On May 10, 2008, at 1215 central daylight time, a Robinson R22 Mariner, N8316D, a single-engine helicopter, sustained substantial damage when it collided with the water while maneuvering over Lake Travis, in Austin, Texas. The certified commercial pilot and the pilot rated passenger were not injured. The helicopter was registered to a private company and operated by Boat Pix, West Palm Beach, Florida. No flight plan was filed for the flight that departed Austin-Bergstrom International Airport (AUS), Austin, Texas, around 1030, and was destined for Lake Travis. Visual meteorological conditions prevailed for the business flight conducted under 14 Code of Federal Regulations Part 91. Several witnesses observed the helicopter flying at a low altitude over the boats on Lake Travis. One witness said, "The Boatpix helicopter was flying around another boat and then headed our way. He traveled directly over our boat and veered to the starboard. He was about 50 feet off the water - when he passed he rose up then circled behind us. When he passed the boat his angle of attack was pretty steep. He took a hard right bank turn - came down low and back at us - following from our stern - came down to the water and bounced the pontoons onto the water. It started to dig in the water and I turned to shield myself." The next time the witness saw the helicopter it was upside down in the water. Another witness was driving a ski boat when he first noticed the helicopter performing what he described as "aeronautic maneuvers." He said, "These [maneuvers] appeared to be dangerous because they were 6-8 feet off the water, then they would pull up sharply and bank right." The witness then observed the helicopter fly directly over him followed shortly after by the sound of a "slapping" noise. He then saw the helicopter's two pontoons floating in the water. In a written statement, the pilot stated that he and the pilot rated passenger were tracking a boat approximately 100 feet above the ground level. The boat was traveling to the south and they were flying to the north with a tail wind. He said, "I executed a right hand turn and noticed that the rotor RPM had begun to decrease, the rotor RPM horn came on, and my governor light began to flash. I immediately began to execute a low rotor RPM recovery by lowering the collective, rolling on more throttle, and continuing to turn into the wind. I tired to recover the RPM but noticed we would not recover RPM before hitting the water." The pilot told the pilot rated passenger that they were not going to recover and he attempted to use the remaining rotor RPM to slow the descent. The helicopter hit the water and bounced back up with a bit of a wave. When the helicopter came back down, a wake from one of the boats they had been tracking washed over the floats, which caused the helicopter to roll to the front and flip over. The pilot rated passenger provided a similar account of the accident sequence in a separate written statement. The helicopter was towed to the shore and recovered. The governor controller (part number: B286-2, serial number 1415) was removed and sent to Robinson Helicopter Company where it was examined under the supervision of the Safety Board on May 21, 2008. When examined, there was no visible external damage to the unit. It was installed on a calibrated test bench and subjected to the acceptance test protocol in Robinson Helicopter Company Process Specification RPS-59. The controller assembly met all acceptance criteria for a new or factory overhauled until, which applies to a controller returned from the field. The controller was not unsealed for a visual inspection of the internal components because it met the above acceptance criteria. The pilot held a commercial pilot certificate and certified flight instructor rating for helicopters. His last second class FAA medical was issued on March 10, 2008. He reported a total of 895.4 hours, of which 871 hours were in the same make and model as the accident helicopter. Weather at Austin-Bergstrom International Airport, about 23 miles west of Lake Travis, at 1153, was reported as wind from 190 degrees at 12 knots gusting 17 knots, visibility two miles and haze, clouds broken at 1,800 feet, overcast clouds at 2,200 feet, temperature 79 degrees Fahrenheit, dew point 41 degrees Fahrenheit, and a barometric pressure setting of 29.75 inches of Mercury.