One down in Mexico
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From: UK
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From: se england
To say nothing of any passengers in the van, it is almost unbelievable how the rotor blades didnt chop it to pieces before he managed to accelerate away .
Lot of people thanking lucky stars after that
Lot of people thanking lucky stars after that
Joined: Mar 2002
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From: England
It does look that way but until it hits the ground I don't see anything untoward from the TR slowing down or moving unnaturally. Looking at his manoeuvre I wonder if he was heavy, hot n high and put a bootful of rudder in as he came to the hover and just ran out of tail rotor authority? Just a guess....
Last edited by SimonK; 27th August 2021 at 12:40.
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From: Mesopotamos
Regarding running out of anti-torque pedal, I stumbled across this post from long ago by Nick Lappos which is worth a repost.
Whatever the issue in that video, I think the pilot, after realising he was in trouble low down, went for the paddock when out of nowhere comes a bus full of tourists and it's too late. Glad there were no major injuries.
If you slip down in Nr by even a bit, it can have a double effect. Here's why:
The thrust you deliver from the tail rotor creates the anti-torque, and is proportional to the pitch setting and the square of the Nr. If you reduce Nr by 2%, you reduce the thrust by 4%, which could get you close to limits in some cases.
The anti-torque that you need is proportional to the main rotor torque. If you droop Nr, the rotor needs the same power, but power is torque times Nr, so for constant power, the Main Rotor torque must go up. For a 2% droop in Nr, the torque will rise by 2%, and the anti-torque needed wil have to rise.
Thus, a given droop in Nr produces non-linear effect on the tail rotor margin.
A third effect is the need for the helicopter to point into the wind, like a weathervane. When crosswind, this effect is maximized.
Another effect that can play is vertical maneuvering. Note that a slight torque rise (manifold pressure for recips) will require a corresponding anti-torque response to maintain heading. If you nudge the collective upward and droop the Nr a bit, you can easily carve 5 or 7 knots off the side flight capability of the machine. For a hairy flare at the bottom of a too-fast approach, the main torque can be pumped to 10 or 15% above hover torque, and the tail rotor can be saturated.
There really is no such thing as Loss of Tail Rotor Effectiveness, BTW - for a given density altitude, the tail rotor always produces a given maximum amount of thrust and a given maximum effectiveness, it is just that it can be swamped by main rotor torque rises, and by crosswind effects. Generally, only marginal tail rotors experience LTE, and the vast majority of LTE events are experienced by only two types of helicopter. LTE is not a pervasive helicopter problem.
The thrust you deliver from the tail rotor creates the anti-torque, and is proportional to the pitch setting and the square of the Nr. If you reduce Nr by 2%, you reduce the thrust by 4%, which could get you close to limits in some cases.
The anti-torque that you need is proportional to the main rotor torque. If you droop Nr, the rotor needs the same power, but power is torque times Nr, so for constant power, the Main Rotor torque must go up. For a 2% droop in Nr, the torque will rise by 2%, and the anti-torque needed wil have to rise.
Thus, a given droop in Nr produces non-linear effect on the tail rotor margin.
A third effect is the need for the helicopter to point into the wind, like a weathervane. When crosswind, this effect is maximized.
Another effect that can play is vertical maneuvering. Note that a slight torque rise (manifold pressure for recips) will require a corresponding anti-torque response to maintain heading. If you nudge the collective upward and droop the Nr a bit, you can easily carve 5 or 7 knots off the side flight capability of the machine. For a hairy flare at the bottom of a too-fast approach, the main torque can be pumped to 10 or 15% above hover torque, and the tail rotor can be saturated.
There really is no such thing as Loss of Tail Rotor Effectiveness, BTW - for a given density altitude, the tail rotor always produces a given maximum amount of thrust and a given maximum effectiveness, it is just that it can be swamped by main rotor torque rises, and by crosswind effects. Generally, only marginal tail rotors experience LTE, and the vast majority of LTE events are experienced by only two types of helicopter. LTE is not a pervasive helicopter problem.
Joined: May 2002
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From: Wanaka, NZ
No way. Loss of TR drive would result in a much faster rotation than what is seen in the video. I'm with megan on this one, he ran out of pedal.
Joined: Sep 2005
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From: Montreal
Heavy, aborted takeoff, stopped and turned out of any wind while still 'way out of ground effect. Settled with power, kept pulling the NR down so consequent loss of tail rotor authority and uncontrolled rotation. Might have made it without that pesky van in the way.
Thought the takeoff point was the football pitch, and the paddock with van was just a convenient place to crash.
mexico, previous ride might have been a 407, and he would have gotten away with it in that.
Thought the takeoff point was the football pitch, and the paddock with van was just a convenient place to crash.
mexico, previous ride might have been a 407, and he would have gotten away with it in that.
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From: On the green bit near the blue wobbly stuff
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From: EU
It looks like the pilot reduced power after the initial take off and the yaw reduced mostly (sideslip helping keep it straight). Wonder if he might have been able to fly that out tbh, but he slowed to put it down with increasing yaw again. Hard to watch and not shout “keep it down” after that first ground contact.
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From: Aus
we can't all be Chuck Yeager
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From: Pensacola, Florida
Ohhh, dear Megan. Close out Tik Tok for a moment, will you? Look sweetie, you have to take into consideration the totality of C. Yeager's life and accomplishments. I realize that they all happened well before you were born, and so therefore don't count, something that is typical among you millennials. (Hell, for that matter the Beatles happened before you were born, too, and you probably consider BTS to be cutting edge.) And so you took one screwup of Yeager's and used that to invalidate his whole career and equate it with that of some bonehead helicopter pilot who couldn't fly his way out of an LTA event, eh? That about right, missy?
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From: On the big blue planet
skadi
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From: EU
Looks like he should have aborted the landing a bit more.