scope:

Purpose. The purpose of the portable transceiver is to provide emergency air/ground communication capability for air traffic control (ATC) operations during catastrophic failure of the normal radio communication system. Communication failure might be experienced during loss of ATC facility power, or the failure of the inter/intra facility connectivity to the air/ground radio communications equipment. It also provides emergency radio communication during those times that a facility must be abandoned, e.g., in the event of facility fire, bomb threat, or severe weather. The portable transceiver provides the air/ground communication capability during the first critical 30 minutes after these events occur.