CEN17LA313

The sport pilot was conducting a cross-country flight when the experimental amateur-built airplane experienced a loss of engine power; the pilot then conducted a forced landing to a field, and the airplane sustained substantial damage. Postaccident examination of the airplane revealed a broken wire to the airplane's alternator; this specific wire supplied electrical power to the alternator field coil. Because the wire was broken, the alternator was rendered inoperative. The pilot would not have been able to detect the broken alternator wire without removing the engine cowl, which is not normally part of a pilot's preflight examination. The airplane's engine had been modified to use an ignition system that operated from the airplane's electrical system, which included a battery and the alternator to maintain the battery's charge. Once the alternator field wire had broken, the ignition system relied completely on the airplane battery's reserve power as the source of ignition power. Once the battery power was depleted, the ignition system could not operate, and the engine lost power due to the lack of ignition.

On July 20, 2017, about 1645 central daylight time, an amateur-built Canion, Zodiac 601XL airplane, N577M, received substantial damage to the engine firewall during a forced landing to a field following a loss of engine power near Grady, Arkansas. The pilot was not injured. The aircraft was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was not on a flight plan. The flight originated from the Center Texas Municipal Airport (F17) about 1330 and the intended destination was the Kirk Field Airport (PGR), near Paragould, Arkansas. The pilot reported that about 90 minutes into the flight he lost power to his on-board avionics equipment. Shortly thereafter, the airplane's engine lost all power and the propeller began windmilling. Attempts to restart the engine were unsuccessful and the pilot attempted an off-airfield landing to a corn field. During the landing the nose wheel "dug in". Examination of the airplane after the accident revealed a broken wire to the airplane's alternator. Specifically, the broken wire supplied electrical power to the alternator field coil, rendering the alternator inoperative. Additionally, the airplane's engine had been modified to use an electronic ignition system that operated from the airplane's electrical system. The electrical system included a battery and the alternator to maintain the battery's charge. The airplane received damage to the firewall and forward fuselage supporting structure.