Aircraft Accident Investigation Report

32 The magneto was secure in its mount at time of examination, the magneto hold down nuts were tight at the time of removal. Heavy fire damage as seen in Figure 32 precluded timing of the magneto due to internal damage and fire consumed parts. The magneto could not rotate at the time of examination. Figure 32 Engine Magneto The spark plugs were secure at each position. The spark plugs were removed, examined and photographed as seen in Figure 33. The spark plug electrodes remained mechanically undamaged, and according to the Champion Spark Plugs “Check-A-Plug” chart AV-27, the spark plug electrodes displayed coloration consistent with normal operation. The static oil soaking of the spark plugs (as noted) could be attributed to the engine positioning at mishap site and post recovery. Light corrosion was observed, this was likely due to post impact fire and heat. Figure 33 Engine Spark Plugs