Can any aviation GPS navigator use WAAS corrections?
A. No. In order to receive and decode the WAAS signal, an aircraft GPS navigator must have a specially designed WAAS GPS engine and other advanced features. The FAA has created a new technical certification classification for such navigation equipment, TSO C-145a or C-146a. The TSO C-129a GPS navigators that are prevalent in aviation today are not certified to receive or use the WAAS signal corrections, although they can “see” the WAAS satellites as any other GPS satellite.
