On June 26, 2002, about 0900 Alaska daylight time, a Robinson R-44 helicopter, N144AK, sustained substantial damage during an approach to a beach for landing, about 12 miles south of Shageluk, Alaska. The helicopter was being operated by Quicksilver Air Inc., of Fairbanks, Alaska, as a visual flight rules (VFR) positioning flight under Title 14, CFR Part 91, at the time of the accident. The solo commercial pilot was not injured. Visual meteorological conditions prevailed, and company VFR flight following procedures were in effect. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on June 27, the Federal Aviation Administration (FAA) inspector who interviewed the pilot, said the pilot told him he had been ferrying surveyors and survey equipment, and was returning to pickup surveyors when the accident occurred. The pilot said he was about 200 feet above the lake, making an approach to a beach, when he looked inside the helicopter to check the carburetor heat. The pilot said when he looked up he was headed, nose down, toward the surface of the lake. He leveled the helicopter above the surface of the lake, but during the attitude recovery, the tail rotor struck the water. The helicopter then settled into the lake, and sank in about nine feet of water. During a telephone conversation with the IIC on June 28, the director of maintenance for the operator said the helicopter had been recovered from the lake. He said a preliminary examination of the helicopter revealed some fuselage damage, and the drive-shaft flex coupling to the tail rotor gearbox was sheered. He said the bulkhead adjacent to the flex coupling was also damaged.