VORTAC Navigation Aid

AIM ¶ 1-1-6 — VORTAC Navigation Aid

AIM 1-1-6 explained: VORTAC combines VOR and TACAN to provide VOR azimuth, TACAN azimuth, and DME at one site. Study guide for pilot students.

In Plain English

A VORTAC is a single navigation facility that combines two components — a VOR and a TACAN — at one site. Even though it has multiple components, frequencies, and antennas, the FAA treats it as one unified NAVAID.

A VORTAC delivers three distinct services simultaneously:

VOR azimuth (bearing information for civil aircraft)
TACAN azimuth (bearing information for military aircraft)
TACAN distance (DME) (distance information available to both civil and military users)

Why it matters: When you tune a VORTAC for VOR navigation, your civil DME receiver actually pulls distance from the TACAN side of the facility. To make sure both signals come from the same ground station, the VOR and TACAN are each identified by a three-letter Morse code and the signals are interlocked. The VHF (VOR) and UHF (TACAN) frequencies are also paired under a national plan, so selecting the VOR frequency automatically gives you the correct DME channel — simplifying cockpit operation.

AIM Source Text

FAA AIM ¶ 1-1-6

1-1-6. 1-1-6. VHF Omni-directional Range/Tactical Air Navigation (VORTAC) A VORTAC is a facility consisting of two components, VOR and TACAN, which provides three individual services: VOR azimuth, TACAN azimuth and TACAN distance (DME) at one site. Although consisting of more than one component, incorporating more than one operating frequency, and using more than one antenna system, a VORTAC is considered to be a unified navigational aid. Both components of a VORTAC are envisioned as operating simultaneously and providing the three services at all times. Transmitted signals of VOR and TACAN are each identified by three-letter code transmission and are interlocked so that pilots using VOR azimuth with TACAN distance can be assured that both signals being received are definitely from the same ground station. The frequency channels of the VOR and the TACAN at each VORTAC facility are “paired” in accordance with a national plan to simplify airborne operation.

Oral Exam Questions a DPE Might Ask

Q1What is a VORTAC and what services does it provide?

Per AIM 1-1-6, a VORTAC is a unified navigational facility consisting of two components — VOR and TACAN — at one site, providing three services: VOR azimuth, TACAN azimuth, and TACAN distance (DME).

Q2How can a pilot be sure the VOR azimuth and DME information are coming from the same ground station?

Per AIM 1-1-6, the VOR and TACAN signals are each identified by a three-letter Morse code transmission, and the identifications are interlocked so pilots using VOR azimuth with TACAN distance can be assured both signals come from the same ground station.

Q3Why doesn't a pilot have to separately tune the DME when using a VORTAC?

Per AIM 1-1-6, the VOR and TACAN frequency channels at each VORTAC are paired according to a national plan, so selecting the VOR frequency automatically pairs the correct TACAN/DME channel, simplifying airborne operation.

Related Paragraphs in AIM Chapter 1

¶ 1-1-1

Navigation Aids General

¶ 1-1-10

Simplified Directional Facility

¶ 1-1-11

NAVAID Identifier Removal

¶ 1-1-12

NAVAIDs With Voice

¶ 1-1-13

NAVAID Outage Reports

¶ 1-1-14