Who establishes the recommended operating time limit (TBO) between overhauls of a turbine engine for general aviation?

The recommended operating time limit, known as Time Between Overhaul (TBO), is determined primarily by the engine manufacturer. This is because the manufacturer conducts extensive testing and analysis on their engines to establish guidelines that ensure safety, reliability, and optimal performance. They take into consideration various factors such as materials, design, and expected usage to determine how long an engine can operate before needing an overhaul.

These recommendations are based on the manufacturer's experience and data collected during the engine's lifecycle, including testing under various conditions and service histories. Consequently, pilots, maintenance personnel, and operators rely on the manufacturer's TBO specifications to schedule maintenance and ensure the safe operation of the aircraft.

While the FAA provides regulations and oversight for aviation safety, it does not set specific TBO limits for engines. Instead, the FAA typically endorses and requires adherence to manufacturer's guidelines and maintenance schedules, allowing the manufacturers' expertise to guide the recommendations. Therefore, the engine manufacturer's role is crucial in establishing the TBO that maintains operational integrity in general aviation.