Validation projects

Precision approaches using GBAS CAT II/III based on GPS L1

Release: 2014

Reference: -

Location: Toulouse


GBAS augments the global navigation satellite system (GNSS) signals by sending the positioning corrections to aircraft for precision approach and landing. Precision approaches using GBAS offer possibilities to develop new approach paths and to enable all-weather access to airports where no ILS is installed. In particular, GBAS used for Category II/III approaches (1000 feet or 300 metres) or less of runway visual range offers a viable and cost-effective solution for low visibility operations, overcoming ILS operational limitations such as for critical and sensitive areas. GBAS is also more cost-effective since its single ground station can serve several runway ends.

Validation results

Exercises in Toulouse validated airport operations and the interoperability between air and ground systems during approach and landing. The results of these exercises were as follows:

• Sustained accuracy for aircraft guidance on final approach and good performance in operational conditions, with no interference from previous landing aircraft;

• Interoperability between air and ground systems during approach and landing;

• Increased runway throughput, while maintaining safety and human performance levels, and increased resilience in poor weather conditions.


The validation results for this solution are conclusive and sufficient to support a decision for industrialisation.