On March 24, 2025 about 0804 eastern daylight time, a Cirrus Design Corporation SF50, N56GY, was substantially damaged when it was involved in an accident at Kissimmee Gateway Airport (ISM), Orlando, Florida. The commercial pilot was not injured. The airplane was operated as a Title 14?Code of Federal Regulations Part 91 executive/corporate flight.? The pilot stated that he performed a standard preflight, utilizing the Federal Aviation Administration (FAA) Approved Airplane Flight Manual external checklist with no discrepancies reported, but he did not check the fuel tanks for contamination, believing that task would be accomplished by Cirrus personnel. One Crew Alerting System (CAS) message associated with engine start volts low was noted before engine start, but the engine started normally, and the message extinguished after engine start. The flight departed from runway 24 about 0725, and after takeoff was flying with the autopilot and autothrottle engaged. According to data downloaded from the recoverable data module (RDM) along with pilot provided information, while climbing at flight level (FL) 198, about 0737:23 the message FADEC NO DISPATCH Caution displayed. He went thru that checklist while continuing to climb and reported the message continued following checklist completion, but continuance of the flight was allowed. About 2 minutes 19 seconds later while flying at FL234, the red FADEC CTRL DEGRADED Warning illuminated. He pulled up that checklist and worked through it but the message continued. He contacted the controller and requested a vector to return to ISM, but did not declare an emergency at that time. He reported performing the FADEC Reset via the multi-function (MFD) display and recalled a warning that the engine power may not be reliable. In going thru that checklist, the engine did not respond to thrust lever change, so he then declared an emergency with the controller. While descending he attempted to slow the airplane using the manual mode of the autothrottle by setting a target speed of 180 knots indicated airspeed (KIAS), but the airplane did not slow, nor did the thrust lever move as expected. At that time the flight was in close proximity to ISM while the thrust remained at + or – 30% so he requested delaying vectors as the flight was fast and close to ISM. He then pushed the thrust lever full forward and the thrust increased to 42%, then brough it back to flight idle and the thrust decreased to 1%, which did not change with further thrust lever advancement. The pilot added that having the thrust go from 30% to 1% added a new level of complexity to the situation. The pilot considered either deploying the Cirrus Airframe Parachute System (CAPS) or gliding to ISM and noted the later was possible. At that point while on the base leg of the airport traffic for runway 6 at ISM, he extended the flaps to 50% and proceeded to the runway lowering the landing gear and flaps to 100% at the last minute. The flight touched down fast 2/3’s down the 5,001 ft long runway and he was unable to stop using normal brakes. The flight rolled off the end of the runway onto grass and collided with an airport boundary fence. He shut down the engine, which occurred at 0804, and evacuated the airplane. A review of the maintenance records revealed that on March 18, 2025, when turning on power a “FADEC No Dispatch and FADEC CTRL Degraded” CAS Messages were displayed. A download of the FADEC was performed and the information was provided to the engine manufacturer. Because the airplane was on a list for replacement of the fuel control unit (FCU) by a Service Bulletin, the FCU was removed and a modified FCU was installed on March 20, 2025. Following the replacement of the FCU maintenance personnel performed acceleration and stability checks with no discrepancies noted. The maintenance was signed off on March 21, 2025, and the accident flight was the 1st flight since the modified FCU was installed. Following postaccident examination of the airframe and engine, the engine was removed and sent to the manufacturers facility for further examination and testing.