Overview
On 12 February 2018, a Beechcraft F33A Bonanza was involved in an accident at Stokrooie (Hasselt), Belgium. The aircraft was operated by the pilot-owner and carried one passenger. The Air Accident Investigation Unit of Belgium (AAIU(Be)) conducted the investigation and published its final report on 12 February 2021.
Investigation
The investigation included a detailed examination of the wreckage, engine, airframe, and fuel system. The fuel selector valve and its history were reviewed. Meteorological conditions were analyzed using synoptic data, forecasts, and observed weather. Toxicological tests were performed on both the pilot and passenger. The flight track and altitude were reconstructed from available navigation logs and other data.
Findings
The investigation identified an undesirable event involving a restriction in the air induction and fuel starvation. Recovery actions taken by the pilot were analyzed, and mitigation and survivability aspects were considered. The report highlighted several safety issues, including the installation of upper torso restraints, the operation of flights at low altitudes without secured restraints, the complexity of retrofitting restraint kits, and the design of fuel selector valves based on old certification standards. Additional safety factors included the risks of changing fuel tanks at low altitude and the criticality of engine power loss at low altitude.
Safety Recommendations
The report included safety recommendations addressing the identified issues, focusing on restraint systems, flight operations at low altitude, and fuel system design. No recommendations were made regarding air traffic control or navigation aids.