NTSB Factual Report

On June 22, 2018, about 1830 central daylight time, an amateur-built tricycle-geared Zenith Aircraft Company STOL CH-701 light-sport airplane, N736MM, sustained substantial damage during a forced landing after a loss of engine power in the traffic pattern at Maple Lake Municipal Airport (MGG), Maple Lake, Minnesota. The left seat private pilot and the right seat certificated flight instructor (CFI) sustained no injury. The airplane was registered to a private individual and was operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91 as a visual flight rules personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight originated from MGG about 1820.

In a conversation with the National Transportation Safety Board investigator-in-charge on June 26, the pilot reported that the purpose of the local area flight was to fly with his friend who was a CFI, to help increase his dual pilot flight instruction time. The pilot reported that upon taking off, he smelled a "burnt electrical" smell in the cockpit. The pilot and the CFI decided to remain in the traffic pattern due to the smell. While on the downwind leg for runway 10 (flying to the west), on the second traffic pattern iteration, the smell dissipated, and the engine began to backfire. During the backfiring sequence, the pilot observed the engine tachometer "jumping all over the gauge" from zero to a maximum indication. About 10 seconds after the backfiring began, the engine ceased producing power while about 700 feet above ground level and at an airspeed of about 50 miles per hour.

The pilot attempted to troubleshoot the backfiring and subsequent engine failure by switching fuel tanks and attempting a restart of the engine with no success. The pilot reported he decided to attempt a forced landing to runway 10. However, due to the presence of power lines that followed an east to west oriented asphalt-covered road on the north side of the airport (County Road 37), he assessed that he would be unable to fly over the power lines. The pilot attempted to execute a forced landing to the road. The airplane landed about 20 feet short of the road and impacted a ditch. The airplane came to rest in a grass-covered field about 400 feet to the northwest of the runway threshold for runway 10. During the forced landing sequence, the nosewheel collapsed resulting in substantial damage to the fuselage and the engine mount system. The right wing sustained substantial damage from impacting terrain.

The pilot reported that the airplane had an adequate amount of fuel for the flight and the airplane had no known previous issues with the airframe or engine that would have precluded normal operation.

The wreckage was recovered from the accident site to MGG for a future examination of the airplane. On June 26, a Federal Aviation Administration (FAA) aviation safety inspector from the FAA Minneapolis Flight Standards District Office traveled to MGG to examine the airplane.

The two-seat capacity, experimental category STOL (short takeoff and landing) airplane, serial number 7-8943, was built in 2016 by a private individual from a kit from the manufacturer. The airplane was powered by a 4-cylinder, 1.3-liter 115 horsepower Raven ReDrives 1300SVS fuel-injected automotive engine, originating from a Suzuki Geo Metro subcompact automobile. The propeller consisted of a ground-adjustable three blade composite assembly.