providing the cause of collapse I spoke to wing designers describing what had happened. I was informed that under power it is possible to achieve take off with the wing in the partial stall, hanging back not achieving true airspeed. In this state any attempted menouvre may induce a stall on the side of the input.

I believe this type of situation is common in all paramotor wings not just one make!!

As for executing recovery proceedure I attempted to pump out the collapsed wing with the brakes which induced a full stall on both sides :shock: I was informed that the best proceedure was to pull on the A risers to get the wing flying again which makes sense as this is how we get the wing inflated when ground handling. Obviously the chap in the vid did not have the time / height to attempt anything other than a brace for PLF.

Its good to share thoughts ideas and experiences both good and bad.

Regards.

Whitters.

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