Accident Overview
The pilot was conducting a local VFR maintenance test flight, departing from an airport situated in a highly congested area with a tree line at the end of the runway. The airplane had just been restored, and this was its first flight in 19 years.
Witness Observations
Witnesses reported that shortly after lift-off, the airplane's engine began to backfire and then quit. The airplane then entered a right bank, stalled, and crashed into a residence's backyard.
Investigation Findings
The investigation revealed that both magneto hold-down nuts were loose, and the engine timing could not be determined. The left magneto would only produce a spark in one lead, and the right magneto would not fire when their respective drives were hand rotated. However, the magnetos operated normally when tested without the engine's ignition harness.