Taxiway Markings and Airport Signs

13.taxiway-and-signage. Taxiway Markings and Airport Signs

Taxiway markings, lighting, and airport signs form an integrated system designed to help pilots navigate safely between the runway and parking areas, prevent runway incursions, and identify hold positions where ATC clearance is required. Every student pilot must be able to recognize and correctly interpret these visual aids before solo operations at a towered or non-towered airport.

Taxiway Markings

Taxiway markings are painted yellow to distinguish them from the white markings used on runways.

• Taxiway centerline — A continuous yellow stripe that provides a visual cue allowing the pilot to keep the aircraft centered. Following the centerline ensures wingtip and tail clearance from objects along the taxiway edge.
• Enhanced taxiway centerline — A parallel pair of dashed yellow lines flanking the centerline for the last 150 feet prior to a runway holding position marking. It serves as an additional cue that the aircraft is approaching a runway.
• Taxiway edge markings — Used to define the edge of a taxiway when the edge does not correspond with the edge of the pavement. Two continuous yellow stripes (each 6 inches wide, 6 inches apart) indicate that the adjacent pavement is not intended for aircraft use. Two dashed yellow stripes indicate the adjacent paved surface, though usable, is not intended as a taxiway (e.g., an apron edge).
• Taxi shoulder markings — Yellow stripes on paved shoulders that may not support aircraft.
• Surface-painted taxiway direction signs — Yellow background with black inscription, used where it is impractical to install signs adjacent to the taxiway.
• Surface-painted location signs — Black background with yellow inscription, used to supplement location signs near taxiway intersections.

Holding Position Markings

Holding position markings identify the location at which an aircraft must stop when it does not have clearance to proceed onto the runway or into a critical area.

• Runway holding position markings — Four yellow lines, two solid and two dashed, extending across the width of the taxiway. The solid lines are always on the side where the aircraft must hold. When approaching the runway, the aircraft must not cross the solid lines without an ATC clearance (at a towered field). When exiting the runway, the aircraft is clear of the runway only when it has crossed the dashed side and the entire aircraft is past the solid lines.
• Holding position markings for ILS critical areas — Two yellow solid lines spaced 2 feet apart connected by pairs of solid lines spaced 10 feet apart extending across the width of the taxiway (a "ladder" pattern). When ILS critical area protection is in effect, aircraft must hold short of these markings.
• Holding position markings for taxiway/taxiway intersections — A single dashed yellow line across the taxiway, used when ATC normally holds aircraft short of an intersecting taxiway.

Airport Signs

The FAA recognizes six types of airport signs, each with a specific color scheme:

• Mandatory instruction signs — Red background with white inscription. They denote an entrance to a runway, critical area, or prohibited area. Examples include runway holding position signs (e.g., "15-33"), ILS critical area signs ("ILS"), and "NO ENTRY" signs. The runway designation is shown with the closer threshold listed first relative to the pilot's position (e.g., "15-33" when approaching from the side closer to runway 15).
• Location signs — Black background with yellow inscription and a yellow border. Identify the taxiway or runway on which the aircraft is located (e.g., a "B" identifies taxiway Bravo). Runway location signs (yellow runway number on black) indicate the runway you are currently on.
• Direction signs — Yellow background with black inscription and a black arrow. Identify the designations of intersecting taxiways leading out of the intersection. Inscriptions are arranged clockwise relative to the direction of travel.
• Destination signs — Yellow background with black inscription and arrow. Provide directional information to remote locations such as runways, terminals, civil aviation areas, or fuel facilities (e.g., "FUEL→").
• Information signs — Yellow background with black inscription. Provide pilot information regarding noise abatement procedures, radio frequencies, applicable regulations, etc. The airport operator determines the need.
• Runway distance remaining signs — Black background with white numeral. Indicate the remaining runway in thousands of feet (e.g., "3" = 3,000 ft remaining).

Practical Application

Before taxiing, a pilot should study the airport diagram and identify hot spots, complex intersections, and runway crossings along the expected taxi route. While taxiing:

1. Keep eyes outside; verify each sign as it is passed.
2. At every holding position marking, confirm clearance before crossing.
3. Use a sterile cockpit during taxi — no non-essential conversation.
4. If unsure of position, stop and ask ground control "verify position" rather than guessing.

Misinterpreting a single sign or marking is one of the most common causes of runway incursions, which is why correct identification of these visual aids is a frequent oral and practical test item.