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Offshore deck landings “the leans”

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Offshore deck landings “the leans”

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Old 31st Oct 2017, 11:57
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Offshore deck landings “the leans”

Anyone up to explaining the cause and corrective action of an offshore landing on a stable deck when the aircrafts oleo are unequally compressed, causing the helicopter to “lean” to a side causing either left/right wing low?
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Old 31st Oct 2017, 14:40
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Can you repeat the quesion ?
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Old 31st Oct 2017, 15:24
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Cause: defective main oleo(s).
Corrective action: Change it/them.
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Old 31st Oct 2017, 16:28
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Or too much lateral cyclic........

Or perhaps a strong crosswind with not enough lateral cyclic to compensate.....
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Old 31st Oct 2017, 16:59
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Fairly normal for å Puma. Press brake pedals. Release park brake. Release brake pedals SLOWLY so the helicopter straightens up. Pull parkbrake on again - Done
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Old 31st Oct 2017, 17:28
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How about a rolling and pitching deck with a helicopter using fixed float bags?
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Old 31st Oct 2017, 19:25
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Raise collective to get "light" Lower collective smoothly (because we always do things smoothly) but firmly to "plant' yourself on the deck usually works. If that does not work you may have an oleo problem.
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Old 31st Oct 2017, 19:59
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Tailstinger has the right answer with a Puma. Touching down with a slight rearwards moment may cause one wheel to stick and hold up the oleo whilst the other slides and lets the oleo compress.

Landing on and pitching the aircraft slightly forward will let both oleos compress together.
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Old 31st Oct 2017, 20:08
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Depending on type, you can add tail rotor pedal to raise or lower a strut slightly. Especially types with high tail rotors. Best option is to add collective, use cyclic to center the attitude, then return to flat pitch and try to control the attitude as you lower the weight onto the struts. I personally use a combination of pedal and cyclic, typically it's because I didn't take enough pedal out lowering the collective, haha. High tail rotor thrust then rolls into the right strut, compressing it more.
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Old 31st Oct 2017, 20:24
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So in summary, if the oleos are serviceable it just comes down to poor landing technique................
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Old 31st Oct 2017, 21:05
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Being a world authority on heavy landings I never had a problem.
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Old 1st Nov 2017, 00:17
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Originally Posted by [email protected]
So in summary, if the oleos are serviceable it just comes down to poor landing technique................
^^This^^

Usually caused by slight forward motion on landing, with the brakes on. The oleo(s) compensate for the forward movement by compressing.

Fixed by Tailstinger’s method above. Apply pressure to pedal brakes, turn off hand brake, release pressure on pedals momentarily then reapply hand brake.

How to avoid it? Land vertically.
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