Following requests from AOPA, two major GPS manufacturers have added localizer-DME waypoints to their GPS databases. That means pilots can use an IFR-certified GPS receiver in lieu of DME on all localizer, localizer back course, ILS, or any other localizer-type procedure that requires DME.
"AOPA first petitioned for use GPS in lieu of DME back in 1995," said Dennis Roberts, AOPA vice president and executive director of government and technical affairs. "The FAA granted approval in 1998, but some localizer-type approaches were excluded."
That's because GPS databases put the airport waypoint at the center of the airport. DME transmitters are usually co-located with VORs or localizers, not at the airport center. Using fix distances from the airport waypoint would give a pilot inaccurate distance information for an instrument approach.
AOPA members requested the association's help in adding DME waypoints to GPS databases. In July 1999, several manufacturers committed to AOPA that they would add them.
"AOPA can now report that Garmin and Honeywell Bendix/King have added LOC-DME waypoints to their databases," said Roberts. The waypoints are included in Bendix/King models KLN 89B, KLN 90B, KLN 94, and KLN 900, and in Garmin's GPS 155, GPS 155XL, GPS 165, GNC 300, GNC 300XL, GPS 400, GNC 420, GNS 430, and GNS 530.
In addition, UPS Aviation Technologies is working on adding LOC-DME waypoints to the database for their Apollo line of receivers.
"Pilots should contact the manufacturers directly for more information on specific GPS models," said Roberts. "Remember also that the GPS must be certified for IFR and have a current database to be able to use it in lieu of DME for IFR navigation."
AOPA was the pioneer advocate of GPS for civilian aviation beginning back in the 1980s. Its landmark 1990 report to Congress, "The Future Is Now," started a policy debate leading to the adoption of the Department of Defense-originated system for civilian air navigation.
The Aircraft Owners and Pilots Association represents more than 360,000 pilots who own or fly three quarters of the nation's 206,000 general aviation aircraft. More than half of the nation's pilots are AOPA members.
November 1, 2000