NAVAID Identifier Removal

AIM ¶ 1-1-11 — NAVAID Identifier Removal

AIM 1-1-11 explains why FAA NAVAID identifiers are removed during maintenance and the T-E-S-T code. Study guide for pilot students prepping for checkrides.

In Plain English

When an FAA NAVAID is taken offline for routine or emergency maintenance, technicians remove the coded Morse identifier (and voice, where applicable). The missing ident is your warning that the facility is officially off the air and any signals you receive — even strong, steady ones — may be unreliable for navigation.

Key points to remember:

No ident = don't use it. Even if your CDI centers and the needle behaves, the signal cannot be trusted.
VHF ranges (VORs) may broadcast a T-E-S-T code during maintenance: dash, dot-dot-dot, dash ( - ● ●●● - ). Hearing T-E-S-T means the station is in test mode, not in service.
NOTAMs override the ident. If a NAVAID is NOTAMed out of service, do not fly the procedure even if you hear a normal identifier — during testing the regular ident may briefly be transmitted.

Operationally, this means part of every NAVAID-based procedure is checking NOTAMs in preflight planning and positively identifying the station by ident before tracking it. This is why instructors hammer "tune, identify, monitor" — skipping the ident check on a maintenance NAVAID can lead you off course on an approach or airway.

AIM Source Text

FAA AIM ¶ 1-1-11

1-1-11. 1-1-11. NAVAID Identifier Removal During Maintenance During periods of routine or emergency maintenance, coded identification (or code and voice, where applicable) is removed from certain FAA NAVAIDs. Removal of identification serves as a warning to pilots that the facility is officially off the air for tune-up or repair and may be unreliable even though intermittent or constant signals are received. NOTE- During periods of maintenance VHF ranges may radiate a T-E-S-T code (- ● ●●● -). NOTE- DO NOT attempt to fly a procedure that is NOTAMed out of service even if the identification is present. In certain cases, the identification may be transmitted for short periods as part of the testing.

Oral Exam Questions a DPE Might Ask

Q1Why is the Morse identifier removed from a NAVAID during maintenance?

Per AIM 1-1-11, the identifier is removed to warn pilots that the facility is officially off the air for tune-up or repair. Even if intermittent or constant signals are received, the NAVAID may be unreliable and must not be used for navigation.

Q2What does it mean if you hear a T-E-S-T code (- ● ●●● -) on a VOR?

Per AIM 1-1-11, VHF ranges may radiate a T-E-S-T code during periods of maintenance. It indicates the station is undergoing testing and should not be used for navigation.

Q3If a NAVAID is NOTAMed out of service but you can hear its identifier, can you fly the procedure?

No. Per AIM 1-1-11, do not attempt to fly a procedure that is NOTAMed out of service even if the identification is present, because the ident may be transmitted for short periods during testing.

Related Paragraphs in AIM Chapter 1

¶ 1-1-1

Navigation Aids General

¶ 1-1-10

Simplified Directional Facility

¶ 1-1-12

NAVAIDs With Voice

¶ 1-1-13

NAVAID Outage Reports

¶ 1-1-14

LORAN-C Termination

¶ 1-1-15