Abstract: A microwave landing system employing a phased array antenna for the generation of narrow, scanning guidance beams in which broad beam antennas used for transmitting identification signals, fly-left, fly-right guidance signals and the like with broad coverage are eliminated by applying spoiling phases to the phase shifters of the array thereby broadening the beam shape of the array to a pattern substantially identical to the pattern of a broad beam antenna formerly used. The spoiling phases are applied to the array in the time slots allocated to transmission of broad beam signals and the broad beam signals are then transmitted by the array. The spoiling phases are removed from the array during the time slots allocated to transmission of narrow scanning beams and the narrow scanning beams are then transmitted by the array. Computation of spoiling phases to provide particular patterns for particular antennas is disclosed.