ERA09LA239

The student pilot was practicing stop-and-go landings on runway 36 under the supervision of his flight instructor. Shortly after the fourth takeoff, a reduction in engine power was observed with the throttle in the full open position. The instructor took control of the airplane and attempted a left hand turn to land on runway 18. The engine did not regain full power and a forced landing was made on airport property, short of runway 18. The airplane collided with a drainage ditch during the landing and was substantially damaged. Examination of the airframe and engine did not reveal any evidence of a pre-existing mechanical malfunction or failure. During a post-accident test run, the engine started normally and produced rated horsepower with no hesitation or interruption in power.

On April 11, 2009, about 1720 central daylight time, a Diamond DA 20-C1, N964CT, was substantially damaged following a forced landing at Bomar Field (SYI), Shelbyville, Tennessee. The airplane was registered to Wings of Eagles LLC and operated by Wings of Eagles School of Flight. The commercial-rated flight instructor and one student sustained serious injuries. Day, visual meteorological conditions prevailed at the time, and no flight plan was filed for the 14 Code of Federal Regulations Part 91 instructional flight. The flight originated at Smyrna Airport (MQY), Smyrna, Tennessee, at 1630. An inspector from the Federal Aviation Administration (FAA) reported that the flight instructor and his student were performing stop-and-go landings on runway 36 at SYI. After the fourth takeoff, at an altitude estimated to be about 300 to 500 feet above ground level (AGL), the engine lost power as if it were "throttled back." The instructor noted that the engine was operating at reduced power with the throttle in the full open position. The instructor took control of the airplane and initiated a left turn to attempt a landing on runway 18. The engine did not regain full power and a forced landing was made on airport property, short of runway 18. During the landing, the airplane collided with a drainage ditch and came to rest approximately 150 feet from the initial touchdown point. An initial examination of the wreckage revealed that the airplane came to rest in a grass field in a 10-degree nose down attitude. The nose gear was collapsed and the engine was still attached to the firewall; however, the engine mount was bent to the left approximately 20 degrees. The propeller blades were broken off at the blade roots and there were rotational scoring marks on the ground near the wreckage. The empennage was severed at its midpoint. Continuity was established from the cockpit to the engine and flight controls. The airframe fuel screen and the fuel lines were free of obstructions. A sample of fuel was taken from the aircraft and tested with water-finding paste; no evidence of water was found. The electric fuel pump operated normally in the low and high positions. The maintenance fuel cutoff valve was correctly safety wired and in the ON position. The engine was shipped to the Teledyne Continental Motors facility, Mobile, Alabama, for examination and an engine test run. An FAA inspector provided oversight. The engine exhibited impact damage concentrated on the lower section. Soil was impacted into the external surfaces of the engine. After the external examination, it was determined that a test run could be attempted. The following parts were replaced or repaired prior to the run: exhaust tubes, ignition system harness, number 2 cylinder induction tube (repaired with tape), oil sump, and number 2 cylinder rocker cover and gasket. The engine was prepared for the run by installing thermocouples, pressure lines, and test pads for monitoring purposes. The engine startednormally on the first attempt. The engine was operated for a period of 20 minutes at various throttle settings including full open. Throughout the test run, the engine accelerated normally without hesitation, stumbling, or interruption in power and demonstrated the ability to produce rated horsepower. The certificated flight instructor held a commercial pilot certificate with airplane single- and multi-engine engine land ratings. According to FAA records, the student did not possess any pilot ratings or a medical certificate. The 1656 weather observation for MQY, located 27 nautical miles north of the accident site, included the following: surface winds from 010 degrees at 6 knots, gusting to 15 knots, 10 statute miles visibility, scattered clouds at 4,700 feet, temperature 18 degrees Celsius (C), dew point 6 degrees C, and an altimeter setting of 30.15 inches of mercury.