The airplane climbed to about 150 ft agl shortly after takeoff and then began a 180° turn back to the airport. After overflying the departure runway in the opposite direction, the airplane appeared to enter the left downwind traffic pattern to return for landing. As it turned from the downwind to base leg, it rolled left and into the ground. Both the pilot and passenger were fatally injured.Witness accounts, along with evidence in the wreckage, indicated that the landing gear was extended during the return leg and at the time of impact. Also, a witness recalled that he heard a radio transmission from a pilot stating that he was having landing gear trouble and was coming back to the airport.The pilot reported to his mechanic that on one prior occasion the landing gear had failed to retract completely, but he had resolved this by recycling its circuit breaker. The mechanic was not able to find anything wrong with the landing gear during inspection; however, it is likely that the pilot was returning to the airport after being unable to retract the landing gear.Although the temperature at the time of the accident was high, the airplane was not heavily loaded, and should still have had adequate power to continue the climb to pattern altitude to allow the pilot to troubleshoot whatever problem he may have encountered. The airplane maintained altitude, albeit low, during the return leg, so a total loss of engine power could be ruled out, although a partial loss of power was possible.Irrespective of the problems the pilot was encountering, he had successfully maneuvered the airplane back to the airport and had the opportunity to land on the opposite runway. Instead, he continued to fly in the traffic pattern at low altitude, and the airplane likely encountered an aerodynamic stall while maneuvering during the base leg.Page 2 of 13 WPR22FA229The pilot’s medical certificate had expired almost 19 years before the accident. According to the autopsy report, he had cardiomegaly, left ventricular hypertrophy, moderate atherosclerosis in one coronary artery, and severe atherosclerosis in his aorta. The airplane’s flight path back to the airport, along with autopsy findings, do not suggest a sudden incapacitating cardiac event and the pilot initially survived the accident. Thus, the pilot’s cardiovascular disease was likely not a factor.The pilot’s toxicology detected sub-therapeutic levels of the sedating antihistamine doxylamine in the blood. This medication can cause drowsiness and diminish performance.The antidepressant amitriptyline and its active metabolite nortriptyline were detected but not quantified in the pilot’s femoral blood, heart blood, and liver tissue. While these substances are associated with side effects such as drowsiness and dizziness, both were detected well below known therapeutic levels. Given their low concentrations and the circumstances of this accident, the effects from the pilot’s use of amitriptyline were not likely a factor.With the exception of a test flight flown by the airplane’s maintenance facility a few days before the accident, this was the first time the airplane had been flown in the 6 months following its annual inspection. It was also likely the first time the pilot had flown during that period. Evidence suggests that the pilot had not received a flight review in almost 18 years. Without the benefit of recurrent training and review, the pilot would likely have had little opportunity to practice airplane procedures and performance capabilities under emergency situations.