Tunable mass damper assembly for a rotor blade

A tunable mass damper assembly attachable to a rotor blade comprising a leading edge and a trailing edge, the tunable mass damper assembly comprising:

• a base configured to be attached to the rotor blade, the base comprising two base extensions configured to extend from an outer surface of the rotor blade, the two base extensions defining two end stops and an inner area therebetween, the two base extensions supporting a portion of the base that defines a pivot axis;
• and
• a pendulum mass structure comprising:
• a pendulum mass;
• and
• a pendulum arm having a first end coupled to the pendulum mass and a second end pivotably coupled to the base about the pivot axis, the pendulum mass structure configured to pivot about the pivot axis depending on a rotational speed of the rotor blade about a rotor axis, the pendulum mass structure being configured to reduce vibratory forces of the rotor blade induced by rotation of the rotor blade about the rotor axis, wherein the pendulum arm comprises a pendulum arm extension configured to contact the two end stops to limit the rotation of the pendulum arm.