The Wide Area Augmentation System (WAAS) is an extremely accurate navigation system developed for the Federal Aviation Administration (FAA) which compliments GPS. WAAS allows the U.S. National Airspace System (NAS) to provide precision vertical and horizontal navigation approach operations as well as provide services for all classes of aircraft in all phases of the flight. 

Hosted on SES-15 and other commercial satellites to provide system resiliency, these navigation hosted payloads receive and broadcast messages on GPS frequencies to provide safety-of-flight information across the NAS.


Compared to using traditional GPS for flight planning, terminal, and enroute operations, the WAAS system:

  • Allows use of LNAV/VNAV minima without temperature restrictions 
  • Provides vertically-guided approach procedures capability at airports that do not have ground-based navigational aides
  • Is not affected by snow reflections that can impact ILS operations 
  • Allows RNAV (GPS) approaches to be used for alternate airport flight planning
  • Increases number of alternate airport options which improves flight planning flexibility
  • Satisfies equipment requirements for ‘T’ and ‘Q’ routes
  • Eliminates RAIM check requirement per AC 90-100A 
  • Provides three additional ranging sources (from WAAS GEOs)
  • Enables extension of terminal mode operations for both departure and arrival to beyond 30 nautical miles from the airport reference point
  • Increased accuracy and availability 
  • Eliminates ILS critical areas
  • Enables ADS-B



For more information, please contact us at or call at 703-610-1000.