Types of Aircraft Propellers
Like other forms of aviation technology, aircraft propellers are not fixed and unchanging, but instead evolved, changed, and improved over the years, developing into different types depending on the needs of their users. In this blog, we will break down and examine some of the most common types of propellers.
The first type of propellers developed were fixed pitch propellers. As their name implies, fixed pitch propellers cannot change their pitch (the angle the propeller blades face) and are typically made from a single piece of material. Fixed-pitch propellers were first made from wood, in the years before World War 2. Wooden propellers are not carved from a single piece of wood, but instead five or more separate plies of wood that are laminated together to prevent warping.
Modern innovations have created other types of propellers. The first are controllable pitch propellers, which have a hydraulic system built into the propeller. This allows the pilot to adjust the pitch of the propeller while in flight, which gives them more control over the handling and flight characteristics of the aircraft. Propeller adapters also have a big advantage over some traditional propellers.
Constant speed propellers use hydraulic or electrical means to adjust the blade pitch, which lets them compensate for increased or decreased power. This occurs automatically, so that if engine power increases the blade angle increases as well, and if the engine power decreases the blade angle decreases to match it. This is done to keep engine RPM constant, which improves the engine’s health.
Two-position propellers have two preset pitch angles that the pilot can switch between freely while in flight. Reversing propellers are constant speed propellers that are able to add negative pitch to the blades, which produces negative thrust, and effectively turns the propeller into a brake of sorts. This is used to shorten the amount of runway needed when landing larger aircraft.
Full feathering propellers are constant speed propellers that have the ability to turn in the wind in the event of engine failure. This helps eliminate drag and windmilling.
-
john symond
-
Posted on August 6, 2019
aviation
