Approach Basics (GX50/60)

CAUTION

The Apollo GX and the U.S. GPS Satellites

!use the World Geodetic System 1984 (WGS-84) horizontal datum for latitudes

and longitudes. Approach plate or approach procedure data must be referenced to the WGS-84 or North American Datum 1983 (NAD-83) in order to use the approach. NAD-83 is for all practical purposes identical to the WGS-84 datum. All published U.S. and Canadian approach charts meet this criterion. Prior to using the Apollo GX for any GPS approach other than a published U.S. or Canadian approach, you must first verify that the approach charts and approach waypoints use the WGS-84 or NAD-83 reference system. If the approach data is referenced to any other coordinate system, it can result in an unsafe position error.

The Apollo GX database contains approach information. It is very important that the pilot verify that approach data is current prior to use. The approach data contained in the Apollo GX does not replace or eliminate the need for Approach Plates or published Approach Procedures.

Some approach procedures may not be suitable for the Apollo GX operational characteristics and may be omitted from the Apollo GX database. Since an approach must be in the database in order to be selected and flown using the Apollo GX, it is good pre-flight practice to make sure that

the database contains anticipated approaches. Always refer to the charts for a given approach before performing the approach.

9-3