The use of pressure-based altimeters to determine aircraft altitude has been universal across the globe for most of aviation history. This policy examines alternatives provided by Global Navigation Satellite System (GNSS) technologies.
| IFATCA Policy is:IFATCA encourages development of technologies that improve the accuracy of vertical navigation. | 
| See: Resolution B3 – WP 87 – Sofia 2015 | 
Last Update: 29th September 2020
