On September 1, 2018, about 1715 central daylight time, a Diamond Aircraft DA 40, N388MA, operated by the private pilot, was substantially damaged during a forced landing to a field, following a total loss of engine power during approach to Maury County Airport (MRC), Mount Pleasant, Tennessee. The private pilot incurred minor injuries. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight that departed MRC about 1615.The pilot reported that after flying over the local area for approximately 40 minutes, he returned to MRC and entered the airport traffic pattern for landing on runway 6. While on a downwind leg of the airport traffic pattern, he reduced the engine power in preparation for landing; however, the engine lost all power. The pilot then advanced the throttle in unsuccessful attempt to regain power. He subsequently attempted an engine restart with no success and at that time realized that the airplane would not be able to glide to the runway. The pilot then performed a forced landing to a field about 1 mile prior to the runway 6 threshold.

Examination of the wreckage by a Federal Aviation Administration inspector revealed that during the landing, the nose landing gear and left main landing gear collapsed, and the empennage separated from the airframe. The inspector added that although there was some damage to the wings, though their respective fuel tank remained intact. He drained approximately 4 gallons of fuel from the left fuel tank and 10 to 11 gallons of fuel from the right fuel tank. The fuel was 100-low-lead aviation fuel and appeared bright, clear, and absent of any visible contamination. Additionally, the fuel selector was found positioned to the left fuel tank prior to being moved to the off position by rescue personnel.

The inspector further examined the wreckage following its recovery to a storage facility. He was able to rotate the engine's crankshaft by hand and confirm crankshaft, camshaft, and valve train continuity to the rear accessory section of the engine. The engine had sat for almost 10 months and thumb compression was not attained on three of the four cylinders; however, a borescope examination of the cylinders did not reveal any anomalies. The mechanical fuel pump and magnetos tested satisfactorily. Air was blown through the fuel lines and no blockages were observed. No anomalies were noted with the fuel servo and it contained residual fuel. Its filter was absent of debris and the oil filter was absent of metallic contamination.

The four-seat, low-wing, fixed tricycle-gear airplane, was manufactured in 2005. It was powered by a Lycoming IO-360-M1A, 180-horsepower engine, equipped with a constant-speed, two-blade Hartzell propeller. The airplane's most recent annual inspection was completed on January 9, 2018. At that time, the airframe and engine had accrued 1,346 hours since new. The airplane flew an additional 40 hours from the time of the most recent inspection, until the accident. Review of a make and model airplane flight manual revealed that the left and right fuel tank each held 20.6 gallons of fuel, with .5 gallon unusable in each tank. According to a representative from the aircraft manufacturer, fuel unporting is possible with 4 to 6 gallons remaining in a fuel tank; however, it's more probable if the airplane is in a bank greater than a 45° angle.