AIM ¶ 2-3-9 — Airport Location Signs
AIM 2-3-9 explains airport location signs: taxiway, runway, runway boundary, and ILS critical area boundary signs. Study guide for pilot checkrides.
In Plain English
Location signs tell you where you are on the airport surface or signal that you've exited a specific area. Per AIM 2-3-9, there are four types:
- Taxiway Location Sign: Black background, yellow inscription, yellow border. Identifies the taxiway you're currently on. Often paired with direction signs or holding position signs.
- Runway Location Sign: Black background, yellow inscription, yellow border. Identifies the runway you're on. Typically installed where multiple runways are close together and could cause confusion — it complements your magnetic compass.
- Runway Boundary Sign: Yellow background with black inscription depicting the holding position marking. Faces the runway and is visible as you exit. It's your visual cue that you're clear of the runway.
- ILS Critical Area Boundary Sign: Yellow background, black inscription depicting the ILS holding position marking. Located next to the ILS holding marking and seen as you leave the critical area — your cue that you're clear of the ILS critical area.
Knowing these signs helps prevent runway incursions and ILS signal interference during low-visibility operations.
AIM Source Text
FAA AIM ¶ 2-3-92-3-9. 2-3-9. Location Signs
Location signs are used to identify either a taxiway or runway on which the aircraft is located. Other location signs provide a visual cue to pilots to assist them in determining when they have exited an area. The various location signs are described below. Taxiway Location Sign. This sign has a black background with a yellow inscription and yellow border, as shown in FIG 2-3-30 . The inscription is the designation of the taxiway on which the aircraft is located. These signs are installed along taxiways either by themselves or in conjunction with direction signs or runway holding position signs. (See FIG 2-3-35 and FIG 2-3-31 .) FIG 2-3-32 Runway Location Sign FIG 2-3-33 Runway Boundary Sign Runway Location Sign. This sign has a black background with a yellow inscription and yellow border, as shown in FIG 2-3-32 . The inscription is the designation of the runway on which the aircraft is located. These signs are intended to complement the information available to pilots through their magnetic compass and typically are installed where the proximity of two or more runways to one another could cause pilots to be confused as to which runway they are on. Runway Boundary Sign. This sign has a yellow background with a black inscription with a graphic depicting the pavement holding position marking, as shown in FIG 2-3-33 . This sign, which faces the runway and is visible to the pilot exiting the runway, is located adjacent to the holding position marking on the pavement. The sign is intended to provide pilots with another visual cue which they can use as a guide in deciding when they are “clear of the runway.” FIG 2-3-34 ILS Critical Area Boundary Sign ILS Critical Area Boundary Sign. This sign has a yellow background with a black inscription with a graphic depicting the ILS pavement holding position marking as shown in FIG 2-3-34 . This sign is located adjacent to the ILS holding position marking on the pavement and can be seen by pilots leaving the critical area. The sign is intended to provide pilots with another visual cue which they can use as a guide in deciding when they are “clear of the ILS critical area.”
Oral Exam Questions a DPE Might Ask
Q1What does a sign with a black background and yellow inscription/border indicate?
Per AIM 2-3-9, that's a location sign — either a Taxiway Location Sign or a Runway Location Sign — identifying the taxiway or runway on which the aircraft is currently located.
Q2What is the purpose of the Runway Boundary Sign and where is it located?
Per AIM 2-3-9, the Runway Boundary Sign has a yellow background with a black inscription depicting the holding position marking. It's located adjacent to the holding position marking, faces the runway, and gives pilots exiting the runway a visual cue to determine when they are 'clear of the runway.'
Q3How does an ILS Critical Area Boundary Sign differ from a Runway Boundary Sign?
Per AIM 2-3-9, both have yellow backgrounds with black inscriptions, but the ILS Critical Area Boundary Sign depicts the ILS pavement holding position marking and is used to indicate when a pilot is clear of the ILS critical area, rather than clear of the runway.
Related Paragraphs in AIM Chapter 2