US Patent 9586673 System for aligning a propeller

A motor assembly that includes a motor (102) having a rotatable shaft, a hub coupled to the rotatable shaft, the hub having a propeller indexer to receive a propeller (104), when the propeller is present, a sensor trigger rotatable with the shaft (100) and positioned at a propeller offset angle θPROP from the propeller indexer, and a sensor coupled to the motor and positioned to detect the sensor trigger so that the propeller indexer may be positioned at the propeller offset angle θPROP from the sensor through rotation of the shaft so that said sensor is proximate to the sensor trigger.