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An angel at my pad (Keck hospital rooftop crash)

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An angel at my pad (Keck hospital rooftop crash)

Old 7th Nov 2020, 09:22
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An angel at my pad (Keck hospital rooftop crash)

Thankfully no injuries and the organ they were transporting was still useable.
Thankfully it didn't fall off the building.

Anyone know how it ended up on its side?

https://www.dailynews.com/2020/11/06...pital-helipad/

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Old 7th Nov 2020, 09:28
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Old 7th Nov 2020, 10:40
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Looks like a TR drive failure from the witness video
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Old 8th Nov 2020, 13:26
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another angle

https://www.liveleak.com/view?t=9PUrn_1604775586
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Old 8th Nov 2020, 14:12
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I'd agree that looks like a T/R drive failure at the most critical stage of the landing. Looks like a quick and correct response by the pilot, namely by lowering the collective, bearing in mind there was little or no time to shut down the engines. Quite interesting to see how rapidly it rolled!

Glad to hear they all survived.
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Old 9th Nov 2020, 02:19
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The second video classed it as a "hard landing"!
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Old 9th Nov 2020, 14:02
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Originally Posted by ShyTorque View Post
Quite interesting to see how rapidly it rolled!
I was wondering whether the pilot had induced the roll in trying make sure of reaching the roof whilst yawing. Hard to control attitude and track once the yaw has developed.

Got it where it needed to be, all lived 👍
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Old 9th Nov 2020, 15:56
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Sure that this was a TR drive failure? I saw a longer video of the approach and the TR RPM didn't change during final and beginning of the rotation .

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Old 9th Nov 2020, 16:33
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Is this the same heli type that crashed in Leicester two years ago and if so, could it be the same issue?

Last edited by golfbananajam; 9th Nov 2020 at 16:34. Reason: typos corrected
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Old 9th Nov 2020, 17:11
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Originally Posted by golfbananajam View Post
Is this the same heli type that crashed in Leicester two years ago and if so, could it be the same issue?
The Leicester aircraft was an AW169. This was an AW109.
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Old 9th Nov 2020, 17:13
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T/R rpm looks steady..maybe los of tail rotor authority...what is the Density Alt etc?
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Old 9th Nov 2020, 17:14
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Sure that this was a TR drive failure? I saw a longer video of the approach and the TR RPM didn't change during final and beginning of the rotation .
If it wasn’t a driveshaft failure it must have been a hard right pedal input, or control runaway. It’s difficult to tell if the tail rotor rpm changed because we’re not watching in real time and camera frame rate masks what’s going on.

Originally Posted by golfbananajam View Post
Is this the same heli type that crashed in Leicester two years ago and if so, could it be the same issue?
As per the previous post, the aircraft are totally different types (169 versus 109) and their tail rotor control systems are totally different.
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Old 9th Nov 2020, 18:05
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Golly, you guys must be subject matter experts on the 109 Series TR Control system to be so sure of what happened.
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Old 9th Nov 2020, 18:46
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Originally Posted by Hueymeister View Post
T/R rpm looks steady..maybe los of tail rotor authority...what is the Density Alt etc?
DA pretty much sea level.
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Old 9th Nov 2020, 20:12
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Golly, you guys must be subject matter experts on the 109 Series TR Control system to be so sure of what happened.
Yep - just watch the video and pull up a comfy armchair.....
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Old 9th Nov 2020, 20:27
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The initial slow rate of rotation at loss of directional control does not look like sudden TR drive failure to me.
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Old 9th Nov 2020, 20:33
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Originally Posted by gulliBell View Post
The initial slow rate of rotation at loss of directional control does not look like sudden TR drive failure to me.
have you seen the video in post 4? I wouldn’t call that slow - it’s gets real busy real quick!
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Old 9th Nov 2020, 20:44
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It wasn't slow by the time it got to complete the first 360, but the rate of rotation for the first 90 does not suggest to me sudden TR drive failure.
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Old 9th Nov 2020, 21:40
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Originally Posted by noooby View Post
Golly, you guys must be subject matter experts on the 109 Series TR Control system to be so sure of what happened.
Having carried out a ‘Check A’ on the 109 every working day for the last decade and a half and having over 3,000 hours on type, I do have some idea of how the thing is put together.

One other “gotcha” on this type is that out of the two hydraulic systems, only #1 boosts the yaw servo. If #1 hydraulics drop off line, servo assistance is lost and the pedal feedback forces can be very high. It’s then very difficult to apply enough “boot” to keep the aircraft straight at low speed. The normal way to land in that condition is a running landing at about 30 kts, ideally with a crosswind from the left.
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Old 10th Nov 2020, 04:05
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Originally Posted by ShyTorque View Post
Having carried out a ‘Check A’ on the 109 every working day for the last decade and a half and having over 3,000 hours on type, I do have some idea of how the thing is put together.

One other “gotcha” on this type is that out of the two hydraulic systems, only #1 boosts the yaw servo. If #1 hydraulics drop off line, servo assistance is lost and the pedal feedback forces can be very high. It’s then very difficult to apply enough “boot” to keep the aircraft straight at low speed. The normal way to land in that condition is a running landing at about 30 kts, ideally with a crosswind from the left.
Going by the strange (oil) mess on the helideck, this makes the most sense.
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