TPX-42

Cooperative Surveillance

The TPX-42 beacon interrogator is a military analog interrogator (Identify Friend or Foe (IFF)) system used to detect and report the identity and location of aircraft in a specific volume of airspace. The designation TPX-42 may also refer to a complete beacon and display system. The TPX-42 beacon interrogator subsystem It is used in conjunction with the DOD GPN-20 military airport surveillance radar (ASR) and FAA ASR-9. The TPX-42 is similar to the FAA's Air Traffic Control Radar Beacon Interrogator Models 4 and 5 (ATCBI-4/5). TPX-42 systems provide service to the NAS.

Plans are to replace the TPX-42 beacon systems as the DASR or ASR-11 systems are implemented. Three DOD systems, collocated with ASR-9 primary systems at Hill AFB, may remain operational for the near term. Replacement systems have not been designated.