On May 27, 2007, at 2046 eastern daylight time, N911GB, a Messerschmitt BO-105 helicopter, operated by Aviane Air Ambulance, was substantially damaged during a forced landing after takeoff from Vieques Hospital Heliport, Isla de Vieques, Puerto Rico. The certificated commercial pilot, two paramedics, a passenger, and the patient were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the air ambulance flight conducted under 14 Code of Federal Regulations Part 135. According to a Federal Aviation Administration (FAA) inspector, shortly after takeoff the helicopter's right engine lost power, so the pilot performed an autorotation to the ground. During the autorotation, the helicopter "landed hard," and was substantially damaged. Examination of the helicopter's right engine revealed the trim actuator control rod was disconnected, and the locking nut and washer, which secured the governor, were loose. According to maintenance records provided by the operator, the right engine was installed on the helicopter on May 25, 2007. The governors were also rigged during the installation. The helicopter flew approximately 3 hours since the maintenance was performed.