NTSB Narrative Summary Released at Completion of Accident
On March 28, 2000, about 1120 local (eastern standard) time, Peruvian National Police UH-1H, PNP-330, Bell Helicopter serial no. 68-16615, sustained substantial damage as the result of a hard landing following an autorotation to a rice field, approximately 13 nautical miles north of Tingo Maria, Peru. The copilot was at the controls of PNP-330, the second aircraft in a flight of three. In cruise flight, approximately 1500 feet above ground level, the flightcrew noted a sudden loss of power and reduction of engine noise. The aircraft commander took control and began an autorotative descent. Crewmembers and passengers observed the master caution light illuminate, as well as RPM and fuel pump lights. The crew instructed the passengers to brace for a hard landing. The helicopter landed hard and rolled on its left side. All three crewmembers and seven passengers exited the helicopter and assembled forward of the nose, with no injuries. There was a slight smell of fuel noted in the wreckage and no fire. The flight was conducted in visual meteorological conditions under the regulations of the Civil Aviation Authority, Peru.
An international investigation team began wreckage examination on March 30, 2000. They used fuel system examination guidelines obtained by international telecom with the Director of Product Safety, Allied Signal engines. Examination found a slight amount of fuel at the fuel control and complete fuel presence at the main fuel filter / housing. Examination of the approximately 2-feet-in-length section of fuel line and fittings between the main fuel filter and fuel control found the quick disconnect assembly partially separated and small pins in the quick disconnect were sheared. The shut-off feature / valve in the quick disconnect was in the home or fuel shut-off position.
The wreckage was removed from the site by means of external and internal lift by a PNP helicopter, for further examination at a PNP maintenance facility, Tingo Maria Airport. Both halves of the separated quick disconnect, sheared pins, and approximately 2-foot section of fuel line and other fittings were transported to the Materials Laboratory, National Transportation Safety Board, Washington, D.C., for a laboratory examination and a report to the Investigator-in-Charge.
Post-accident interviews of unit maintenance personnel revealed that a blue-colored fitting on the fuel line, located near the quick disconnect, had been disconnected and reconnected in maintenance action the day prior to the accident. The blue fitting was part of the subject approximately 2-foot section of fuel line and fittings, and located approximately 3 inches inboard, towards the fuel control / engine, from the red-colored quick disconnect. The blue fitting was disconnected and later reconnected by supervisory maintenance personnel to defuel the helicopter following a maintenance write-up (in the subject write-up, March 26, the 20-minute low fuel light had illuminated in flight at a fuel quantity that was not within tolerances for light illumination). Unit maintenance personnel interviews further revealed that the blue fitting was the normal fuel system disconnect point in order to defuel this model helicopter.
For further information, contact:
Investigator-in-Charge Javier Gurmendi Comandante DIRAVPOL-PNP Lima, Peru tel. 4486987 8707711
U.S. Accredited Representative:
Thomas R. Conroy Senior Air Safety Investigator National Transportation Safety Board Office of Aviation Safety, Regional Operations and General Aviation Division, AS-20 490 L'Enfant Plaza East, S.W. Washington, D.C. 20594 tel. (202) 314-6314 / fax. -6329