Figure 3-53. Four-blade propeller. Figure 3-54. Three-blade propeller. Propellers typically consist of two, three, or four blades.  [Figures 3-53  and  3-54]  Propellers can be ground adjustable  or fixed pitch. Variable pitch flight propellers are not allowed  on LSA. The pitch should be properly set for your WSC  aircraft to provide the recommended rpm of the engine at  full power. The POH should be consulted if there is any  question about the propeller rpm and adjusting or replacing  the propeller. Propellers are specifically matched to the  engine power, gear reduction and speed range of the aircraft.  Therefore, not just any propeller may be put on any engine.  The POH requires specific propellers that are matched for  each aircraft.  As with an airplane propeller, the WSC aircraft propeller  turns at such high speeds that it becomes invisible when in  motion. The dangers of a turning propeller require every  pilot to maintain the highest level of safety and respect for  the consequences of body parts, pets, and debris coming  in contact with a rotating propeller. Debris on the takeoff/ landing field is a danger to the propeller, as well as to the  people who may be in the prop-wash area behind or on the  side of the propeller. Stones, small pieces of metal, and  sticks can become dangerous projectiles if kicked into the  propeller during start-up, taxi, takeoff, and landing. Just as  with any airframe or wing component of a WSC aircraft, if the  propeller becomes damaged, nicked, or dinged, the aircraft’s  performance can be greatly affected. Some pilots elect to use  tape or rock deflector guards to protect the leading edge from  rock/debris damage. Regardless, taking proper care of the  propeller is as critical as proper engine and wing care. 3-21