INTRODUCTION

The minimum operational performance requirements for airborne Distance Measuring Equipment (DME) operating within the radio frequency range of 960-1215 MHz specified herein are designed to ensure that aircraft equipment certificated as complying with them will be compatible with the relevant ICAO Standards and Recommended Practices.

Chapter 1 of this document provides information required to understand the need for equipment characteristics and requirements stated in the remaining chapters. It describes typical equipment applications and operational objectives and is the basis for the requirements stated in Chapter 2 to Chapter 4. Definitions essential to proper understanding of this document are also provided in Chapter 1.

Chapter 2 contains general design requirements.

Chapters 3 and 4 contain the minimum performance requirements for the equipment. These requirements define performance under standard operating conditions.

Chapter 5 describes the environmental tests and performance requirements needed to provide a laboratory means of determining the overall performance characteristics of the equipment under conditions representative of those which may be encountered in actual operations.

Chapter 6 details recommended electrical test procedures for demonstrating compliance with the requirements of Chapters 3 and 4.

Chapter 7 describes the performance required of the installed equipment. Ground and flight tests for the installed equipment are included when performance cannot be adequately determined through testing under standard test conditions.

Compliance with these requirements by manufacturers, installers and users is recommended as a means of assuring that the equipment will satisfactorily perform its intended function (s) under all conditions normally encountered in routine aeronautical operations.

It is recognized that any regulatory application of the document in whole or in part is the sole responsibility of appropriate governmental agencies.

Since the measured values of equipment performance characteristics may be a function of the method of measurement. Standard test conditions and methods of test are recommended in this document.