Taxiway Markings and Signs
Taxiway direction signs have a yellow background and black characters, which identifies the designation or intersecting taxiways. Arrows indicate the direction of turn that would place the aircraft on the designated taxiway. [Figure 14-18] Direction signs are normally located on the left side of the taxiway and prior to the intersection. These signs and markings (with a yellow background and black characters) indicate the direction toward a different taxiway, leading off a runway, or out of an intersection. Figure 14-18 shows Taxiway Delta and how Taxiway Bravo intersects ahead at 90° both left and right.
Taxiway direction signs can also be displayed as surface painted markings. Figure 14-19 shows Taxiway Bravo as proceeding straight ahead while Taxiway Alpha turns to the right at approximately 45°.
Figure 14-20A and B shows an example of a direction sign at a complex taxiway intersection. Figure 14-20A and B shows Taxiway Bravo intersects with Taxiway Sierra at 90°, but at 45° with Taxiway Foxtrot. This type of array can be displayed with or without the taxiway location sign, which in this case would be Taxiway Bravo.
Enhanced Taxiway Centerline Markings
At most towered airports, the enhanced taxiway centerline marking is used to warn you of an upcoming runway. It consists of yellow dashed lines on either side of the normal solid taxiway centerline and the dashes extend up to 150 feet prior to a runway holding position marking. [Figure 14-21A and B] They are used to aid you in maintaining awareness during surface movement to reduce runway incursions.
Destination signs have black characters on a yellow background indicating a destination at the airport. These signs always have an arrow showing the direction of the taxi route to that destination. [Figure 14-22] When the arrow on the destination sign indicates a turn, the sign is located prior to the intersection. Destinations commonly shown on these types of signs include runways, aprons, terminals, military areas, civil aviation areas, cargo areas, international areas, and fixed-base operators. When the inscription for two or more destinations having a common taxi route are placed on a sign, the destinations are separated by a “dot” (•) and one arrow would be used as shown in Figure 14-22. When the inscription on a sign contains two or more destinations having different taxi routes, each destination is accompanied by an arrow and separated from the other destination(s) on the sign with a vertical black message divider as shown in Figure 14-23. The example shown in Figure 14-23 shows two signs. The sign in the foreground explains that Runway 20 threshold is to the left, and Runways 32, 2, and 14 are to the right. The sign in the background indicates that you are located on Taxiway Bravo and Taxiway November will take you to those runways.
Holding Position Signs and Markings for an Instrument Landing System (ILS) Critical Area
The instrument landing system (ILS) broadcasts signals to arriving instrument aircraft to guide them to the runway. Each of these ILSs have critical areas that must be kept clear of all obstacles in order to ensure quality of the broadcast signal. At many airports, taxiways extend into the ILS critical area. Most of the time, this is of no concern; however, during times of poor weather, an aircraft on approach may depend on a good signal quality. When necessary, ATC will protect the ILS critical area for arrival instrument traffic by instructing taxiing aircraft to “hold short” of Runway (XX) ILS critical area.
The ILS critical area hold sign has white characters, outlined in black, on a red background and is installed adjacent to the ILS holding position markings. [Figure 14-24] The holding position markings for the ILS critical area appear on the pavement as a horizontal yellow ladder extending across the width of the taxiway.
When instructed to “hold short of Runway (XX) ILS critical area,” you must ensure no portion of the aircraft extends beyond these markings. [Figure 14-25] If ATC does not instruct you to hold at this point, then you may bypass the ILS critical area hold position markings and continue with your taxi. Figure 14-24 shows that the ILS hold sign is located on Taxiway Golf and the ILS ladder hold position marking is adjacent to the hold sign.
Holding Position Markings for Taxiway/Taxiway Intersections
Holding position markings for taxiway/taxiway intersections consist of a single dashed yellow line extending across the width of the taxiway. [Figure 14-26] They are painted on taxiways where ATC normally holds aircraft short of a taxiway intersection. When instructed by ATC “hold short of Taxiway X,” you should stop so that no part of your aircraft extends beyond the holding position marking. When the marking is not present, you should stop your aircraft at a point that provides adequate clearance from an aircraft on the intersecting taxiway.
Marking and Lighting of Permanently Closed Runways and Taxiways
For runways and taxiways that are permanently closed, the lighting circuits are disconnected. The runway threshold, runway designation, and touchdown markings are obliterated and yellow “Xs” are placed at each end of the runway and at 1,000-foot intervals.
Temporarily Closed Runways and Taxiways
For temporarily closed runways and taxiways, a visual indication is often provided with yellow “Xs” or raised lighted yellow “Xs” placed at each end of the runway. Depending on the reason for the closure, duration of closure, airfield configuration, and the existence and the hours of operation of an ATC tower, a visual indication may not be present. As discussed previously in the chapter, you must always check NOTAMs and ATIS for runway and taxiway closure information.
Figure 14-27A shows an example of a yellow “X” laid flat with an adequate number of heavy sand bags to keep the wind from getting under and displacing the vinyl material.
A very effective and preferable visual aid to depict temporary closure is the lighted “X” placed on or near the runway designation numbers. [Figure 14-27B and C] This device is much more discernible to approaching aircraft than the other materials described above.
Some other markings found on the airport include vehicle roadway markings, VOR receiver checkpoint markings, and non-movement area boundary markings.
There are six types of signs that may be found at airports. The more complex the layout of an airport, the more important the signs become to pilots. The six types of signs are:
- Mandatory instruction signs—red background with white inscription. These signs denote an entrance to a runway, critical area, or prohibited area.
- Location signs—black with yellow inscription and a yellow border, no arrows. They are used to identify a taxiway or runway location, to identify the boundary of the runway, or identify an instrument landing system (ILS) critical area.
- Direction signs—yellow background with black inscription. The inscription identifies the designation of the intersecting taxiway(s) leading out of an intersection.
- Destination signs—yellow background with black inscription and arrows. These signs provide information on locating areas, such as runways, terminals, cargo areas, and civil aviation areas.
- Information signs—yellow background with black inscription. These signs are used to provide the pilot with information on areas that cannot be seen from the control tower, applicable radio frequencies, and noise abatement procedures. The airport operator determines the need, size, and location of these signs.
- Runway distance remaining signs—black background with white numbers. The numbers indicate the distance of the remaining runway in thousands of feet.