On September 18, 2016, at 2006 central daylight time, a Cessna 172S, N52265, impacted terrain during a go-around from runway 26R at Spirit of St Louis Airport (SUS), Chesterfield, Missouri. The airplane descended after it entered into a right nose-down turn while turning downwind for runway 26R. The airplane was destroyed. The commercial pilot sustained serious injuries. The rental airplane was registered to Christiansen Aviation Inc and operated by Air Associates of Missouri under 14 Code of Federal Regulations Part 91 as a personal flight that was not operating on a flight plan. Night visual meteorological conditions prevailed at the time of the accident for the flight that originated from SUS. A flight instructor at SUS stated that during the right downwind leg for runway 26R, the airplane's altitude was "erratic as it pitched up and down" with "large power adjustments." The airplane's approach seemed "very unstable." As the airplane approached the runway, it entered a go-around. He stated that the go-around was "just as unstable." The airplane had overshot the runway and was well left of the runway centerline during the climb out from the go-around. The flight instructor then ran into the flight school building where he worked in attempt to assist the pilot by radio. As he reached for the radio, he heard the airplane engine accelerate and then heard a "loud thud." He ran out onto the ramp and did not hear any additional sounds. He concluded that the airplane impacted terrain. The Federal Aviation Administration (FAA) Coordinator for the accident stated that the pilot was "coming in fast" on an approach to landing. The pilot then performed a go-around from runway 26R. When the pilot turned the airplane onto a right crosswind leg, he lost airplane control. The airplane impacted the ground about 150-200 yards northwest of runway 26R. There were no mechanical anomalies that would have precluded normal airplane operation. A requested written statement of accident investigation findings from the FAA Coordinator was not received. FAA provided photos showed that the airplane resting in an inverted orientation at the end of the ground scar and the right wing was separated at the wing root. The right wing was resting along the ground scar, and the left wing was attached to the airframe. The left wing flap was in the retracted position. The cockpit throttle control was out about ½ inch and the mixture control was in the full forward position. The cockpit fuel selector had both wing fuel tanks selected. The cockpit pitch trim indication was in the full nose-down position. The cockpit wing flap selector was in the 0-degree flap position. The standby altimeter indicated about 425 feet mean sea level and the altimeter was set to about 29.96 inches of mercury. The Hobbs meter indicated 2,729.9 hours. The tachometer indication was not reported and is unknown. It is unknown if the Hobbs meter sustained impact damage rendering it unreliable. Maintenance records recorded tachometer times and not Hobbs time. The last 100-hour inspections for the airframe and engine were at a tachometer time of 2,067.6 hours. A National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report (form 6120) was not received from the pilot.