Bell 206B N167H

The 1,936-hr commercial pilot departed at 0705 with three passengers for an oil platform, in the Gulf of Mexico. Prior to departure, the helicopter was serviced with 50 gallons of fuel (approximately 1 hour and 50 minutes flying time with no reserve). The pilot reported, "landing" on the first platform at 0829. After landing, oil was observed on the side of the fuselage and the pilot could not see any indication of the transmission oil level. A mechanic determined that the transmission had been over-serviced and residual oil had caused the oil streaking on the side of the helicopter. The accident pilot informed the mechanic that he didn't have fuel for a 30+ minute ground run. The mechanic informed the accident pilot that they could do about a 5-minute run and then do about a 5-minute hover after the engine cowlings were in place. The pilot who brought out the mechanic, offered to get fuel for them; however, the accident pilot declined the offer, stating that he, "could do this without any problems". The second helicopter departed at 1313, leaving the accident pilot and mechanic to complete their engine run and flight over to a second oil platform for refueling. The accident pilot reported his departure at 1359 and then reported "landing" at 1410. As the helicopter approached the oil platform from the south and made "some strange turns left and right". Then it straightened up and headed to the heliport. Just before the helicopter got to the heliport, it "sounded like it lost power and started dropping rapidly." The helicopter descended below the platform's living quarters and witnesses heard the helicopter contact the oil platform and fall into the water below. The emergency floats did not deploy. A visual inspection of the powerplant was accomplished; no obvious abnormalities were noted. The fuel tank and bladder had been breached by the impact. Various fuel lines were checked, a small amount of ( approx. 1 teaspoon) water/fuel was found in the fuel line between the firewall check-valve and fuel nozzle. The fuel line between the fuel control and firewall check-valve was absent any fluid. The canister housing the fuel filter was removed and opened, the fluid quickly separated into about a 90/10 water and fuel mixture; a laboratory analysis later identified the fluid as saltwater and fuel. The fuel line between the fuel filter and airframe bulkhead contained about 3 tablespoons of fluid (mostly water). The engine was dissembled and inspected; both the compressor and turbine sections exhibited no abnormalities. The engine's accessories consisting of the fuel control, power turbine governor, fuel pump, and fuel nozzle were all "bench tested" at the operators maintenance facility. No discrepancies were found with the engine accessories, the engine's accessory gearbox, or the main rotor transmission. Drive and flight control continuity was established to both the main and tail rotor systems. An inspection of the cockpit cabin, found the pilots seat and shoulder belts fastened and the passenger's seat and shoulder belts unfastened. Additionally, the landing gear emergency float system was found in the unarmed position. The caution panel was removed and examined. Two bulbs contained filaments that were stretched and broken; the fuel pump and engine-out anunciators. The low-rotor anunciator light bulb contained filaments that were stretched, but not broken.

Quoted verbatim from the NTSB record.