NTSB Identification: ERA10LA499
14 CFR Part 137: Agricultural
Accident occurred Friday, September 24, 2010 in Taylorsville, MS
Probable Cause Approval Date: 07/18/2011
Aircraft: BELL OH-58A, registration: N132HD
Injuries: 1 Serious.
NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
The helicopter pilot was surveying a field in preparation for aerial application. While he was maneuvering the helicopter about 100 feet above the ground, the engine lost all power without warning. The pilot noticed a space in between the trees and attempted to autorotate to that spot, but the helicopter impacted trees nearby. A postaccident examination of the wreckage revealed 16 gallons of fuel remained in the helicopter and no fuel contamination was observed. A successful test-run of the engine was subsequently performed. Examination of the fuel boost pump revealed that the inlet shut-off valve arm was bent, which could restrict fuel flow. When power was applied to the pump, it pumped fuel from a bucket; however, it did not appear to pump the fuel at maximum capacity. Further testing was performed utilizing both the bent arm and a replacement stock arm. The test results were similar for both arms, which were both below the pump's flow requirements. The bent arm was re-installed and a third examination was conducted at the pump manufacturer's facility, which revealed that the pump's ring tong terminals and pump cartridge were the incorrect models for the fuel boost pump; however, during the third test, the pump passed flow tests as received, and flow improved when the inlet valve stem assembly and cartridge were replaced. The bent inlet shut-off valve arm and/or incorrect fuel boost pump assembly could have resulted in a total loss of engine power; however, the investigation could not determine what, if any, effect they had on the helicopter at the time of the accident.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: A total loss of engine power while maneuvering at low altitude for undetermined reasons. Full narrative available
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