The TERRA-JACK is a directional rod pusher. It pushes a drill rod through the ground. The drill head cuts a bore channel into the ground. This is only possible in displaceable underground as clay, sand or loose gravel. The drill head has a asymmetric directional area at its front. The rods can be rotated with the hand lever, this rotates the directional area of the drill head. This allows steering or straight drilling. The electrical sonde in the drill head makes continuous locating of the drill head possible. You can steer the bore by stopping the rotation of the drill head, when the directional area points into the required direction. If the drill head is pushed through the ground without rotation, the drill head steers sideways along its directional area. This allows bending radiuses of R (min) = 25 m (82 ft). For straight drilling, the rod must be rotated during moving forwards.