LAX96LA104

The pilot experienced two engine chip warning light illuminations while conducting local air tours. After the second warning light illumination, the operator instructed the pilot to ferry the helicopter to the company's maintenance base. The engine sustained a total loss of power while en route to the maintenance facility and the pilot executed an emergency landing. The helicopter sustained a hard landing. The engine examination disclosed that the nose case (No. 1) bearing failed and the engine sustained a catastrophic failure due to oil starvation.

On February 1, 1996, at 1240 hours Hawaiian standard time, a Bell 206BIII Helicopter, N90194, experienced a hard landing while executing an emergency autorotation near Kamuela, Hawaii. The pilot was conducting a visual flight rules positioning flight to Waimea-Kohala Airport, Kamuela, at the time of the accident. The helicopter, registered to and operated by Kenai Air Hawaii, Inc., Kailua Kona, Hawaii, sustained substantial damage. The certificated commercial pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. The flight originated at Hilo International Airport, Hilo, Hawaii, at 1205 hours.

The investigating FAA inspector reported the engine nose case (No. 1) bearing failed and the entire rotating group seized. He also said that the pilot reported that the helicopter experienced metal chip detector warning lights on two previous flights.

The pilot reported in the accident report that he had been assigned to fly a tour flight schedule on the accident date. He departed Keahole Airport, Kailua Kona, at 0800 and arrived at Hilo Airport at 0836 in another helicopter.

He departed Hilo Airport in the accident helicopter on a tour flight at 0910. When returning from the tour flight, about 0950, the engine chip light illuminated. After landing at Hilo Airport, a mechanic removed the upper engine chip plug. The plug contained a small "metal flaking/fuzz" particle. The chip light did not illuminate during a post maintenance engine run-up.

The pilot departed on another tour flight at 1040. The engine chip light again illuminated during the return flight, about 1125. The mechanic removed the upper engine chip plug and found that it again contained a small "metal flaking/fuzz" particle.

The company management decided that the helicopter should not be used for further tour flights and that it should be ferried to Keahole Airport, the company's principal maintenance facility.

Selected portions of the pilot's written statement follows:

I departed Hilo Airport at 1205 local northwest bound and passing Honokaa I turned toward Waimea Airport climbing to 3,600 Ft. msl. Passing southeast of Lakeland, the ENG Chip light illuminated. [The] engine oil pressure began to fluctuate between 50 - 100 psi while the engine oil temperature remained constant at 95C [95 degrees Celsius]. [The] engine torque pressure began to fluctuate with the engine oil pressure. Two (2) minutes later the TOT [Total Oil Temperature] rose to 750 degrees at 70 percent torque. I then felt a slight shudder and brief vibration [which was] later determined probably caused by a windshear line (normal in this area). [The] TOT [gauge] then went to 800 degrees at minimum torque. I was approximately 1 1/2 miles east of the Waimea runway and turned directly toward the runway. After the turn I smelled what seemed to be hot oil, followed by initial [main] rotor decay. I entered autorotation at 3,000 Ft. msl indicated. After entry the LOW ROTOR RPM warning horn, followed by the ENGINE OUT warning horn, sounded. I maintained my autorotative descent and flared at 50 Ft. agl [above ground level] and applied full collective. [The] rotor RPM had deteriorated to 50 percent to full application, not much cushioning, resulting in a hard autorotative landing at 1240 local 1/2 mile southeast of midfield at Waimea Airport.

The engine was sent to Allison for examination. The disassembly examination revealed the engine sustained a catastrophic failure due to oil starvation. According to an Allison representative, the oil starvation resulted from the failure of the nose case bearing.