dynamic rollover

dynamic rollover

If a helicopter lands on a sloped ground, there is a likelihood of its rolling over. In such a situation, a moment is produced by the horizontal component of total rotor thrust about the point of ground contact of the skid. This moment is opposed by weight of the helicopter. If the angle of bank of the helicopter, i.e., slope of the ground, is beyond a certain figure the restoring moment is too small to stop the helicopter from rolling over.A tendency of helicopters to begin rolling when they exceed the critical angle. Dynamic rollover is possible when a skid is caught by a projection on the surface or when landing on a slope. A helicopter is normally permitted to land on a 15° slope, but if the cyclic goes to full travel before all skids touch the surface, it should not be landed. Rollover occurs quickly because of the rapid decrease in the restoring moment. This same phenomenon occurs with floatplanes executing high-speed step turns in which the angular rotation becomes too high.