A method of designing a wind turbine rotor blade. The method includes selecting a gravity load safety factor associated with wind turbine rotor blade fatigue loading due to gravity, that is selected to be less than a defined wind load safety factor associated with wind turbine rotor blade fatigue loading that is not due to gravity. The method includes determining a gravity-corrected design load for wind turbine rotor blade deflection, that is determined based on the selected gravity load safety factor and the defined wind load safety factor. The method includes designing a gravity-corrected wind turbine rotor blade in accordance with the determined gravity-corrected design load.