73 Engine Fuel and Control
TTP B1-L3 ATA 73 Beech 90 Series B2-L1 Engine Fuel and Control ENGINE FUEL AND CONTROL - DESCRIPTION AND OPERATION Description A. PT6A-21 Engines The fuel control system consists of an oil-to-fuel heater, fuel pump, fuel control unit, flow divider and dump or purge valve, dual fuel manifold with 14 simplex nozzles, fuel drain valves and interconnecting pneumatic sense lines. For purposes of description, the system also includes the power turbine governor. The fuel pump delivers fuel to the fuel control unit (FCU), which determines the correct fuel schedule for engine steady-state operation and acceleration. The flow divider supplies the metered fuel flow to the primary and secondary manifolds as required. Full propeller control during normal operation is provided by a governor which incorporates a propeller governor (CSU) section and a power turbine governor (Nf) section. The Nf governor section provides powe...