Incident Details
A pilot departed from Panama City-Bay County International Airport to survey a boat on Deer Point Lake, approximately 8 miles northeast of the airport. While flying at an altitude of about 50 feet and a forward airspeed of 35 to 40 mph, the pilot initiated a circling maneuver. During the upwind leg, he reduced engine RPM. As the helicopter turned downwind, the pilot pulled up on the collective, but the helicopter began sinking instead of climbing. The pilot observed the rotor RPM dropping below 85% on the engine instruments. He immediately pushed the collective down but was unable to recover the RPM.
With the helicopter descending, the pilot deployed the emergency floats at approximately 10 feet above the water. The helicopter struck the water "hard" in about 4 feet of water and rolled onto its right side because the right flotation bag was torn off upon impact.
Investigation Findings
An FAA inspector who responded to the accident examined the helicopter after recovery. The inspection revealed that a pneumatic tubing line had backed off the governor, causing the engine to go to minimum RPM. The governor had last been installed 500 hours before the accident and showed signs of a torque seal on the B-nut. The pneumatic line that backed off the fitting is located on the backside of the governor, making it difficult to see and check for proper torque during routine maintenance.
No further factors were identified in the investigation.