Summary
On 27 September 2012 at 15:00 UTC, a Bell Long Ranger helicopter, registration V5-HTZ, operated by Namibia Helicopter Services, experienced an engine failure while on an aerial work flight from Henties Bay to Walvis Bay, Namibia. The helicopter landed safely following an autorotation, but the main rotor struck the tail boom, severing the rear section. There were no injuries to the pilot or two passengers.
Flight History
The helicopter departed Henties Bay after completing aerial film work with one pilot and two passengers on board. Approximately two miles south of Swakopmund, the right booster warning light illuminated. The pilot checked the fuel pressure, which was sufficient, and the fuel gauge indicated over 300 pounds (166.6 liters) of fuel. The pilot continued toward Walvis Bay. At 11 miles inbound to Walvis Bay Airport, the pilot descended from 1000 feet AGL to 500 feet AGL and attempted to contact Walvis Bay tower, but received no response. The aircraft encountered light turbulence, and the engine began surging. After three surges, the engine shutdown and the engine-out warning light activated. The pilot immediately lowered the collective control stick to enter autorotation, maintaining a main rotor RPM and a speed of approximately 60 knots. The helicopter landed safely on the ground; however, during landing, the main rotor blades struck the tail boom, cutting off the rear section completely.
Aircraft and Pilot Information
The aircraft was a Bell Long Ranger, manufactured in 1985, with Namibian registration V5-HTZ. The last annual inspection was certified on 12 April 2012 at 9595.3 airframe hours. At the time of the accident, the aircraft had accumulated an additional 95 airframe hours. The pilot held a Commercial Pilot License (Helicopter) and was 49 years old with 8402.8 total flying hours, including 423 hours on type. The pilot's medical certificate was valid with no restrictions.
Investigation and Probable Cause
The accident was investigated by the Directorate of Aircraft Accident Investigation in the Ministry of Works and Transport. The probable cause was determined to be engine failure, with a contributing factor of fuel contamination. No safety recommendations were included in the final report.