FAA rolled out Wide-Area Multilateration (WAM) surveillance system at Juneau, the agency said last week.
The approach to Juneau is a mountainous area where radar coverage isn’t possible; with WAM controllers are able to safely decrease aircraft separation on approach to five nautical miles. WAM is comprised of a network of small sensors deployed around Juneau. The sensors send out signals that are received and sent back by aircraft transponders. The system triangulates the returning signals to determine the precise location of each aircraft. Controllers are able to see those aircraft on their screens as if they were radar targets.
“This technology will allow more aircraft to fly into Juneau and it will give air traffic controllers the tools they need to safely and efficiently handle these flights,” said FAA Administrator Randy Babbitt.
WAM is being used in the near term while the agency rolls out Automatic Dependent Surveillance – Broadcast (ADS-B). WAM will then serve as a backup to ADS-B in the event of a GPS outage and provide an additional source of traffic broadcast to properly equipped aircraft.