I have encountered a strange problem when our small rotorcraft (2 meters rotor diameter, rotates clockwise when looking from the top) is hovering while an oncoming wind (about 10 knots) is blowing onto the platform. The craft begins to roll counterclockwise (if looking at the craft from the tail end forward and the nose of the rotorcraft to the wind.), loses altitude and if we don't take the controls and intervene rapidly, the craft could be lost. It rolls always in the same direction relatively to the wind. It means if we rotate the helicopter 90 deg, lets say right side to the wind, now it will pitch to the nose (again counterclockwise to the wind). At first we had twisted blades, which we thought might be causing the problem. However, after replacement with an untwisted blades, we still have the same problem. By the way, if there is no wind, then there is no problem. The helicopter has Bell-Hiller stabilization flybar with the pedals. Thank you.
Red Flag Submitted
Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action.
Reply To This Thread
Posting in the Eng-Tips forums is a member-only feature.