Accident Overview
On September 8, 2019, at 1525 eastern daylight time, a Grumman G-164B, registration N8386K, was substantially damaged during an accident near Berlin, Maryland. The commercial pilot, who was the sole occupant, was not injured. The airplane was operating under Title 14 Code of Federal Regulations Part 137 as an aerial application flight.
Flight Details
The pilot reported that he was departing on the first flight of the day to conduct aerial seeding with 2,000 lbs. of wheat seeds. After liftoff, he noticed that the engine began to vibrate, but the rpm seemed normal. The pilot made a right turn, and the engine started to lose power and then "quit." The pilot stated that he was "too low to attempt a restart," and he performed a forced landing in a cornfield. During the landing, the airplane nosed over, and a post-crash fire ensued. The pilot exited the airplane and contacted the local authorities.
Wreckage Examination
Examination of the wreckage by a Federal Aviation Administration inspector revealed that the airplane's fuselage and both the upper and lower wings were buckled. The cockpit, firewall, and engine accessories showed fire damage.
Engine Examination
An examination of the engine revealed that the No. 9 pushrod was stuck in the open position and the gland seal was brittle. Borescope examination of the cylinders did not show any signs of scoring or internal damage. Valvetrain continuity was observed on the master rod, pistons, pushrods, and rockers while turning through 360°.
Maintenance History
A review of the engine logbook revealed that the No. 9 pushrod gland seal was replaced on the day of the accident before the accident flight. A test run was performed on the engine, and the airplane was returned to service.