An aircraft control surface operating device for operating a control surface provided on an aircraft body portion to move between a retracted position and at least one extended position, the aircraft control surface operating device comprising: a control surface mounting assembly configured to movably secure the control surface to the aircraft body portion; a drive arm configured to be rotatably mounted to the aircraft body portion so as to be rotatable about a drive axis relative to said aircraft body portion; an actuator configured to rotate the drive arm in a first direction about the drive axis and a second direction about the drive axis, the second direction being opposite to the first direction, and a drive link having a control end connected to the control surface mounting assembly via a control bearing joint, and a driven end connected to the drive arm via a drive bearing joint, wherein the drive bearing joint includes a substantially spherical drive bearing rotatably held within an opening defined through the drive link at the driven end, the drive bearing including a pair of drive bearing connecting portions provided opposite to one another on a surface of the drive bearing, the drive bearing being fixedly connected to the drive arm at the drive bearing connecting portions such that the drive link is rotatable about the drive bearing relative to the drive arm, the control bearing joint includes a substantially spherical control bearing rotatably held within an opening defined through the drive link at the control end, the control bearing including a pair of control bearing connecting portions provided opposite to one another on a surface of the control bearing the control bearing being fixedly connected to the control surface mounting assembly at the control bearing connecting portions such that the drive link is rotatable about the control bearing relative to the control surface mounting assembly, an axis of rotation of the drive link about the drive bearing is nonparallel to an imaginary line connecting the drive bearing connecting portions, and an axis of rotation of the drive link about the control bearing is parallel to an imaginary line connecting the control bearing connecting portions, and the drive link connects the drive arm and the control surface mounting assembly such that rotation of the drive arm in the first direction about the drive axis causes the drive link to exert a retracting force on the control surface mounting assembly, and rotation of the drive arm in the second direction about the drive axis causes the drive link to exert an extending force on the control surface mounting assembly. a control surface mounting assembly configured to movably secure the control surface to the aircraft body portion; a drive arm configured to be rotatably mounted to the aircraft body portion so as to be rotatable about a drive axis relative to said aircraft body portion; an actuator configured to rotate the drive arm in a first direction about the drive axis and a second direction about the drive axis, the second direction being opposite to the first direction, and a drive link having a control end connected to the control surface mounting assembly via a control bearing joint, and a driven end connected to the drive arm via a drive bearing joint, wherein the drive bearing joint includes a substantially spherical drive bearing rotatably held within an opening defined through the drive link at the driven end, the drive bearing including a pair of drive bearing connecting portions provided opposite to one another on a surface of the drive bearing, the drive bearing being fixedly connected to the drive arm at the drive bearing connecting portions such that the drive link is rotatable about the drive bearing relative to the drive arm, the control bearing joint includes a substantially spherical control bearing rotatably held within an opening defined through the drive link at the control end, the control bearing including a pair of control bearing connecting portions provided opposite to one another on a surface of the control bearing the control bearing being fixedly connected to the control surface mounting assembly at the control bearing connecting portions such that the drive link is rotatable about the control bearing relative to the control surface mounting assembly, an axis of rotation of the drive link about the drive bearing is nonparallel to an imaginary line connecting the drive bearing connecting portions, and an axis of rotation of the drive link about the control bearing is parallel to an imaginary line connecting the control bearing connecting portions, and the drive link connects the drive arm and the control surface mounting assembly such that rotation of the drive arm in the first direction about the drive axis causes the drive link to exert a retracting force on the control surface mounting assembly, and rotation of the drive arm in the second direction about the drive axis causes the drive link to exert an extending force on the control surface mounting assembly.