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Airport Surface Surveillance Capability (ASSC)

What it does

ASSC improves surface surveillance and situational awareness in all kinds of weather. ASSC is similar to a prior system deployed in the U.S. called the Airport Surface Detection Equipment, Model X (ASDE-X), which is deployed at 35 airports.

With ASSC/ASDE-X, controllers see aircraft and ground vehicles on the airport surface, and on approach and departure paths within a few miles of the airport. ASSC correlates flight-plan information with position displays, providing surveillance data with an accuracy and update rate suitable for:

  • Situational awareness in all weather conditions
  • Departure queuing
  • Conflict detection and alerts
  • Taxi route conformance monitoring


  • Helps prevent runway collisions
  • Improves situational awareness leading to fewer surface delays

How it works

The ASSC system receives input from:

  • ASDE-3 Surface Movement Radar
  • ASSC multilateration remote units
  • ADS-B
  • Airport Surveillance Radar/Mode-S
  • Standard Terminal Automation Replacement System (STARS)

ASSC fuses this data to produce a highly accurate display for controllers to show aircraft and ground vehicles on the surface movement area, and on arrival and departure routes. Pilots with TIS-B and cockpit displays can also receive data derived from ASSC.

ASSC data is also transmitted to other FAA systems listed below.:

  • Surveillance Broadcast Services (SBS)
  • Data Distribution via SWIM/STDDS
  • Runway Status Lights (RWSL)


ASSC is operational at the locations below:

  • Cincinnati (CVG)
  • Cleveland (CLE)
  • Kansas City (MCI)
  • New Orleans (MSY)
  • Pittsburgh (PIT)
  • Portland (PDX)
  • San Francisco (SFO)
  • Anchorage (ANC)

Over the next few years, it will be implemented at:

  • Joint Base Andrews (ADW)

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