No fatalities

21 Jun 2015: GRUMMAN ACFT ENG COR-SCHWEIZER G 164A (N8598H) — KENNYS CROP DUSTING INC — Five Points, CA

Five Points, CA, United States

On 21 Jun 2015, a GRUMMAN ACFT ENG COR-SCHWEIZER G 164A (registration N8598H) operated by KENNYS CROP DUSTING INC was involved in an aviation accident near Five Points, CA. No fatalities were reported. Investigators recorded the probable cause as: Maintenance personnel’s improper reassembly of the engine during overhaul, which led to the failure of the supercharger-blower due to a lack of lubrication and the subsequent total loss of engine power during takeoff. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 1778583330Data APIEditorial standards

On June 21, 2015, a Grumman G 164A (N8598H) sustained substantial damage after losing engine power during takeoff near Fresno, California, resulting in a forced landing. The pilot was not injured. Examination revealed the engine's blower failed due to lack of lubrication.

Accident Summary

On June 21, 2015, at approximately 0600 Pacific daylight time, a Grumman Aircraft ENG COR-Schweizer G 164A, registration N8598H, was substantially damaged during an emergency landing near Fresno, California. The aircraft was owned and operated by Kenny's Crop Dusting, Inc., under 14 Code of Federal Regulations Part 137 for aerial application. The pilot, the sole occupant, was uninjured. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight, which was departing a private airstrip.

According to the pilot, shortly after takeoff, at about 50 feet above ground level, the engine lost power. The pilot executed a forced landing to a field, where the aircraft impacted the ground and came to rest inverted.

Engine Examination

On August 5, 2015, the engine was examined at Tulsa Aircraft Engines in Tulsa, Oklahoma. A complete report is part of the public docket. The starter drive gear was locked and unable to rotate by hand within the blower assembly, and it exhibited heat bluing. The starter shaft circumference matched the dimensions of the starter shaft bushing, resulting in zero side clearance or tolerance. The Pratt & Whitney R-1340 engine table of limits specifies a minimum required side clearance of 0.002 inches between the starter shaft and bushing. Examination revealed that the engine's blower failed due to a lack of lubrication to the impeller shaft and bearings.

Maintenance History

At the time of the accident, the engine had accumulated 2.0 hours since its last major overhaul. Maintenance records show the last major overhaul occurred on February 21, 2013, at a total aircraft time of 3,952.76 hours. The engine was installed on the aircraft on June 4, 2015.

Contributing factors

Recip eng supercharger — FailureMaintenance personnel