- The Receiving - Decoding Group (RDG) AN/ARA-63 (Airborne Microwave Landing Subsystem) is used in conjunction with the surface based Transmitting Sets AN/SPN-41 or AN/TRN-28 to provide either primary or backup instrument approach capability for aircraft. The transmitting set provides guidance information for any number of aircraft at a range to 20 miles. The information is used by the pilot to maintain the aircraft on the approach path toward the touchdown point.

The transmitting set consists of two scanning beam antennas, their associated pulse transmitters and control equipment. At a range of 20 miles, the azimuth scanning beam sweeps an area approximately 8 miles wide, while the elevation or glide path beam is approximately 4 miles high.

The coded, angular information, from the ship or shore installation, is received in the aircraft Radio Receiver, decoded by the Pulse Decoder, and displayed on a crosspointer meter. The vertical needle of the crosspointer is used for azimuth guidance and the horizontal needle for vertical guidance when an aircraft is approaching the carrier or runway. With both needles centered, the aircraft is at the deck or runway centerline and the reference glide path. In the event of a failure or inconsistent data, a flag will be presented to the pilot in conjunction with a fly-up or a fly-right needle deflection.