Originally Posted by
The Sultan
The tail is a severe vibratory environment on any rotorcraft. More so on an ABC type with inherently brutal vibration levels. As all this is common knowledge, you would think Sikorsky would run the tail at no thrust while they expand their hover envelope if they could. Points to a serious drive system issue.
Perhaps they designed in a mitigation and are just testing it as they intend to fly. In any case, there’s probably some learning that will happen at the rear end of the aircraft. Hope they publish some papers!