Autofeather is a feature of the engines on some
turboprop
A turboprop is a turbine engine that drives an aircraft propeller.
A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. ...
or piston engine aircraft. When the power being produced by the engine drops to the point where it is not contributing to thrust, the propeller will go into a
feathered mode to reduce
drag.
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.
An automatic feathering system was first introduced on the
Martin 4-0-4
The Martin 4-0-4 was an American pressurized passenger airliner built by the Glenn L. Martin Company. In addition to airline use initially in the United States, it was used by the United States Coast Guard and United States Navy as the RM-1G ...
aircraft, a piston engine airplane. The system was designed to automatically feather an engine that failed during takeoff or initial climb.
It is not used during cruise.
Aircraft engines
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