The Viewpoint “WAAS: Vital for NextGen and It Needs Help” (AW&ST June 10, p. 58) describes the Wide Area Augmentation System (WAAS) as being in need of expansion to help NextGen. I believe Ernest Edwards's terminology is a little misplaced. WAAS is a Space-Based Augmentation System (SBAS) to GPS which already covers North America and cannot be expanded there. What can be expanded is the charting of Required Area Navigation (RNAV) instrument approaches to Localizer Precision ...


You must be a paid subscriber to access "WAAS Constrained".


Current Aviation Week Intelligence Network (AWIN) enterprise and individual members: please go to for access.


Not currently a subscriber? Click on the "Learn More" button below to view subscription offers.

Already registered? here.