DFW06LA172

Shortly after departure, the airplane's engine lost partial power, and the 604-hour private pilot elected to perform an emergency landing to a road. While landing, the airplane's rotating beacon collided with an unmarked static transmission line and the left wing tip impacted a mailbox. An examination of the engine revealed that the right magneto had experienced an internal failure which resulted in its misfiring. The right magneto had been installed eight years previously and had accumulated approximately 469 hours since it was last rebuilt. A service bulletin previously issued by the magneto manufacturer stated, the "magneto must be overhauled or replaced at the expiration of five years since the date of original manufacture or last overhaul...without regard to accumulated operating hours."

On June 29, 2006, about 1209 central daylight time, a Piper PA-32-300 single-engine airplane, N70746, was substantially damaged during an emergency landing following a partial loss of engine power near Midland, Texas. The non-instrument rated private pilot and passenger were not injured. The airplane was registered to and operated by the pilot. Visual meteorological conditions prevailed and no flight plan was filed for the 14 Code of Federal Regulations Part 91 personal flight. The 392-nautical mile cross-country flight originated at 1151 from the Midland Airpark (MDD) near Midland, Texas, and was destined for the Baytown Airport (HPY) near Baytown, Texas.

According to the 604-hour private pilot, approximately 14 minutes after she departed MDD, the engine started to "sputter." The pilot reported that she turned on the boost pump and switched fuel tanks; however, the engine continued to "sputter." Since she was unable to maintain altitude, the pilot elected to perform an emergency landing to a road. Shortly before the airplane touched down, the rotating beacon, which was located on top of the vertical stabilizer, collided with an unmarked static transmission line. During the landing roll the left wing tip impacted a mailbox.

A representative from the Federal Aviation Administration responded to the accident site and reported that the airplane's rudder had sustained structural damage.

An examination of the engine revealed that the right magneto's distributor gear bushing had failed. A review of the engine logbook revealed that the right magneto, a Teledyne Continental Motors (TCM) / Bendix S6LN-1200, P/N 10-349310-1, S/N H279705FR, had been installed on October 24, 1997, and had accumulated approximately 469 hours since it was last rebuilt.

According to Teledyne Continental Motors (TCM) service bulletin SB643B, section 3, paragraph C, a S-1200 "magneto must be overhauled or replaced at the expiration of five years since the date of original manufacture or last overhaul...without regard to accumulated operating hours."