Abstract: For an unmanned aerial vehicle (UAV) engine, an exhaust gas temperature control method is provided during operation of the UAV engine to protect exhaust components, particularly lightweight aluminium components, from overheating or melting. The engine is operated with a leaner than stoichiometric air-fuel ratio during low or part engine load conditions. Transition to a richer than stoichiometric air-fuel ratio is made as engine load or engine speed, or both engine load and engine speed, increase(s). At sufficiently low engine loads, the air-fuel ratio can be maintained in a lean ratio region. As demand on the engine causes engine speed and load to increase, the amount of excess air available reduces. The ability to operate lean is reduced and the exhaust gas temperature increases as the mixture becomes richer. In order to obtain the demand power, and keep exhaust temperature below an exhaust gas temperature limit, the air-fuel ratio is transitioned to a richer than stoichiometric region.

Abstract: An unmanned aerial vehicle (UAV) engine (40) lubrication system and lubrication oil heating strategy uses a solenoid actuated electric oil pump (10,42) to deliver lubrication oil to the engine from a lubrication oil reservoir (12,44) by energizing and de-energizing the solenoid (18) to operate a pump mechanism of the electric oil pump. A controller (ECU) (100) can control operation of the electric oil pump, the solenoid maintained energized for a required period of time to cause heating of the oil without continuously pumping the oil. An electric oil pump control strategy can maintain engine speed dependent minimum oil delivery rates, can heat the electric oil pump and oil through extended energized (ON) time of the solenoid, and, by varying the turn on time of the electronic oil pump based on sensed ambient temperature, long time periods can be used to ensure oil delivery for cold temperatures, and shorter times are permitted when necessary in order to reach maximum oil flow rate.

Abstract: This disclosure describes a method of controlling operation of an unmanned aerial vehicle (UAV) having a flight control system comprising: a flight controller for implementing a flight control strategy; and an engine control unit interfaced with the flight controller for controlling engine operation. An engine speed target is set for the flight control system in response to one or more signals communicated by the flight controller to the engine control unit which controls engine operation to achieve the engine speed target by closed loop control over fueling without requiring throttle position control.

Abstract: For an unmanned aerial vehicle (UAV) engine, an exhaust gas temperature control method is provided during operation of the UAV engine to protect exhaust components, particularly lightweight aluminium components, from overheating or melting. The engine is operated with a leaner than stoichiometric air-fuel ratio during low or part engine load conditions. Transition to a richer than stoichiometric air-fuel ratio is made as engine load or engine speed, or both engine load and engine speed, increase(s). At sufficiently low engine loads, the air-fuel ratio can be maintained in a lean ratio region. As demand on the engine causes engine speed and load to increase, the amount of excess air available reduces. The ability to operate lean is reduced and the exhaust gas temperature increases as the mixture becomes richer. In order to obtain the demand power, and keep exhaust temperature below an exhaust gas temperature limit, the air-fuel ratio is transitioned to a richer than stoichiometric region.

Abstract: An unmanned aerial vehicle (UAV) engine (40) lubrication system and lubrication oil heating strategy uses a solenoid actuated electric oil pump (10,42) to deliver lubrication oil to the engine from a lubrication oil reservoir (12,44) by energising and de-energising the solenoid (18) to operate a pump mechanism of the electric oil pump. A controller (ECU) (100) can control operation of the electric oil pump, the solenoid maintained energised for a required period of time to cause heating of the oil without continuously pumping the oil. An electric oil pump control strategy can maintain engine speed dependent minimum oil delivery rates, can heat the electric oil pump and oil through extended energised (ON) time of the solenoid, and, by varying the turn on time of the electronic oil pump based on sensed ambient temperature, long time periods can be used to ensure oil delivery for cold temperatures, and shorter times are permitted when necessary in order to reach maximum oil flow rate.

Abstract: A method of controlling operation of an unmanned aerial vehicle having a flight control system (110) comprising: a flight controller (300) for implementing a flight control strategy; and an engine control unit (117) interfaced with said flight controller (300) for controlling engine (115) operation. An engine speed target is set for said flight control system in response to one or more signals communicated by said flight controller (300) to the engine control unit (117) which controls operation of engine (115) to achieve the engine speed target.