As the FAA moves ahead it with its plans to decommission about one-third of the existing network of VORs in the continental U.S. (for more information, see Another Update on VOR Decommissioning and its related posts), a new type of navaid–a stand-alone DME facility–is appearing on aeronautical charts.
Here’s an example southwest of Las Vegas, NV. Note the identification and frequency box for the GOODSPRINGS DME (GOG). The site of the transmitter is shown by the small blue box indicated by the red arrow.
Here’s the same facility on a low-altitude IFR chart:
You can read more about these stand-alone DME facilities in DME Facilities – Charting and MAGVAR Issues (PDF), which describes the discussions of the Aeronautical Charting Forum, an FAA-industry group.
These stand-alone DMEs are primarily for use by aircraft with DME-DME area navigation equipment, and in many cases, they are left over when the VORs they were associated with are shut down. Where necessary, new DMEs will be added to support RNAV procedures based on DME-DME as an alternative to GPS. As you can see from the chart, these DMEs do not provide azimuth (course) information like a VOR-DME or VORTAC. They are simply DMEs.
If, like most IFR pilots flying typical GA aircraft, you use GPS as your primary navigation source, these charted stand-alone DMEs are of most interest as fixes that you can include in a route or flight plan. If you still have a DME receiver in your airplane, you can tune, identify, and reference these DMEs as you fly.