Abstract: A self-adjusting slide assembly is provided for mounting a weight on gear switch to an aircraft. The slide assembly is particularly adapted for mounting on a skid equipped helicopter for responding to vertical oscillatory deflection of a cross tube of the skid landing gear. A mounting bracket is attached to the underside of the helicopter for supporting a back plate and a pair of clamp plates. A C-shaped slide member has a flange mounted between the back plate and clamp plates so as to slide vertically. Take-off and landing stresses cause the cross tube to exhibit vertical oscillatory deflection between an upper arm and a lower arm of the slide member. A microswitch mounted on the lower arm is actuated when the cross tube contacts a bottom bumper on the lower arm while the helicopter is fully on skid gear.