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Old 3rd November 2018 | 13:21
  #68 (permalink)  
SASless
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From: Downeast
TC,

This is what I posted:

An example....had the crew landed immediately upon realizing they had lost tail rotor control and got the Throttles moved back to ground idle or shutoff....they might have avoided going swimming.
When you are that close to landing on a Deck (elevated helipad, roof top helipad....or anywhere for that matter) and you are unable to stop a yaw to the right (American design)....how long does it take to know you have a problem....45 degrees of yaw....90 degrees....180 degrees....360 degrees 720 degrees?

Yes there is a delay before you realize you have a problem.....yes....there is a delay while you process that recently learned knowledge.....then you have to formulate your plan....execute your plan....and then see if your plan is working.

My point in presenting the video was to demonstrate how quickly the situation gets out of hand.....if retarding the Engine Levers is delayed.....FOR WHATEVER REASON!

Boy Scout Motto is "Always Prepared!".....that works for Helicopter flying too.

From personal experience....when my left foot touched the chin bubble and the aircraft was still turning right.....even my slow thinking Red Neck Brain grasped there was a problem....instantly!

That same slow thinking brain worked better if it was like the old fashioned water well pump....the kind that had to be "primed".

That is where training and SOP's (Cockpit Procedures) come into play.

I do firmly believe....had the Handling Pilot firmly bottomed the Collective before the aircraft or as the aircraft rotated past the starboard side of the ship....they might possibly have stayed on the deck and had a better outcome.

(As we do not know for real at what point the ECL's were retarded....we can only guess they were still powered when the aircraft rolled over onto its side and spinning like a Top.)

As it was....they had one heck of story to tell in the Bar later....all survived and only one crew member was injured with a broken arm.

The teaching point is simple....at or near a hover and you lose Tail Rotor Drive/Thrust....holdiing the Collective up is not going to end well.....but landing the helicopter and getting the power off as quickly as possible is the far better course of action.

In the specific case of Helicopters with Collective mounted throttles....I would reverse that order.....meaning roll off the Throttle(s) then carry out an EOL.
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