From the RAF AH1 HT2/3 Gazelle Aircrew Manual:
In light wind conditions, an extremely rapid build-up of yaw rate can follow a relatively small left pedal application during low speed flight or in the hover, particularly with the SAS disengaged. In this event, immediate and positive application of right pedal, up to the maximum, should be applied and maintained to arrest the rate of yaw.
Recovery action may be ineffective if the pedals are returned only to the hover position, and the yaw rate may initially continue to increase before deceleration and an eventual steady hover is established.
Furthermore, if the pedals are not returned as far as the original hover position, a steady hover will never be achieved and the aircraft will stabilise at a particular rate of yaw which may be very high. Pilots may misinterpret this as a loss of yaw control. Be warned that any delay in applying corrective action will require progressively larger right pedal inputs to achieve a steady state hover and may lead the pilot to believe that he has lost control.
Yaw rates up to 165° per second to the left can rapidly be arrested by applying full right pedal without any discernable loss of fenestron performance.
In the hover and at low forward speeds, ensure that pedal turns to the left are always made slowly and smoothly.