Distance Measuring Equipment and its Evolving Role in Aviation

Abstract

Publisher Summary Two main types of distance measuring equipment (DME)—that is,DME/N and DME/P—have been standardized by the International Civil Aviation Organization (ICAO). This chapter views both DME/N and the new DME/P from a broad systems engineering perspective. Like many other navigation aids, DME is characterized in terms of a signal format, accuracy, coverage, radio frequency assignment, the measurement technique used to extract the DME navigation parameter, and the output guidance information rate. A DME must also satisfy certain levels of signal integrity and availability. The chapter provides the background and historical perspective necessary to view DME in the broader context of air navigation and its specific role in the National Airspace System (NAS). The navigation applications discussed in this chapter are restricted to the air traffic control system as it is defined by the ICAO and as it is implemented in the United States. Therefore, only the domestic enroute, terminal, and approach/landing phases of flight have been addressed. Enroute and approach/landing scenarios have been defined using only the conventional takeoff and land (CTOL) aircraft type. However, DME is not restricted to these applications or to CTOL aircraft. Both helicopter and remote area operations, for example, come under the broad envelope of DME applications.