On June 21, 1984, a Bell 47G-5A (registration N14807) was involved in an aviation accident near Houma, LA. Investigators recorded the probable cause as: The fracture of the fuel control governor spring (part number 2529242), which drove the fuel control to idle and caused a partial loss of power during pipeline patrol. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter suffered a partial power loss during low-altitude pipeline patrol due to a broken fuel control governor spring, leading to an autorotation into trees and marsh.
What happened
The helicopter was conducting a pipeline patrol at low altitude when it experienced a partial loss of power. Following the mechanical failure, the pilot initiated an autorotation. The aircraft ultimately impacted trees and marsh land during this emergency descent.
The investigation
Post-acc examination of the engine revealed that the fuel control governor spring, part number 2529242, had fractured. This breakage drove the fuel control system to idle, resulting in the loss of power that necessitated the autorotation.
Findings
The accident was caused by fuel exhaustion due to a mechanical failure of the fuel control governor spring. The helicopter was on a pipeline patrol at low altitude at the time of the power loss. Examination of the engine after the accident revealed that the fuel control governor spring, part number 2529242, had broken driving the fuel control to idle.
Probable cause
The fracture of the fuel control governor spring (part number 2529242), which drove the fuel control to idle and caused a partial loss of power during pipeline patrol.