A propeller system comprising: a propeller (105, 505, 605, 705); a shaft (165, 565) for rotating the propeller; a clutch mechanism (110, 210, 310, 510, 610, 710) provided around the shaft, wherein the clutch mechanism further comprises: at least one arm (130, 230, 330, 530, 630) pivotably mounted to a first surface of the propeller, wherein the at least one arm is configured to pivot between a first position proximate the shaft and a second position remote from the shaft; at least one biasing element (120, 220, 320, 520, 620) applying a biasing force urging the at least one arm into the first position, the propeller system further comprising: a base (150, 450, 550, 750) through which the shaft extends, the propeller and clutch mechanism configured to rotate together relative to the base; and a first and a second post (152, 452, 552) formed on the base which define an axis along which the propeller is to be substantially aligned when the rotation of the propeller is no longer desired; wherein the at least one arm of the clutch mechanism is configured to contact the first post or the second post when the at least one arm is in the first position so as to align the propeller along the axis when the at least one arm is in the first position, and wherein the clutch mechanism is configured to rotate relative to the base, without contacting the first post or the second post when the at least one arm is in the second position. a propeller (105, 505, 605, 705); a shaft (165, 565) for rotating the propeller; a clutch mechanism (110, 210, 310, 510, 610, 710) provided around the shaft, wherein the clutch mechanism further comprises: at least one arm (130, 230, 330, 530, 630) pivotably mounted to a first surface of the propeller, wherein the at least one arm is configured to pivot between a first position proximate the shaft and a second position remote from the shaft; at least one biasing element (120, 220, 320, 520, 620) applying a biasing force urging the at least one arm into the first position, the propeller system further comprising: a base (150, 450, 550, 750) through which the shaft extends, the propeller and clutch mechanism configured to rotate together relative to the base; and a first and a second post (152, 452, 552) formed on the base which define an axis along which the propeller is to be substantially aligned when the rotation of the propeller is no longer desired; wherein the at least one arm of the clutch mechanism is configured to contact the first post or the second post when the at least one arm is in the first position so as to align the propeller along the axis when the at least one arm is in the first position, and wherein the clutch mechanism is configured to rotate relative to the base, without contacting the first post or the second post when the at least one arm is in the second position. at least one arm (130, 230, 330, 530, 630) pivotably mounted to a first surface of the propeller, wherein the at least one arm is configured to pivot between a first position proximate the shaft and a second position remote from the shaft; at least one biasing element (120, 220, 320, 520, 620) applying a biasing force urging the at least one arm into the first position, the propeller system further comprising: a base (150, 450, 550, 750) through which the shaft extends, the propeller and clutch mechanism configured to rotate together relative to the base; and a first and a second post (152, 452, 552) formed on the base which define an axis along which the propeller is to be substantially aligned when the rotation of the propeller is no longer desired; wherein the at least one arm of the clutch mechanism is configured to contact the first post or the second post when the at least one arm is in the first position so as to align the propeller along the axis when the at least one arm is in the first position, and wherein the clutch mechanism is configured to rotate relative to the base, without contacting the first post or the second post when the at least one arm is in the second position. a base (150, 450, 550, 750) through which the shaft extends, the propeller and clutch mechanism configured to rotate together relative to the base; and a first and a second post (152, 452, 552) formed on the base which define an axis along which the propeller is to be substantially aligned when the rotation of the propeller is no longer desired; wherein the at least one arm of the clutch mechanism is configured to contact the first post or the second post when the at least one arm is in the first position so as to align the propeller along the axis when the at least one arm is in the first position, and wherein the clutch mechanism is configured to rotate relative to the base, without contacting the first post or the second post when the at least one arm is in the second position. wherein the at least one arm of the clutch mechanism is configured to contact the first post or the second post when the at least one arm is in the first position so as to align the propeller along the axis when the at least one arm is in the first position, and wherein the clutch mechanism is configured to rotate relative to the base, without contacting the first post or the second post when the at least one arm is in the second position.