AIM ¶ 1-1-1 — Navigation Aids General
AIM 1-1-1 explains air navigation aid ownership, FAA authority, the Chart Supplement, and why pilots must disregard NOTAM'd inoperative NAVAIDs.
In Plain English
AIM 1-1-1 introduces the air navigation aids (NAVAIDs) pilots use every day. Key points to know:
- Multiple owners/operators provide NAVAIDs: the FAA, the military, private organizations, individual states, and foreign governments.
- The FAA has statutory authority to establish, operate, and maintain NAVAIDs and to set standards for any aid used for instrument flight in federally controlled airspace.
- All these aids are listed in the Chart Supplement (formerly the A/FD), which is your go-to reference for facility data.
- When a ground-based transmitter (such as a glideslope, VOR, or NDB) has its primary signal generator inoperative, your cockpit display may show momentary erroneous indications that look normal.
- If a NAVAID has been flagged unusable or inoperative by NOTAM (or otherwise), you must disregard the indication even if it appears valid.
Operationally, this means always check NOTAMs before flight, cross-check NAVAIDs against another source, and never trust a needle from a station you know is down.
AIM Source Text
FAA AIM ¶ 1-1-11-1-1. 1-1-1. General
Various types of air navigation aids are in use today, each serving a special purpose. These aids have varied owners and operators, namely: the Federal Aviation Administration (FAA), the military services, private organizations, individual states and foreign governments. The FAA has the statutory authority to establish, operate, maintain air navigation facilities and to prescribe standards for the operation of any of these aids which are used for instrument flight in federally controlled airspace. These aids are tabulated in the Chart Supplement. Pilots should be aware of the possibility of momentary erroneous indications on cockpit displays when the primary signal generator for a ground-based navigational transmitter (for example, a glideslope, VOR, or nondirectional beacon) is inoperative. Pilots should disregard any navigation indication, regardless of its apparent validity, if the particular transmitter was identified by NOTAM or otherwise as unusable or inoperative.
Oral Exam Questions a DPE Might Ask
Q1Who owns and operates the navigation aids pilots use in the U.S. airspace system?
Per AIM 1-1-1, NAVAIDs are owned and operated by a variety of entities: the FAA, the military services, private organizations, individual states, and foreign governments.
Q2What authority does the FAA have over navigation aids, and where can pilots find them listed?
Per AIM 1-1-1, the FAA has statutory authority to establish, operate, and maintain air navigation facilities and to prescribe standards for any aid used for instrument flight in federally controlled airspace. These aids are tabulated in the Chart Supplement.
Q3If a VOR has been NOTAM'd as inoperative but you receive what looks like a valid indication, what should you do?
Per AIM 1-1-1, pilots should disregard any navigation indication—regardless of its apparent validity—if the transmitter was identified by NOTAM or otherwise as unusable or inoperative, because momentary erroneous indications can occur when the primary signal generator is inoperative.
Related Paragraphs in AIM Chapter 1