What happened
A Hughes 269B helicopter ditched in the ocean following an in-flight loss of control. During the event, the aircraft was in cruise flight at approximately 100 feet above the water. The pilot descended to an altitude of about 20 feet and decelerated to a speed of approximately 20 miles per hour.
At this altitude, the helicopter began to vibrate and the main rotor RPM started to decrease. In an attempt to recover, the pilot executed a right turn and increased the throttle. Although the pilot observed that the manifold pressure increased in proportion to the throttle application, the rotor RPM continued to decline. The pilot lowered the collective to try and regain the necessary RPM; however, because of the low altitude, the helicopter descended into the water. The pilot was not injured.
At the time of the accident, weather conditions at a local airport 1.5 miles from the site included winds from 110 degrees at 12 knots, with gusts up to 29 knots. The pilot reported that a tailwind was present when the loss of main rotor RPM occurred. The pilot had a total of 75 helicopter flight hours, including 40 hours in this specific make and model and 30 hours as pilot in command.