scope:

This specification sets forth the performance requirements and technical characteristics of a Category II/III instrument landing system (ILS). The ILS is an instrument approach landing aid which provides precise electronic guidance to properly equipped aircraft that are making approaches to and landing on airport runways where the ILS is installed. The specification covers the design, manufacture, performance testing, evaluation and delivery of all subsystems and equipment that are required for a complete Category II/III ILS. The Category II/III ILS includes a localizer subsystem, a glide slope subsystem, three marker beacon subsystems, remote indication and control equipment, localizer far field monitor subsystem, remote maintenance monitor system, a portable ILS receiver (PIR), ancillary items and documentation. The equipment to be provided under this specification will be installed by others in existing Government owned shelters. The localizer and glide slope shelters should measure approximately 8' × 12'; marker beacon shelters should measure approximately 6' × 8'.