Accident Details
During a water-taxiing maneuver, a helicopter equipped with fixed floats experienced a dynamic rollover. The pilot reported that while moving in a right sideways direction, the helicopter rolled to the right, struck the water, inverted, and submerged. The pilot, the sole occupant, was able to exit the inverted cockpit, inflate his life vest, and swim to shore.
Damage
The accident resulted in substantial damage to the main rotor system, tail rotor, and fuselage.
Mechanical Condition
The pilot reported no preimpact mechanical anomalies with the helicopter.
Dynamic Rollover
The helicopter's tendency to continue rolling when the critical angle is exceeded—as when one skid is caught on the surface and the helicopter pivots around that point—is characteristic of dynamic rollover.