Mart,
The XH-59A ABC uses differential collective for yaw control during slow-speed powered flight. Above 80 kts the differential has been phased out and the rudders have taken over.
The vertical tails is swept back and the rudders are not effective enough during autorotation. They proposed inverting the vertical tails.
These inverted tails can be seen on the proposed X2 configurations. [US design patents ~ D524,227, D524,228, D524,229, D524,230, D524,718 and D526,269]
Nick,
I take back the years of saying bad things about the tail-rotor.
Long live the tail-rotor
. Or the nose-rotor, or both.
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A Teaser
Anyone want to guess how the transition from hover to cruise is done?
