WAAS Signal May Be Spotty
An orbit change by one of two satellites providing Wide Area Augmentation System (WAAS) signals for precision GPS approaches could result in the vertical component of those signals being unavailable at times in the next couple of months. According to AOPA, when the move is finished, WAAS service will be lost to a couple of Maine airports until the fall. Inmarsat, which owns the satellite, is moving it further west to boost coverage there. As the satellite makes its way, signals necessary for LPV (lateral precision with vertical guidance) approaches may not be there. NOTAMs will be issued. Most pilots and airports will hardly notice the transition (non-WAAS GPS units use the Air Force's constellation of 24 satellites), but those who've become accustomed to the LPV approaches at Portland, Maine, and Concord, N.H., will have to make other plans for the summer. The westward move of Inmarsat's satellite will eliminate the WAAS signal to those airports and it won't be until the fall, when the FAA starts renting space on a third satellite, that the gap will be filled.