Pitch-fold lock

A blade lock for a tiltrotor aircraft to enable and disable a folding degree of freedom and a pitching degree of freedom of a rotor blade, the blade lock comprising:

• a fold lock adapted to prevent folding of a rotor blade in a fold-lock position and to allow folding of the rotor blade in a pitch-lock position;
• a pitch lock adapted to allow pitch movement of a rotor blade in a fold-lock position and to prevent pitch movement of the rotor blade in the pitch-lock position;
• a spring-loaded link pivotally connected to both the fold lock and the pitch lock and adapted to provide passive, overcenter locking in the fold-lock position;
• and
• an actuator coupled to the pitch lock and adapted to move the pitch lock and the fold lock between the fold-lock and pitch-lock positions, wherein the actuator is a low-profile rotary actuator having an actuator arm and an activation linkage that is coupled to the pitch lock, and wherein the actuator arm and the activation linkage are adapted to provide passive, overcenter locking in the pitch-lock position.