Abstract: A derrick assembly capable of conveying pipe sections between a drill string and a rack for storing the pipe sections. The assembly includes a frame having lateral sidewalls and a base together defining an elongated channel having an open outer side opposite to the base. A rack for housing pipe sections is positioned within the channel adjacent to one lateral sidewall leaving part of the channel clear for manipulating the drill string. The rack is formed by a number of elements extending between the base and the open outer side for housing pipe sections oriented generally longitudinally within the channel. A gantry extends across the open outer side of the channel and is movable longitudinally of the channel. The gantry supports a pipe gripping unit for selectively gripping or releasing pipe sections capable of moving towards or away from the base and laterally between the sidewalls.