9.5 Airport Markings, Signs & Lighting
Key Takeaways
- Runway holding position markings are four yellow lines, two solid and two dashed; aircraft hold on the solid-line side until cleared to cross (AIM 2-3-5).
- Military airport beacons alternate white and green but show two quick white flashes between the green flashes, unlike civil land airports (AIM 2-1-9).
- Runway centerline lights are white until the last 3,000 feet, alternate red and white for 2,000 feet, and are all red for the final 1,000 feet (AIM 2-1-5).
- A VASI gives safe obstruction clearance within 10° of the extended centerline to 4 NM; a PAPI provides it within 10° to 3.4 NM (AIM 2-1-2).
- A destination sign has a yellow background, black inscription, and an arrow showing the taxi route to a destination such as a runway or the ramp (AIM 2-3-11).
Airport Markings, Signs & Lighting
The private and recreational knowledge areas include using the Aeronautical Information Manual and safe and efficient operation of aircraft (61.105(b)(3), (b)(7)), and the FAA's AGI sample questions test airport markings, signs, and lights directly. They are also a leading factor in runway incursions, so ground instructors should teach them precisely. The source for everything below is Chapter 2 of the Aeronautical Information Manual (AIM).
Runway Markings (White)
Runway markings are white. Depending on the runway's instrument status, they include:
- Runway designator: the magnetic heading rounded to the nearest 10° with the last zero dropped (Runway 27), with L, C, or R for parallel runways.
- Centerline: a line of uniformly spaced white stripes and gaps.
- Threshold markings: longitudinal stripes that identify the beginning of the runway available for landing.
- Aiming point marking: two broad white stripes, normally about 1,000 feet from the threshold, that serve as a visual aiming point.
- Touchdown zone markings: pairs of rectangular bars in 500-foot increments on precision runways.
- Side stripes: runway edges on precision runways.
Displaced Thresholds, Blast Pads & Closed Runways
| Marking | Meaning |
|---|---|
| Displaced threshold (white arrows leading to a white threshold bar) | The paved area before the threshold may be used for taxiing, takeoff, and the landing rollout from the opposite direction, but not for landing in that direction. |
| Blast pad or stopway (yellow chevrons) | Not available for taxiing, takeoff, or landing. |
| Closed runway or taxiway (yellow X) | Closed to all operations. |
Taxiway & Holding Position Markings (Yellow)
Taxiway markings are yellow. The taxiway centerline is a single continuous yellow line. A continuous double yellow edge line marks pavement not intended for aircraft; dashed edge lines mark pavement that may be used.
Runway holding position markings are the most important markings on the airport: four yellow lines, two solid and two dashed, across the taxiway. The solid lines are always on the side where the aircraft must hold. Approaching a runway, the pilot stops before the solid lines until ATC clears the aircraft onto or across the runway. Exiting a runway, the pilot crosses from the dashed side and is not clear of the runway until the entire aircraft has passed the marking. Two related markings:
- Enhanced taxiway centerline: dashed yellow lines on both sides of the centerline for up to 150 feet before a holding position marking, warning of an upcoming runway.
- ILS critical area holding position marking: two yellow solid lines joined by pairs of solid lines (a "ladder"), where ATC may hold aircraft to protect the ILS signal.
The non-movement area boundary is a solid and a dashed yellow line; the solid line is on the non-movement (ramp) side, where ATC clearance is not required.
The Six Airport Sign Types
| Sign Type | Colors | Examples and Meaning |
|---|---|---|
| Mandatory instruction | Red background, white inscription | Runway holding position sign ("15-33"), ILS critical area holding position sign, runway approach area holding position sign, and the NO ENTRY sign. Do not proceed past without an ATC clearance (or, at a non-towered airport, without ensuring the runway is clear). |
| Location | Black background, yellow inscription and border | Taxiway location sign ("B") or runway location sign tells you where you are. |
| Boundary (a location sign type) | Yellow background, black graphic | The runway boundary sign and the ILS critical area boundary sign face aircraft leaving the area; the ILS critical area boundary sign identifies the exit boundary of the ILS critical area. |
| Direction | Yellow background, black inscription with arrows | Shows the designations and directions of intersecting taxiways. |
| Destination | Yellow background, black inscription, always with an arrow | Shows the direction of the taxi route to a destination on the airport, such as a runway, the ramp, FBO, or cargo area. |
| Information | Yellow background, black inscription | Noise abatement, radio frequencies, and other local information. |
Runway distance remaining signs (black background, white numeral) show the remaining runway length in thousands of feet.
Airport Lighting
Airport Rotating Beacons
| Beacon Colors | Airport Type |
|---|---|
| White and green | Lighted civil land airport |
| White and green with two quick white flashes between the green flashes | Military airport |
| White and yellow | Lighted water airport |
| Green, yellow, and white | Lighted heliport |
In Class B, C, D, and E surface areas, operation of the beacon during daylight often indicates that ground visibility is below 3 miles and/or the ceiling is below 1,000 feet, but the AIM warns pilots not to rely on it; check the weather.
Visual Glide Path Indicators
- VASI: A two-bar VASI shows red over white when on the glide path ("red over white, you're all right"), white over white when high, and red over red when low. It provides safe obstruction clearance within ±10° of the extended runway centerline and out to 4 NM from the threshold. Do not start the descent until aligned with the runway.
- PAPI: A single row of two or four lights. With four lights, two white and two red means on the glide path (typically 3°), three white and one red means slightly high, four white means high, one white and three red slightly low, and four red low. Obstruction clearance is typically within ±10° and out to 3.4 NM.
Runway, Taxiway & Pilot-Controlled Lighting
- Runway edge lights are white. On instrument runways, yellow replaces white on the last 2,000 feet or half the runway length, whichever is less, forming a caution zone.
- Runway end lights show green outward to landing aircraft (the threshold) and red toward the runway for departing aircraft.
- Runway centerline lights are white until the last 3,000 feet, then alternate red and white for the next 2,000 feet, and are all red for the final 1,000 feet. A series of continuous red centerline lights therefore means 1,000 feet or less remains.
- Runway end identifier lights (REIL): a pair of synchronized flashing white lights at the threshold.
- Taxiway edge lights are blue; taxiway centerline lights are green.
- Runway guard lights (flashing yellow) and stop bars (red) mark runway holding positions.
- Pilot-controlled lighting: keying the microphone seven times within 5 seconds selects the highest intensity available, five times medium or lower, and three times the lowest intensity (AIM 2-1-8). Each keying sequence restarts the timer, typically 15 minutes.
Teaching Tip
Many runway incursions start with a pilot who misreads a holding position marking or confuses a location sign with a mandatory sign. Have students draw the holding position marking from memory, identify which side is solid, and state what the red and black signs mean before their first solo at a towered airport.
A pilot rolling out after landing at night sees that the runway centerline lights have changed from alternating red and white to continuous red. What does this indicate?
How can a military airfield be identified at night?
A pilot taxiing toward a runway reaches a runway holding position marking. Which statement is correct?
What does a destination sign identify?