PPRuNe Forums - transmission examination after "hard landing"

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transmission examination after "hard landing"

I would appriciate if anyone can explain me what should be examined after a helicopter losses tail rotor effectivenes at 1000mAMSL, 20m AGL,turns right 720 deg and hits the ground on the skids, without any vissual damage.Helicopter was UH-1H, loaded with 10 passengers,3 crew and 1250 lbs of fuel on board at the time hard landing ocured.

Suggest your engineers read the Tech,book on heavy landings ,or try the Engineering Forum,or Rotorheads.You could offer a prayer to your God...

Nicely put Brian, Merry Christmas , best wishes for 2013 PH.

Instructor Pilot,

Is this the same unit and maybe the same IP that crashed an UH-1H during a botched training autorotation, and the same that had a tail boom/main rotor strike? And now a LTE with a hard landing?
Not to be judgemental but I think your organization needs some serious IP remedial training.
I know that the US Army doesn't provide that training anymore but there are several US federal government outfits that still operate the model that might be able to help.

I am not a maintenance expert but to answer your original question and based on your description of the mishap, I think that it warrants a hard landing inspection. In regard to the transmission examination, in my humble opinion if it didn't experience an overtorque or overspeed, I think that it's fine unless something else is found during the hard landing inspection. I did a quick search of the technical manuals (US Army TM 55-1520-210-23 series) and I didn't see anything specific about your problem.

You can PM if you wish.

As 'sycamore' suggests, go through the hard/heavy landing inspection requirements as detailed in the appropriate maintenance manual. Rather than 'examining the transmission' I would suggest you have a good close look at the transmission support structure, i.e. the 'hell-hole' exterior, and determine if structural distortion has occurred, run your hand slowly across the panels and ensure you feel a smooth flat surface - any waviness suggests distortion.