Course Deviation Indicator

CHAPTER ONE

INSTRUMENT FLIGHT RULES WORKBOOK

113.

COURSE DEVIATION INDICATOR

The CDI displays radial information received by the aircraft's VOR or TACAN receiver (Figure

1-26). The CDI indicates the aircraft's position in relation to the selected course. A toggle

switch on the instrument panel above the CDI marked VOR-TACAN allows the pilot to select

either the VOR or the TACAN navigation system as the source of information displayed on the

CDI.

Figure 1-26 IND-350

In review, a radial is one of 360 magnetic bearings which radiate from a VOR or TACAN

facility and the radial the aircraft is on is indicated by the tail of the VOR/TACAN needle.

Review Figure 1-27.

1-32 INTRODUCTION TO AIRBORNE NAVIGATION AND COMMUNICATIONS

EQUIPMENT AND PRINCIPLES OF OPERATION