On February 9, 2020, about 1500 central standard time, a Navion G airplane, N1011M, impacted terrain during a forced landing near Fort Smith, Arkansas. The pilot, and two passengers sustained minor injuries, one passenger sustained serious injuries, and the airplane sustained substantial damage. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, shortly after takeoff about 300 ft above ground level, the engine lost partial power. The pilot lowered the airplane nose and the engine continued to operate. Shortly thereafter, the engine lost total power. The pilot activated the electric fuel boost pump and engine power resumed; however, the engine lost power again within a few seconds. The pilot executed a forced landing to a grass area on airport property. During the forced landing, the airplane impacted terrain and sustained substantial damage to both wings and the fuselage. Postaccident examination of the airplane by a Federal Aviation Administration (FAA) inspector and a mechanic revealed that the fuel selector valve exhibited blue staining on and around the fuel selector valve area. The fuel selector valve was removed for further examination. No fuel was found in any fuel lines or components from the firewall forward to the engine. About 20 gallons of fuel were removed from the airplane fuel tanks during recovery. A review of the aircraft records showed that an annual inspection was completed and airworthiness directive (AD) 2008-05-14, an inspection of the airplane fuel system, was complied with on February 7, 2020, at a total tachometer time of 224.25 hours. The airplane had accumulated 18.2 hours since the inspections. The FAA inspector examined the fuel selector valve and performed vacuum tests on the valve, in accordance with Navion Service Bulletin (SB) No. 106 A, Fuel System - Inspection of the fuel system continued safe operation. Visual examination of the fuel selector valve showed blue staining, consistent with fuel, near the valve stem and inside the airplane were the fuel selector valve was mounted. Multiple vacuum tests, performed to check external and internal leakage, failed the required leak checks per the SB. The AD referred directly to the SB and stated that the fuel selector valve should be repaired or replaced if it failed the tests.