On August 4, 1998, an Enstrom F-28F (registration N8619M) was involved in an aviation accident near Bryce Canyon, UT. Investigators recorded the probable cause as: The slight power loss appears to have been caused by the oil leakage pass[ing] the seals in the turbocharger. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter pilot experienced a drop in rotor rpm during eastbound departure. The engine produced no power, leading to a straight-ahead landing. After touchdown, the helicopter slid 30-40 feet, caught brush, and sustained landing gear and tail rotor damage, ending on its left side. An oil leak in the turbocharger was identified as the cause.
Incident Sequence
While departing to the east, the pilot noticed a drop in rotor rpm. The pilot rolled the throttle, but the engine did not produce power. The pilot then landed straight ahead, performing a high-altitude run-on landing. After touching down, the helicopter slid approximately 30 to 40 feet. During the slide, the left skid caught in ground brush, causing the left front support of the landing gear to break. The tail rotor blades became bent and, while still rotating, impacted the skid bar. The impact sheared the bar off and separated the gear box from the tail. The helicopter came to rest on its left side.
Examination Findings
An FAA inspector conducted a postaccident examination of the aircraft. The inspection revealed that the turbocharger had leaked oil into the induction system. According to the inspector's accident report, "The slight power loss appears to have been caused by the oil leakage pass[ing] the seals in the turbocharger."
Probable cause
The slight power loss appears to have been caused by the oil leakage pass[ing] the seals in the turbocharger.