What is Autofeather system?
Autofeather is a feature of the engines on some turboprop or piston engine aircraft. The auto feather system also allows pilots to reduce the drag of the propellers during an engine failure, therefore, allowing the plane to glide for a longer period of time.
How does propeller feathering work?
Feathering propellers have a mechanism to change the pitch to an angle of approximately 90 degrees. Usually, a propeller is feathered when the engine fails to produce the power needed to turn the propeller. By angling the propeller parallel to the direction of flight, the drag on the aircraft reduces.
What is propeller control system?
basic requirement: For flight operation, an engine is demanded to deliver power within a relatively narrow band of operating rotation speeds. During flight, the speed-sensitive governor of the propeller automatically controls the blade angle as required to maintain a constant r.p.m. of the engine.
What is Autofeather switch?
The autofeather switch will place the props in the feathered position (the leading edge of the propeller blades is fully forward and the blades are essentially parallel to the centerline of the aircraft). Feathering is generally used in multi-engine planes when you either lose or have to shut down and engine in flight.
What is engine feathering?
Feathering a propeller is stopping its rotation with the blades streamlined into the airflow, which reduces drag and allows the airplane to motor on. Multiengine training traditionally has been conducted in piston twins whose engine failures, real or simulated, are easily misdiagnosed and even more easily mismanaged.
What is PEC in ATR?
The Propeller Electronic Control (PEC) (Figure 12.22-4) is a dual channel microprocessor-based controller which uses inputs from the aeroplane, propeller control system sensors, and the engine control system to control propeller pitch and speed.
What is an Unfeathering accumulator?
3) Unfeathering accumulators Found in many multi-engine training aircraft, the unfeathering accumulator stores oil under pressure when you move a propeller lever into the feather detent position. This helps the propeller start windmilling again, and helps the engine to restart.
How does a constant speed propeller work?
Constant speed propellers work by varying the pitch of the propeller blades. As the blade angle is increased, it produces more lift (thrust). At the same time, more torque is required to spin the prop, and the engine slows down.
How do propeller counterweights work?
Variable pitch propellers have either counterweights or a lock to limit unwanted blade angle movement to low pitch after failures. Counterweights are attached to the blade at a position that will cause the centrifugal loads on the counterweights to drive the blades towards higher pitch (towards feather).