What happened
Prior to takeoff, the pilot performed a pre-flight inspection and an engine run-up, reporting no unusual findings. During the takeoff roll, the pilot rotated at 80 mph. As the Cessna aircraft began its climb, the RPM of the left engine dropped to 1,500 RPM, causing the airplane to veer to the left. The pilot was unable to maintain altitude or directional control, and the aircraft struck the ground with the left wing followed by the nose. A witness reported hearing a loud popping noise when the aircraft was approximately 15 to 20 feet above the ground; the witness noted that while the engines briefly revved up, the aircraft continued to climb with engine revs that were louder than normal.
The investigation
The engines were examined under the supervision of a Federal Aviation Administration (FAA) inspector, and no mechanical deficiencies were initially noted. The aircraft was subsequently released to its owner. However, during a later teardown of the left engine by a salvage company, it was discovered that the main bearing was partially seated on the journal and exhibited a blue discoloration.