For a complete summary of the feature changes and enhancements, click Here.In short, WAAS approach-capable GPS units provide lateral and vertical guidance to many airports that have never had a precision approach. 2007, there are 640 GPS-based LPV approaches with minimums as low as 200 feet and 1/2 mile visibility.In addition, aircraft with more recent glass cockpit technology (e.g.EX5000 and G1000) have not been completely addressed for the WAAS upgrades.It is very important that pilots, aircraft owners and operators ensure installations are performed by skilled, experienced technical personnel to provide the safest flying environment and experience.
Avionics installations and interfacing can sometimes be very complex.
A terrain database for terrain awareness is included a standard feature.
Most importantly, the WAAS GPS receiver allows pilots to use the GNS-400W/500W units for primary navigation and vertical guidance for LPV, L/VNAV, and LNAV V approaches.
A WAAS upgraded 400/500 series unit will not crossfill to a non-WAAS 400/500 series unit.
One subject that many people upgrading to WAAS may overlook involves the GPS navigators distance from the pilot's primary field of view.