An attitude control experiment of a spacecraft using six single-gimbal control moment gyros is described in this paper. The control moment gyros are arranged in a twin-triangular pyramid configuration, where internal singular states are all passable. By using the passable characteristics of the configuration, a steering law which calculates the gimbal angular rates from the attitude control torque is derived. A ground experiment by the steering law is executed with a three-axis motion simulator and is compared with that by the singular direction avoidance steering law. The usefulness of the proposed steering law is verified by the ground experiments as well as the numerical simulations.