Accident Details
On July 24, 2009, at approximately 1829 eastern daylight time, a Robinson R44 II, registration N645JC, executed an autorotative landing into the Gulf of Mexico near Dunedin, Florida. The helicopter was owned by CFMC, Inc. and operated under 14 Code of Federal Regulations Part 91 as a personal local flight from Peter O Knight Airport (TPF), Tampa, Florida. Visual meteorological conditions prevailed; no flight plan was filed. The flight had originated from TPF about 1730.
Pilot Account
The pilot reported that earlier that day both fuel tanks were filled, and he flew an uneventful 15-minute flight. The helicopter was then hangared. Around 1730, he and two passengers returned for an intended local flight. After performing a preflight inspection and briefing passengers on life vests and entry doors, he started the engine and hover taxied for a midfield departure. He flew north 4 to 5 miles to remain clear of nearby Class B airspace, then northwest, west, and southwest towards Clearwater. He then proceeded over the Gulf of Mexico and turned right to fly north. While at 600 feet, after performing two 180-degree turns or a figure 8, the helicopter felt sluggish. No yaw motion or unusual vibrations were noticed, nor did he note the engine rpm. He applied forward cyclic to increase indicated airspeed and banked left. The low main rotor warning light illuminated; he banked right toward shore. The main rotor low warning horn then sounded, and he intended to descend into ground effect. Other lights, including the fuel light, came on. At 30 to 40 feet, he flared (applied aft cyclic) and pulled full collective up at or just before water contact. He then applied left cyclic to stop the main rotor blades. All occupants donned life vests (the passengers donned theirs) and swam to shore.
Post-Accident Examination
The helicopter remained submerged for over three days before recovery. A Federal Aviation Administration (FAA) airworthiness inspector examined the helicopter and engine. The four primary engine driven/rotor drive belts were in good condition and were cut for removal. The main fuel tanks were full of salt water; the auxiliary tank contained a mixture of salt water and about 6 inches of aviation fuel. The gascolator was also full of salt water. All fuel injection system components contained salt water. Hand rotation of the engine showed valve train continuity and compression on all cylinders. No defects were noted in the air induction or exhaust systems. The magnetos were rotated by hand and produced no spark at any ignition tower. Inspection of the servo fuel injector (fuel servo) revealed intact throttle and mixture controls; the fuel inlet screen had salt water contamination. The magnetos and fuel servo were retained for further examination.
Examination of the fuel servo at the manufacturer's facility with FAA oversight showed extensive external corrosion. After flushing with preservative oil, the unit was tested and did not flow to specifications. Disassembly revealed corrosion consistent with salt water submersion; no evidence of preimpact failure or malfunction was reported.
Examination of both magnetos at an FAA certified repair station with NTSB oversight found that the right magneto, tested as received, did not produce spark. After lightly sanding the corroded points, it produced spark at all ignition towers when operated between 643 and 4,704 magneto rpm. The carbon brush was stuck in the down position; no arcing on the coil tab or carbon tracking on the distributor block was noted. The capacitor measured 0.3 microfarads (specification 0.375 +/-10%). The left magneto, after similar sanding, produced spark at all towers between 643 and 4,704 rpm. Its carbon brush was also stuck down; capacitor measured 0.25 microfarads (specification 0.375 +/-10%).