Rotating unbalanced rotor hubs and installing wind turbine rotor blades

A method for rotating a rotor of a wind turbine that is locked due to an imbalance of the rotor in a rotor plane, the method comprising:

• rotating the rotor using an inching tool to apply torque on a drive train of the wind turbine to reduce the imbalance in the rotor plane;
• removing a locking pin from a locking disc operatively connected to the rotor after reducing the imbalance in the rotor plane;
• rotating the rotor to a desired position;
• wherein rotating the rotor to reduce the imbalance in the rotor plane comprises:
• estimating a direction of a torque load on the rotor due to the imbalance in the rotor plane using one or more sensors, wherein estimating the direction of the torque load comprises measuring a load on or deflection of the locking disc, and wherein estimating the direction of the torque load comprises measuring a distance between the locking disk and a frame of the wind turbine;
• and
• impeding the inching tool from applying torque on the drive train of the wind turbine in the estimated direction of the torque load on the rotor due to the imbalance.