GBAS has evolved from a concept and prototype technology into an operational precision-approach solution at a growing number of airports worldwide. Today, GBAS supports CAT I GLS approaches at selected sites, with ongoing work toward dual-frequency, multi-constellation systems and CAT II/III/autoland capability.

Operational GBAS installations are concentrated at major international airports and selected regional hubs that benefit from:

• Multiple runways and complex operations

• ILS congestion or siting challenges

• Interest in advanced PBN and low-visibility operations

Most operational systems today are:

• GAST-C, single-frequency, GPS-based

• Certified for CAT I minima

• Supporting a set of GLS approaches that mirror or complement existing ILS procedures

Several additional airports are in various stages of:

• Procurement and installation

• Flight trials and validation

• Regulatory and operational approval