This document provides the guidance and detailed information on standard configurations and equipment. Use this document when designing, planning, constructing, and installing new systems. This document applies to Army and Air National Guard and Army and Air Force Reserve bases with responsibility for maintaining their airfield facilities. Existing systems and components are not required to be upgraded to these standards unless as part of a major rehabilitation. It is also important to note that the absence of a formerly FAA-approved NAVAID or piece of equipment from the current AC 150/5345-53, Appendix 3 Addendum is not an indication that this equipment is no longer approved for use. It means that particular NAVAID or piece of equipment is no longer manufactured. Much of this equipment is still supported for repairs by a sub-party of the former manufacturer and this NAVAID/piece of equipment may be more reliable and powerful than the one currently listed in the AC. Contact AFCEC/COSM if told that a NAVAID or piece of equipment is no longer approved for use. Beacons are one example of this situation.