In-the-hole drill

A mobile drilling apparatus, the apparatus comprising a frame, the frame having a distal end and a proximal end, a column pivotally mounted on the distal end of the frame, the column movable in a first arc substantially normal to the distal end of the frame, the first arc defined from a proximal lowered position to a distal upright vertical position, anchoring means disposed within the top of the column, a pivot assembly affixed on the distal end of the frame, a box frame mast supported by the column and affixed to the pivot assembly, the mast movable along the first arc in a fixed relationship with the column and along a second arc substantially normal to the first arc independently of the column, a concentric double acting cylinder mounted within the mast, a carrier slidably registered with the mast and ganged with the cylinder so as to move therewith, a stress relief trunnion engaging the cylinder, the stress relief trunnion mounted within a bracket disposed within the mast, the bracket affixed to the carrier, a drill motor affixed to the carrier, and means for securing the apparatus against movement.