On May 6, 2020, about 1650 central daylight time, a Cessna T240 airplane, N25HE, was substantially damaged during a runway excursion after landing at the Roger M. Dreyer Memorial Airport (T20), Gonzales, Texas. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot entered the airport traffic pattern for runway 33 and set the wing flaps to the takeoff (12°) position. The airspeed on final approach was about 130 kts and he extended the speed brakes to reduce the speed. He did not use full landing flaps (40°) because he was concerned about the "strong wind gusts." The airplane touched down approximately one-third of the way down the runway at about 100 kts. The pilot stated he did not believe the airplane would be able to stop on the remaining runway and decided to execute a go-around. He added full engine power and left the flaps at the takeoff (12°) position. He did not recall retracting the speed brakes and noted the airplane seemed to get "no lift." The airplane subsequently departed the runway pavement and came to rest about 200 yards beyond the end of the runway in a field. The pilot commented the go-around could have been initiated earlier. He stated there were no mechanical failures or malfunctions before the accident. Federal Aviation Administration inspectors conducted a postaccident examination of the airplane at the accident site. At the time of the examination, the cockpit speed brake switch was in the UP position. The speed brakes were in the down (retracted) position at that time consistent with the airplane electrical power being off. Recovery personnel confirmed damage to the right wing and engine mount. The airplane flight manual (AFM) noted the speed brakes can be used for glide path control on final approach and airspeed reduction. Both the normal and short field landing checklists specified, "SPD BRK Switch – UP (as desired)" after touching down. The balked landing (go-around) checklist included retracing the speed brakes, "SPD BRK Switch – DN." The amplified landing procedures contained in the AFM did not include any additional guidance related to the use of the speed brakes. According to the airframe manufacturer, the speed brakes are electrically actuated by the cockpit instrument panel mounted switch. They will not retract automatically due to a go-around condition, pressing the go-around button, or throttle lever advancement. The flight manual systems description stated there are three conditions that will automatically retract the speed brakes: if the circuit breaker is pulled, if they deploy asymmetrically, or due to a low voltage electrical condition.