14-1

Introduction

Each time a pilot operates an aircraft, the flight normally 

begins and ends at an airport. An airport may be a small sod 

field or a large complex utilized by air carriers. This chapter 

examines airport operations, identifies features of an airport 

complex, and provides information on operating on or in the 

vicinity of an airport.

Airport Categories

The definition for airports refers to any area of land or water 

used or intended for landing or takeoff of aircraft. This 

includes, within the five categories of airports listed below, 

special types of facilities including seaplane bases, heliports, 

and facilities to accommodate tilt rotor aircraft. An airport 

includes an area used or intended for airport buildings, 

facilities, as well as rights of way together with the buildings 

and facilities.

Airport 

Operations

Chapter 14
14-2

The law defines airports by categories of airport activities, 

including commercial service, primary, cargo service, 

reliever, and general aviation airports, as shown below:

• Commercial Service Airports—publicly owned 

airports that have at least 2,500 passenger boardings 

each calendar year and receive scheduled passenger 

service. Passenger boardings refer to revenue passenger 

boardings on an aircraft in service in air commerce 

whether or not in scheduled service. The definition 

also includes passengers who continue on an aircraft 

in international flight that stops at an airport in any of 

the 50 States for a non-traffic purpose, such as refueling 

or aircraft maintenance rather than passenger activity. 

Passenger boardings at airports that receive scheduled 

passenger service are also referred to as Enplanements.

• Cargo Service Airports—airports that, in addition to any 

other air transportation services that may be available, 

are served by aircraft providing air transportation of 

only cargo with a total annual landed weight of more 

than 100 million pounds. “Landed weight” means the 

weight of aircraft transporting only cargo in intrastate, 

interstate, and foreign air transportation. An airport 

may be both a commercial service and a cargo service 

airport.

• Reliever Airports—airports designated by the FAA 

to relieve congestion at Commercial Service Airports 

and to provide improved general aviation access to the 

overall community. These may be publicly or privatelyowned.

• General Aviation Airports — the remaining airports 

are commonly described as General Aviation Airports. 

This airport type is the largest single group of airports 

in the U.S. system. The category also includes privately 

owned, public use airports that enplane 2500 or more 

passengers annually and receive scheduled airline 

service. 

Types of Airports

There are two types of airports—towered and nontowered. 

These types can be further subdivided to:

• Civil Airports—airports that are open to the general 

public.

• Military/Federal Government airports—airports 

operated by the military, National Aeronautics and 

Space Administration (NASA), or other agencies of 

the Federal Government.

• Private Airports—airports designated for private or 

restricted use only, not open to the general public. 

Towered Airport

A towered airport has an operating control tower. Air traffic 

control (ATC) is responsible for providing the safe, orderly, 

and expeditious flow of air traffic at airports where the 

type of operations and/or volume of traffic requires such a 

service. Pilots operating from a towered airport are required 

to maintain two-way radio communication with ATC and to 

acknowledge and comply with their instructions. Pilots must 

advise ATC if they cannot comply with the instructions issued 

and request amended instructions. A pilot may deviate from 

an air traffic instruction in an emergency, but must advise 

ATC of the deviation as soon as possible.

Nontowered Airport

A nontowered airport does not have an operating control 

tower. Two-way radio communications are not required, 

although it is a good operating practice for pilots to transmit 

their intentions on the specified frequency for the benefit 

of other traffic in the area. The key to communicating at an 

airport without an operating control tower is selection of the 

correct common frequency. The acronym CTAF, which stands 

for Common Traffic Advisory Frequency, is synonymous 

with this program. A CTAF is a frequency designated for 

the purpose of carrying out airport advisory practices while 

operating to or from an airport without an operating control 

tower. The CTAF may be a Universal Integrated Community 

(UNICOM), MULTICOM, Flight Service Station (FSS), or 

tower frequency and is identified in appropriate aeronautical 

publications. UNICOM is a nongovernment air/ground radio 

communication station that may provide airport information 

at public use airports where there is no tower or FSS. On pilot 

request, UNICOM stations may provide pilots with weather 

information, wind direction, the recommended runway, or 

other necessary information. If the UNICOM frequency 

is designated as the CTAF, it is identified in appropriate 

aeronautical publications. Figure 14-1 lists recommended 

communication procedures. More information regarding 

radio communications is provided later in this chapter.

Nontowered airport traffic patterns are always entered at 

pattern altitude. How you enter the pattern depends upon the 

direction of arrival. The preferred method for entering from 

the downwind side of the pattern is to approach the pattern 

on a course 45 degrees to the downwind leg and join the 

pattern at midfield. 

There are several ways to enter the pattern if you’re coming 

from the upwind leg side of the airport. One method of entry 

from the opposite side of the pattern is to announce your 

intentions and cross over midfield at least 500 feet above 
14-3

UNICOM

(no tower or FSS)

No tower, FSS,

or UNICOM

No tower in 

operation, FSS open

FSS closed

(no tower)

Tower or FSS

not in operation

Communicate with UNICOM 

station on published CTAF 

frequency (122.7, 122.8, 122.725, 

122.975, or 123.0). If unable to 

contact UNICOM station, use selfannounce procedures on CTAF.

Self-announce on MULTICOM 

frequency 122.9.

Communicate with FSS on CTAF 

frequency.

Self-announce on CTAF.

Self-announce on CTAF.

Before taxiing and

before taxiing on the

runway for departure.

Before taxiing and

before taxiing on the

runway for departure.

Before taxiing and

before taxiing on the

runway for departure.

Before taxiing and

before taxiing on the

runway for departure.

Before taxiing and

before taxiing on the

runway for departure.

10 miles out.

Entering downwind,

base, and final.

Leaving the runway.

10 miles out.

Entering downwind,

base, and final.

Leaving the runway.

10 miles out.

Entering downwind,

base, and final.

Leaving the runway.

10 miles out.

Entering downwind,

base, and final.

Leaving the runway.

10 miles out.

Entering downwind,

base, and final.

Leaving the runway.

Facility at Airport Frequency Use

Communication/Broadcast Procedures

Departing final

approach fix (name) 

or on final approach

segment inbound.

Approach

completed/terminated.

Practice Instrument

Approach Outbound Inbound

Figure 14-1. Recommended communication procedures.

pattern altitude (normally 1,500 feet AGL.) However, if large or 

turbine aircraft operate at your airport, it is best to remain 2,000 

feet AGL so you are not in conflict with their traffic pattern. 

When well clear of the pattern—approximately 2 miles–scan 

carefully for traffic, descend to pattern altitude, then turn right 

to enter at 45° to the downwind leg at midfield. [Figure 14-2]

An alternate method is to enter on a midfield crosswind at 

pattern altitude, carefully scan for traffic, announce your 

intentions, and then turn downwind. [Figure 14-3] This 

technique should not be used if the pattern is busy. Always 

remember to give way to aircraft on the preferred 45° entry 

and to aircraft already established on downwind. 

In either case, it is vital to announce your intentions, and 

remember to scan outside. Before joining the downwind 

leg, adjust your course or speed to blend into the traffic. 

Adjust power on the downwind leg, or sooner, to fit into 

the flow of traffic. Avoid flying too fast or too slow. Speeds 

recommended by the airplane manufacturer should be used. 

They will generally fall between 70 to 80 knots for fixed-gear 

singles and 80 to 90 knots for high-performance retractable.

Sources for Airport Data

When a pilot flies into a different airport, it is important to 

review the current data for that airport. This data provides the 

pilot with information, such as communication frequencies, 

services available, closed runways, or airport construction. 

Three common sources of information are:

• Aeronautical Charts

• Chart Supplement U.S. (formerly Airport/Facility 

Directory)

• Notices to Airmen (NOTAMs)

• Automated Terminal Information Service (ATIS) 

Aeronautical Charts

Aeronautical charts provide specific information on airports. 

Chapter 16, “Navigation,” contains an excerpt from an 

aeronautical chart and an aeronautical chart legend, which 

provides guidance on interpreting the information on the chart.

Chart Supplement U.S. (formerly Airport/Facility 

Directory)

The Chart Supplement U.S. (formerly Airport/Facility 

Directory) provides the most comprehensive information on 

a given airport. It contains information on airports, heliports, 

and seaplane bases that are open to the public. The Chart 

Supplement U.S. is published in seven books, which are 

organized by regions and are revised every 56 days. The 

Chart Supplement U.S. is also available digitally at www.faa.
14-4

Figure 14-4. Chart Supplement U.S. (formerly Airport/Facility 

Directory excerpt.

Pattern altitude 

+500 feet

Descend to

pattern altitude,

then turn

Yield to 

downwind 

traffic and 

enter 

midfield 

downwind

at 45°

1

3

4

Fly clear of 

traffic pattern 

(approx. 2 mi.)

2

Figure 14-2. Preferred Entry-Crossing Midfield.

Yield to the preferred

45° and downwind

traffic, then turn

downwind

Pattern altitude

Figure 14-3. Alternate Midfield Entry.

gov/air_traffic/flight_info/aeronav. Figure 14-4 contains an 

excerpt from a directory. For a complete listing of information 

provided in a Chart Supplement U.S. and how the information 

may be decoded, refer to the “Legend Sample” located in the 

front of each Chart Supplement U.S.

In addition to airport information, each Chart Supplement 

U.S. contains information such as special notices, Federal 

Aviation Administration (FAA) and National Weather 

Service (NWS) telephone numbers, preferred instrument 

flight rules (IFR) routing, visual flight rules (VFR) waypoints, 

a listing of very high frequency (VHF) omnidirectional range 

(VOR) receiver checkpoints, aeronautical chart bulletins, land 

and hold short operations (LAHSO) for selected airports, 

airport diagrams for selected towered airports, en route 

flight advisory service (EFAS) outlets, parachute jumping 

areas, and facility telephone numbers. It is beneficial to 

review a Chart Supplement U.S. to become familiar with the 

information it contains.

Notices to Airmen (NOTAM)

Time-critical aeronautical information, which is of a temporary 

nature or not sufficiently known in advance to permit 

publication, on aeronautical charts or in other operational 
14-5

publications receives immediate dissemination by the 

NOTAM system. The NOTAM information could affect your 

decision to make the flight. It includes such information as 

taxiway and runway closures, construction, communications, 

changes in status of navigational aids, and other information 

essential to planned en route, terminal, or landing operations. 

Exercise good judgment and common sense by carefully 

regarding the information readily available in NOTAMs. 

Prior to any flight, pilots should check for any NOTAMs that 

could affect their intended flight. For more information on 

NOTAMs, refer back to Chapter 1, “Pilot and Aeronautical 

Information” section.

Automated Terminal Information Service (ATIS)

The Automated Terminal Information Service (ATIS) is a 

recording of the local weather conditions and other pertinent 

non-control information broadcast on a local frequency in a 

looped format. It is normally updated once per hour but is 

updated more often when changing local conditions warrant. 

Important information is broadcast on ATIS including 

weather, runways in use, specific ATC procedures, and any 

airport construction activity that could affect taxi planning.

When the ATIS is recorded, it is given a code. This code is 

changed with every ATIS update. For example, ATIS Alpha 

is replaced by ATIS Bravo. The next hour, ATIS Charlie is 

recorded, followed by ATIS Delta and progresses down the 

alphabet. 

Prior to calling ATC, tune to the ATIS frequency and listen to 

the recorded broadcast. The broadcast ends with a statement 

containing the ATIS code. For example, “Advise on initial 

contact, you have information Bravo.” Upon contacting the 

tower controller, state information Bravo was received. This 

allows the tower controller to verify the pilot has the current 

local weather and airport information without having to 

state it all to each pilot who calls. This also clears the tower 

frequency from being overtaken by the constant relay of 

the same information, which would result without an ATIS 

broadcast. The use of ATIS broadcasts at departure and arrival 

airports is not only a sound practice but a wise decision.

Airport Markings and Signs

There are markings and signs used at airports that provide 

directions and assist pilots in airport operations. It is important 

for you to know the meanings of the signs, markings, and lights 

that are used on airports as surface navigational aids. All airport 

markings are painted on the surface, whereas some signs are 

vertical and some are painted on the surface. An overview of the 

most common signs and markings are described on the following 

pages. Additional information may be found in Chapter 2, 

“Aeronautical Lighting and Other Airport Visual Aids,” of 

the Aeronautical Information Manual (AIM).

Runway Markings and Signs

Runway markings vary depending on the type of operations 

conducted at the airport. A basic VFR runway may only 

have centerline markings and runway numbers. Refer to 

Appendix C of this publication for an example of the most 

common runway markings that are found at airports.

Since aircraft are affected by the wind during takeoffs and 

landings, runways are laid out according to the local prevailing 

winds. Runway numbers are in reference to magnetic north. 

Certain airports have two or even three runways laid out in the 

same direction. These are referred to as parallel runways and 

are distinguished by a letter added to the runway number (e.g., 

runway 36L (left), 36C (center), and 36R (right)).

Relocated Runway Threshold

It is sometimes necessary, due to construction or runway 

maintenance, to close only a portion of a runway. When 

a portion of a runway is closed, the runway threshold is 

relocated as necessary. It is referred to as a relocated threshold 

and methods for identifying the relocated threshold vary. A 

common way for the relocated threshold to be marked is 

a ten foot wide white bar across the width of the runway. 

[Figure 14-5A and B]

When the threshold is relocated, the closed portion of the 

runway is not available for use by aircraft for takeoff or 

landing, but it is available for taxi. When a threshold is 

relocated, it closes not only a set portion of the approach 

end of a runway, but also shortens the length of the opposite 

direction runway. Yellow arrow heads are placed across the 

width of the runway just prior to the threshold bar.

Displaced Threshold

A displaced threshold is a threshold located at a point on 

the runway other than the designated beginning of the 

runway. Displacement of a threshold reduces the length 

of runway available for landings. The portion of runway 

behind a displaced threshold is available for takeoffs in either 

direction, or landings from the opposite direction. A ten feet 

wide white threshold bar is located across the width of the 

runway at the displaced threshold, and white arrows are 

located along the centerline in the area between the beginning 

of the runway and displaced threshold. White arrow heads 

are located across the width of the runway just prior to the 

threshold bar. [Figure 14-6A and B]
14-6

A B

36

Figure 14-5. (A) Relocated runway threshold drawing. (B) Relocated threshold for Runway 36 at Joplin Regional Airport (JLN).

Runway Safety Area 

The runway safety area (RSA) is a defined surface 

surrounding the runway prepared, or suitable, for reducing 

the risk of damage to airplanes in the event of an undershoot, 

overshoot, or excursion from the runway. The dimensions 

of the RSA vary and can be determined by using the 

criteria contained within AC 150/5300-13, Airport Design, 

Chapter 3. Figure 3-1 in AC 150/5300-13 depicts the RSA. 

Additionally, it provides greater accessibility for firefighting 

and rescue equipment in emergency situations. 

The RSA is typically graded and mowed. The lateral 

boundaries are usually identified by the presence of the 

runway holding position signs and markings on the adjoining 

taxiway stubs. Aircraft should not enter the RSA without 

making sure of adequate separation from other aircraft during 

operations at uncontrolled airports. [Figure 14-7]

Runway Safety Area Boundary Sign

Some taxiway stubs also have a runway safety area boundary 

sign that faces the runway and is visible to you only when 

exiting the runway. This sign has a yellow background with 

black markings and is typically used at towered airports 

where a controller commonly requests you to report clear of 

a runway. This sign is intended to provide you with another 

visual cue that is used as a guide to determine when you are 

clear of the runway safety boundary area. The sign shown in 

Figure 14-8 is what you would see when exiting the runway at 

Taxiway Kilo. You are out of the runway safety area boundary 

when the entire aircraft passes the sign and the accompanying 

surface painted marking.

Runway Holding Position Sign

Noncompliance with a runway holding position sign may 

result in the FAA filing a Pilot Deviation against you. A 
14-7

A

17

×

×

B

Figure 14-6. (A) Displaced runway threshold drawing. (B) Displaced threshold for Runway 17 at Albuquerque International Airport (ABQ). 27

9

A 9 B 27

9 C

Typical Runway Safety Area 

Figure 14-7. Runway Safety Area.

Figure 14-9. Runway holding position sign at takeoff end of Runway 

14 with collocated Taxiway Alpha location sign.

Figure 14-8. Runway safety area boundary sign and marking located 

on Taxiway Kilo.

runway holding position sign is an airport version of a 

stop sign. [Figure 14-9] It may be seen as a sign and/or its 

characters painted on the airport pavement. The sign has 

white characters outlined in black on a red background. It is 

always collocated with the surface painted holding position 

markings and is located where taxiways intersect runways. 

On taxiways that intersect the threshold of the takeoff runway, 

only the designation of the runway may appear on the sign. 

If a taxiway intersects a runway somewhere other than at 

the threshold, the sign has the designation of the intersecting 

runway. The runway numbers on the sign are arranged to 

correspond to the relative location of the respective runway 

thresholds. Figure 14-10 shows “18-36” to indicate the 

threshold for Runway 18 is to the left and the threshold for 
14-8

Figure 14-10. Runway holding position sign at a location other 

than the takeoff end of Runway 18-36 with collocated Taxiway 

Alpha location sign.

Runway 36 is to the right. The sign also indicates that you 

are located on Taxiway Alpha.

If the runway holding position sign is located on a taxiway 

at the intersection of two runways, the designations for 

both runways are shown on the sign along with arrows 

showing the approximate alignment of each runway. 

[Figure 14-11A and B] In addition to showing the 

approximate runway alignment, the arrows indicate the 

direction(s) to the threshold of the runway whose designation 

is immediately next to each corresponding arrow.

This type of taxiway and runway/runway intersection 

geometry can be very confusing and create navigational 

challenges. Extreme caution must be exercised when taxiing 

onto or crossing this type of intersection. Figure 14-11A and 

B shows a depiction of a taxiway, runway/runway intersection 

and is also designated as a “hot spot” on the airport diagram. 

In the example, Taxiway Bravo intersects with two runways, 

31-13 and 35-17, which cross each other.

Surface painted runway holding position signs may also be 

used to aid you in determining the holding position. These 

markings consist of white characters on a red background 

and are painted on the left side of the taxiway centerline. 

Figure 14-12 shows a surface painted runway holding 

position sign that is the holding point for Runway 32R-14L. 

You should never allow any part of your aircraft to cross the 

runway holding position sign (either a vertical or surface 

painted sign) without a clearance from ATC. Doing so poses 

a hazard to yourself and others. 

When the tower is closed or you are operating at a nontowered 

airport, you may taxi past a runway holding position sign only 

when the runway is clear of aircraft, and there are no aircraft on 

final approach. You may then proceed with extreme caution.

Runway Holding Position Marking

Noncompliance with a runway holding position marking 

may result in the FAA filing a Pilot Deviation against you.

Runway holding position markings consist of four yellow 

lines, two solid and two dashed, that are painted on the surface 

and extend across the width of the taxiway to indicate where 

the aircraft should stop when approaching a runway. These 

markings are painted across the entire taxiway pavement, are 

in alignment, and are collocated with the holding position 

sign as described above. 

As you approach the runway, two solid yellow lines and two 

dashed lines will be visible. Prior to reaching the solid lines, it 

is imperative to stop and ensure that no portion of the aircraft 

intersects the first solid yellow line. Do not cross the double 

solid lines until a clearance from ATC has been received. 

[Figure 14-13] When the tower is closed or when operating at 

a nontowered airport, you may taxi onto or across the runway 

only when the runway is clear and there are no aircraft on final 

approach. You should use extreme caution when crossing or 

taxiing onto the runway and always look both ways.

When exiting the runway, the same markings will be seen 

except the aircraft will be approaching the double dashed 

lines. [Figure 14-14] In order to be clear of the runway, the 

entire aircraft must cross both the dashed and solid lines. 

An ATC clearance is not needed to cross this marking when 

exiting the runway. 

Runway Distance Remaining Signs

Runway distance remaining signs have a black background 

with a white number and may be installed along one or both 

sides of the runway. [Figure 14-15] The number on the 

signs indicates the distance, in thousands of feet, of landing 

runway remaining. The last sign, which has the numeral “1,” 

is located at least 950 feet from the runway end.

Runway Designation Marking

Runway numbers and letters are determined from the 

approach direction. The runway number is the whole number 

nearest one-tenth the magnetic azimuth of the centerline of the 

runway, measured clockwise from the magnetic north. In the 

case where there are parallel runways, the letters differentiate 

between left (L), right (R), or center (C). [Figure 14-16] For 

example, if there are two parallel runways, they would show 

the designation number and then either L or R beneath it. 

For three parallel runways, the designation number would 

be presented with L, C, or R beneath it. 
14-9

NC-3, 08 MAR 2012 ot 05 APR 2012

NC-3, 08 MAR 2012 to 05 APR 2012

Not to be used for navigation

35 35-17

31-13

B 31-13 35-17

A

B

Runway 13

Runway 31

Figure 14-11. (A) Taxiway Bravo location sign collocated with runway/runway intersection holding signs at Sioux Gateway Airport 

(SUX) (B) Airport diagram of Sioux Gateway Airport (SUX), Sioux City, Iowa. The area outlined in red is a designated “hot spot” (HS1).
14-10

Figure 14-12. Surface painted runway holding position signs for 

Runway 32R-14L along with the enhanced taxiway centerline marking.

Figure 14-13. Surface painted holding position marking along with 

enhanced taxiway centerline.

Figure 14-14. Runway holding position markings as seen when 

exiting the runway. When exiting the runway, no ATC clearance 

is required to cross.

Figure 14-15. Runway distance remaining sign indicating that there 

is 2,000 feet of runway remaining.

Land and Hold Short Operations (LAHSO)

When simultaneous operations (takeoffs and landings) are 

being conducted on intersecting runways, Land and Hold 

Short Operations (LAHSO) may also be in effect. LAHSO 

is an ATC procedure that may require your participation and 

compliance. As pilot in command (PIC), you have the final 

authority to accept or decline any LAHSO clearance.

If issued a land and hold short clearance, you must be aware 

of the reduced runway distances and whether or not you can 

comply before accepting the clearance. You do not have 

to accept a LAHSO clearance. Pilots should only receive a 

LAHSO clearance when there is a minimum ceiling of 1,000 

feet and 3 statute miles of visibility.

Runway holding position signs and markings are installed 

on those runways used for LAHSO. The signs and markings 

are placed at the LAHSO point to aid you in determining 

where to stop and hold the aircraft and are located prior to 

the runway/runway intersection. [Figure 14-17]

The holding position sign has a white inscription with black 

border around the numbers on a red background and is installed 

adjacent to the holding position markings. If you accept a land 

and hold short clearance, you must comply so that no portion 

of the aircraft extends beyond these hold markings.

If receiving “cleared to land” instructions from ATC, you 

are authorized to use the entire landing length of the runway 

and should disregard any LAHSO holding position markings 

located on the runway. If you receive and accept LAHSO 

instructions, you must stop short of the intersecting runway 

prior to the LAHSO signs and markings.

Below is a list of items which, if thoroughly understood 

and complied with, will ensure that LAHSO operations are 

conducted properly.

• Know landing distance available.

• Be advised by ATC as to why LAHSO are being 

conducted.
14-11

35

L

35

C

Figure 14-16. Two of three parallel runways.

Figure 14-17. Runway holding position sign and marking for LAHSO.

• Advise ATC if you cannot comply with LAHSO.

• Know what signs and markings are at the LAHSO point.

• LAHSO are not authorized for student pilots who are 

performing a solo flight.

• At many airports air carrier aircraft are not authorized 

to participate in LAHSO if the other aircraft is a 

general aviation aircraft.

• Generally, LAHSO are not authorized at night.

• LAHSO are not authorized on wet runways.

If you accept the following clearance from ATC: “Cleared to 

land Runway 36 hold short of Runway 23,” you must either exit 

Runway 36 or stop at the holding position prior to Runway 23.

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°.
14-12

Figure 14-18. Taxiway Bravo direction sign with a collocated 

Taxiway Delta location sign. When the arrow on the direction 

sign indicates a turn, the sign is located prior to the intersection.

Figure 14-19. Surface painted taxiway direction signs.

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

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. 
14-13

F

S S

B

F S F B S F

A

B

Figure 14-20. Orientation of signs is from left to right in a clockwise manner. Left turn signs are on the left and right turn on the right. 

In this view, the pilot is on Taxiway Bravo.

Enhanced taxiway centerline marking extends 150 feet prior 

to a runway holding position marking. Prepare to STOP.

Prepare to STOP unless you have been cleared onto 

or across the runway by ATC.

A

B

Figure 14-21. (A) Enhanced taxiway centerline marking. (B) Enhanced taxiway centerline marking and runway holding position marking.

Enhanced taxiway centerline marking extends 150 feet prior 

to a runway holding position marking. Prepare to STOP.

A

B
14-14

Figure 14-24. Instrument landing system (ILS) holding position sign 

and marking on Taxiway Golf. 

ILS Critical Area boundary

ILS

Hold only

when

specifically

instructed by ATC

19

The yellow surface 

painted “ladder” 

marking and red ILS 

sign are located 

on taxiways where 

the taxiways intersect 

the ILS critical area.

Figure 14-25. Holding position sign and marking for instrument 

landing system (ILS) critical area boundary.

Figure 14-22. Destination sign to the fixed-base operator (FBO).

Figure 14-23. Runway destination sign with different taxi routes. 

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.
14-15

A

C

B

Figure 14-27. (A) Yellow “X” placed on surface of temporarily closed 

runways. (B) Lighted “X” placed on temporarily closed runways. 

(C) Lighted “X” at night showing a temporarily closed runway.

G B

G

G

B

B G

B G

Figure 14-26. Holding position marking on a taxiway. 

• 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.

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.

Other Markings

Some other markings found on the airport include vehicle 

roadway markings, VOR receiver checkpoint markings, and 

non-movement area boundary markings.

Airport Signs

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. Appendix C of this publication 

shows examples of some signs that are found at most airports, 

their purpose, and appropriate pilot action. 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.
14-16

White Green White Yellow 

Figure 14-28. Airport rotating beacons.

• 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.

Airport Lighting

The majority of airports have some type of lighting for night 

operations. The variety and type of lighting systems depends 

on the volume and complexity of operations at a given airport. 

Airport lighting is standardized so that airports use the same 

light colors for runways and taxiways.

Airport Beacon

Airport beacons help a pilot identify an airport at night. 

The beacons are normally operated from dusk until dawn. 

Sometimes they are turned on if the ceiling is less than 1,000 

feet and/or the ground visibility is less than 3 statute miles (VFR 

minimums). However, there is no requirement for this, so a 

pilot has the responsibility of determining if the weather meets 

VFR requirements. The beacon has a vertical light distribution 

to make it most effective from 1–10° above the horizon, 

although it can be seen well above or below this spread. The 

beacon may be an omnidirectional capacitor-discharge device, 

or it may rotate at a constant speed, that produces the visual 

effect of flashes at regular intervals. The combination of light 

colors from an airport beacon indicates the type of airport. 

[Figure 14-28] Some of the most common beacons are:

• Flashing white and green for civilian land airports

• Flashing white and yellow for a water airport

• Flashing white, yellow, and green for a heliport

• Two quick white flashes alternating with a green flash 

identifying a military airport

Approach Light Systems

Approach light systems are primarily intended to provide a 

means to transition from instrument flight to visual flight for 

landing. The system configuration depends on whether the 

runway is a precision or nonprecision instrument runway. 

Some systems include sequenced flashing lights that appear 

to the pilot as a ball of light traveling toward the runway at 

high speed. Approach lights can also aid pilots operating 

under VFR at night.

Visual Glideslope Indicators

Visual glideslope indicators provide the pilot with glidepath 

information that can be used for day or night approaches. By 

maintaining the proper glidepath as provided by the system, 

a pilot should have adequate obstacle clearance and should 

touch down within a specified portion of the runway.

Visual Approach Slope Indicator (VASI)

VASI installations are the most common visual glidepath 

systems in use. The VASI provides obstruction clearance 

within 10° of the extended runway centerline and up to four 

nautical miles (NM) from the runway threshold.

The VASI consists of light units arranged in bars. There are 

2-bar and 3-bar VASIs. The 2-bar VASI has near and far light 

bars and the 3-bar VASI has near, middle, and far light bars. 

Two-bar VASI installations provide one visual glidepath 

that is normally set at 3°. The 3-bar system provides two 

glidepaths, the lower glidepath normally set at 3° and the 

upper glidepath 1⁄4 degree above the lower glidepath. 

The basic principle of the VASI is that of color differentiation 

between red and white. Each light unit projects a beam of 

light, a white segment in the upper part of the beam and a 

red segment in the lower part of the beam. The lights are 

arranged so the pilot sees the combination of lights shown in 

Figure 14-29 to indicate below, on, or above the glidepath.

Other Glidepath Systems

A precision approach path indicator (PAPI) uses lights similar 

to the VASI system, except they are installed in a single row, 

normally on the left side of the runway. [Figure 14-30]
14-17

Below Glidepath On Glidepath Above Glidepath

Far Bar

Near Bar

Far Bar

Near Bar

Far Bar

Near Bar

Figure 14-29. Two-bar VASI system.

High

more than 3.5°

Slightly High

 3.2°

On Glidepath

 3°

Slightly Low

 2.8°

Low

less than 2.5°

Figure 14-30. Precision approach path indicator for a typical 3° glide slope.

Below glidepath

Above glidepath

On glidepath

Amber

Red

Green

Amber

Figure 14-31. Tri-color visual approach slope indicator.

A tri-color system consists of a single-light unit projecting 

a three-color visual approach path. Below the glidepath is 

indicated by red, on the glidepath is indicated by green, and 

above the glidepath is indicated by amber. When descending 

below the glidepath, there is a small area of dark amber. Pilots 

should not mistake this area for an “above the glidepath” 

indication. [Figure 14-31] 

Pulsating VASIs normally consist of a single-light unit 

projecting a two-color visual approach path into the final 

approach area of the runway upon which the indicator is 

installed. The “on glidepath” indication is a steady white 

light. The “slightly below glidepath” indication is a steady red 

light. If the aircraft descends further below the glidepath, the 

red light starts to pulsate. The “above glidepath” indication 

is a pulsating white light. The pulsating rate increases as the 

aircraft gets further above or below the desired glideslope. 

The useful range of the system is about four miles during the 

day and up to ten miles at night. [Figure 14-32]

Runway Lighting

There are various lights that identify parts of the runway 

complex. These assist a pilot in safely making a takeoff or 

landing during night operations.

Runway End Identifier Lights (REIL)

Runway end identifier lights (REIL) are installed at many 

airfields to provide rapid and positive identification of the 

approach end of a particular runway. The system consists 

of a pair of synchronized flashing lights located laterally 

on each side of the runway threshold. REILs may be either 

omnidirectional or unidirectional facing the approach area.

Runway Edge Lights

Runway edge lights are used to outline the edges of 

runways at night or during low visibility conditions. 

[Figure 14-33] These lights are classified according to the 

intensity they are capable of producing: high intensity runway 

lights (HIRL), medium intensity runway lights (MIRL), and 
14-18

Below glidepath

Above glidepath

On glidepath

Pulsating white

Pulsating red

Steady

white

Threshold

Slightly below glidepath

Steady

red

Figure 14-32. Pulsating visual approach slope indicator.

Figure 14-33. Runway lights.

low intensity runway lights (LIRL). The HIRL and MIRL 

have variable intensity settings. These lights are white, except 

on instrument runways where amber lights are used on the 

last 2,000 feet or half the length of the runway, whichever 

is less. The lights marking the end of the runway are red.

In-Runway Lighting

Runway centerline lighting system (RCLS)—installed on some 

precision approach runways to facilitate landing under adverse 

visibility conditions. They are located along the runway 

centerline and are spaced at 50-foot intervals. When viewed 

from the landing threshold, the runway centerline lights are 

white until the last 3,000 feet of the runway. The white lights 

begin to alternate with red for the next 2,000 feet. For the 

remaining 1,000 feet of the runway, all centerline lights are red. 

Touchdown zone lights (TDZL)—installed on some precision 

approach runways to indicate the touchdown zone when 

landing under adverse visibility conditions. They consist of 

two rows of transverse light bars disposed symmetrically 

about the runway centerline. The system consists of steadyburning white lights that start 100 feet beyond the landing 

threshold and extend to 3,000 feet beyond the landing 

threshold or to the midpoint of the runway, whichever is less. 

Taxiway centerline lead-off lights—provide visual guidance 

to persons exiting the runway. They are color-coded to warn 

pilots and vehicle drivers that they are within the runway 

environment or ILS critical area, whichever is more restrictive. 

Alternate green and yellow lights are installed, beginning 

with green, from the runway centerline to one centerline light 

position beyond the runway holding position or ILS critical 

area holding position. 

Taxiway centerline lead-on lights—provide visual guidance 

to persons entering the runway. These “lead-on” lights are 

also color-coded with the same color pattern as lead-off 

lights to warn pilots and vehicle drivers that they are within 

the runway environment or ILS critical area, whichever is 

more conservative. The fixtures used for lead-on lights are 

bidirectional (i.e., one side emits light for the lead-on function 

while the other side emits light for the lead-off function). Any 

fixture that emits yellow light for the lead-off function also 

emits yellow light for the lead-on function. 

Land and hold short lights—used to indicate the hold short 

point on certain runways which are approved for LAHSO. 

Land and hold short lights consist of a row of pulsing white 

lights installed across the runway at the hold short point. 

Where installed, the lights are on anytime LAHSO is in effect. 

These lights are off when LAHSO is not in effect. 

Control of Airport Lighting

Airport lighting is controlled by ATC at towered airports. At 

nontowered airports, the lights may be on a timer, or where an 

FSS is located at an airport, the FSS personnel may control the 

lighting. A pilot may request various light systems be turned 

on or off and also request a specified intensity, if available, 

from ATC or FSS personnel. At selected nontowered airports, 

the pilot may control the lighting by using the radio. This 

is done by selecting a specified frequency and clicking the 

radio microphone. [Figure 14-34] For information on pilot 

controlled lighting at various airports, refer to the Chart 

Supplement U.S. (formerly Airport/Facility Directory).
14-19

Key Mike Function

Highest intensity available

Medium or lower intensity

(Lower REIL or REIL off)

Lowest intensity available

(Lower REIL or REIL off)

7 times within 5 seconds

5 times within 5 seconds

3 times within 5 seconds

Figure 14-34. Radio controlled runway lighting.

Taxiway Lights

Similar to runway lighting, taxiways also have various lights 

which help pilots identify areas of the taxiway and any 

surrounding runways. 

Omnidirectional 

Omnidirectional taxiway lights outline the edges of the 

taxiway and are blue in color. At many airports, these 

edge lights may have variable intensity settings that may 

be adjusted by an ATC when deemed necessary or when 

requested by the pilot. Some airports also have taxiway 

centerline lights that are green in color.

Clearance Bar Lights

Clearance bar lights are installed at holding positions on 

taxiways in order to increase the conspicuity of the holding 

position in low visibility conditions. They may also be 

installed to indicate the location of an intersecting taxiway 

during periods of darkness. Clearance bars consist of three 

in-pavement steady-burning yellow lights.

Runway Guard Lights

Runway guard lights are installed at taxiway/runway 

intersections. They are primarily used to enhance the 

conspicuity of taxiway/runway intersections during low 

visibility conditions, but may be used in all weather conditions. 

Runway guard lights consist of either a pair of elevated flashing 

yellow lights installed on either side of the taxiway, or a row of 

in-pavement yellow lights installed across the entire taxiway, 

at the runway holding position marking.

Note: Some airports may have a row of three or five 

in-pavement yellow lights installed at taxiway/runway 

intersections. They should not be confused with clearance 

bar lights described previously in this section. 

Stop Bar Lights

Stop bar lights, when installed, are used to confirm the ATC 

clearance to enter or cross the active runway in low visibility 

conditions (below 1,200 ft Runway Visual Range (RVR)). 

A stop bar consists of a row of red, unidirectional, steadyburning in-pavement lights installed across the entire taxiway 

at the runway holding position, and elevated steady-burning 

red lights on each side. A controlled stop bar is operated in 

conjunction with the taxiway centerline lead-on lights which 

extend from the stop bar toward the runway. Following the 

ATC clearance to proceed, the stop bar is turned off and the 

lead-on lights are turned on. The stop bar and lead-on lights 

are automatically reset by a sensor or backup timer.

Obstruction Lights

Obstructions are marked or lighted to warn pilots of 

their presence during daytime and nighttime conditions. 

Obstruction lighting can be found both on and off an airport 

to identify obstructions. They may be marked or lighted in 

any of the following conditions.

• Red obstruction lights—flash or emit a steady red 

color during nighttime operations, and the obstructions 

are painted orange and white for daytime operations.

• High intensity white obstruction lights—flash high 

intensity white lights during the daytime with the 

intensity reduced for nighttime.

• Dual lighting—a combination of flashing red beacons 

and steady red lights for nighttime operation and high 

intensity white lights for daytime operations.

New Lighting Technologies

A top priority of the FAA is to continue to enhance airport 

safety while maintaining airport capacity. Reducing runway 

incursions is a major component of this effort. Runway 

incursions develop quickly and without warning during routine 

traffic situations on the airport surface, leaving little time for 

corrective action. The Runway Status Lights (RWSL) System 

is designed to provide a direct indication to you that it is unsafe 

to enter a runway, cross a runway, or takeoff from or land on 

a runway when the system is activated. 

Runway status lights are red in color and indicate runway 

status only; they do not indicate clearance to enter a runway 

or clearance to takeoff. The RWSL system provides warning 

lights on runways and taxiways, illuminating when it is unsafe 

to enter, cross, or begin takeoff on a runway. Currently, there 

are two types: Runway Entrance Lights (REL) and Takeoff 

Hold Lights (THL). [Figures 14-35 and 14-36]

REL provide a warning to aircraft crossing or entering a 

runway from intersecting taxiways that there is conflicting 

traffic on the runway. THL provide a warning signal to 

aircraft in position for takeoff that the runway is occupied 

and it is unsafe to take off. As of 2016, the RWSL system is 

operational at 14 of the nation’s busiest airports with 3 more 

airports scheduled to receive the system by 2017.
14-20

Figure 14-35. Runway Entrance Lights (REL).

Figure 14-36. Takeoff Hold Lights (THL).

Wind Direction Indicators

It is important for a pilot to know the direction of the wind. At 

facilities with an operating control tower, this information is 

provided by ATC. Information may also be provided by FSS 

personnel either located at a particular airport or remotely 

available through a remote communication outlet (RCO), or 

by requesting information on a CTAF at airports that have the 

capacity to receive and broadcast on this frequency.

When none of these services is available, it is possible 

to determine wind direction and runway in use by visual 

wind indicators. A pilot should check these wind indicators 

even when information is provided on the CTAF at a given 

airport because there is no assurance that the information 

provided is accurate. 

The wind direction indicator can be a wind cone, wind sock, 

tetrahedron, or wind tee. These are usually located in a central 

location near the runway and may be placed in the center 

of a segmented circle, which identifies the traffic pattern 

direction if it is other than the standard left-hand pattern. 

[Figures 14-37 and 14-38] 

The wind sock is a good source of information since it not 

only indicates wind direction but allows the pilot to estimate 

the wind velocity and/or gust factor. The wind sock extends 

out straighter in strong winds and tends to move back and 

forth when the wind is gusting. Wind tees and tetrahedrons 

can swing freely and align themselves with the wind direction. 

Since a wind tee or tetrahedron can also be manually set to 

align with the runway in use, a pilot should also look at the 

wind sock for wind information, if one is available.

Traffic Patterns 

At airports without an operating control tower, a segmented 

circle visual indicator system, if installed, is designed to 

provide traffic pattern information. [Figure 14-38] Usually 

located in a position affording maximum visibility to pilots in 

the air and on the ground and providing a centralized location 

for other elements of the system, the segmented circle consists 

of the following components: wind direction indicators, 

landing direction indicators, landing strip indicators, and 

traffic pattern indicators.

A tetrahedron is installed to indicate the direction of landings 

and takeoffs when conditions at the airport warrant its use. 

It may be located at the center of a segmented circle and 

may be lighted for night operations. The small end of the 

tetrahedron points in the direction of landing. Pilots are 

cautioned against using a tetrahedron for any purpose other 

than as an indicator of landing direction. At airports with 

control towers, the tetrahedron should only be referenced 

when the control tower is not in operation. Tower instructions 

supersede tetrahedron indications.

Landing strip indicators are installed in pairs and are used to 

show the alignment of landing strips. [Figure 14-38] Traffic 

pattern indicators are arranged in pairs in conjunction with 

landing strip indicators and used to indicate the direction of 

turns when there is a variation from the normal left traffic 

pattern. (If there is no segmented circle installed at the airport, 

traffic pattern indicators may be installed on or near the end 

of the runway.) 

At most airports and military air bases, traffic pattern altitudes 

for propeller-driven aircraft generally extend from 600 feet 

to as high as 1,500 feet above ground level (AGL). Pilots 

can obtain the traffic pattern altitude for an airport from the

Chart Supplement U.S. (formerly Airport/Facility Directory). 

Also, traffic pattern altitudes for military turbojet aircraft 

sometimes extend up to 2,500 feet AGL. Therefore, pilots of 

en route aircraft should be constantly on alert for other aircraft 

in traffic patterns and avoid these areas whenever possible. 

When operating at an airport, traffic pattern altitudes should 

be maintained unless otherwise required by the applicable 

distance from cloud criteria according to Title 14 of the Code 

of Federal Regulations (14 CFR) part 91, section 91.155. 

Additional information on airport traffic pattern operations 
14-21

Tetrahedron

Wind sock or cone

Wind tee

WIND 

Figure 14-37. Wind direction indicators.

Landing runway Wind cone

or landing strip 

indicators

Landing direction

indicator

Traffic pattern

indicators

Figure 14-38. Segmented circle.

can be found in Chapter 4, “Air Traffic Control,” of the AIM. 

Pilots can find traffic pattern information and restrictions, such 

as noise abatement in the Chart Supplement U.S. (formerly 

Airport/Facility Directory).

Example: Key to Traffic Pattern Operations—

Single Runway

1. Enter pattern in level flight, abeam the midpoint 

of the runway, at pattern altitude. (1,000' AGL is 

recommended pattern altitude unless otherwise 

established.) [Figure 14-39]

2. Maintain pattern altitude until abeam approach end of 

the landing runway on downwind leg. [Figure 14-39]

3. Complete turn to final at least 1⁄4 mile from the runway. 

[Figure 14-39]

4. After takeoff or go-around, continue straight ahead 

until beyond departure end of runway. [Figure 14-39]

5. If remaining in the traffic pattern, commence turn to 

crosswind leg beyond the departure end of the runway 

within 300 feet of pattern altitude. [Figure 14-39]

6. If departing the traffic pattern, continue straight out, 

or exit with a 45° turn (to the left when in a left-hand 

traffic pattern; to the right when in a right-hand traffic 

pattern) beyond the departure end of the runway, after 

reaching pattern altitude. [Figure 14-39]

Example: Key to Traffic Pattern Operations—

Parallel Runways

1. Enter pattern in level flight, abeam the midpoint 

of the runway, at pattern altitude. (1,000' AGL is 

recommended pattern altitude unless otherwise 

established.) [Figure 14-40]

2. Maintain pattern altitude until abeam approach end of 

the landing runway on downwind leg. [Figure 14-40]

3. Complete turn to final at least 1⁄4 mile from the runway. 

[Figure 14-40]

4. Do not overshoot final or continue on a track that 

penetrates the final approach of the parallel runway 

5. After takeoff or go-around, continue straight ahead 

until beyond departure end of runway. [Figure 14-40]
14-22

LEGEND

Recommended standard left-hand traffic

pattern (depicted) (standard right-hand

traffic pattern would be mirror image)

RUNWAY

Final Departure

Downwind 

Base

Crosswind

Departure

Departure

Entry

Application of traffic

pattern indicators

Segmented circle

3

4 6

6

5

2

1

Figure 14-39. Traffic pattern operations—single runway.

6. If remaining in the traffic pattern, commence turn to 

crosswind leg beyond the departure end of the runway 

within 300 feet of pattern altitude. [Figure 14-40]

7. If departing the traffic pattern, continue straight out, 

or exit with a 45° turn (to the left when in a left-hand 

traffic pattern; to the right when in a right-hand traffic 

pattern) beyond the departure end of the runway, after 

reaching pattern altitude. [Figure 14-40]

8. Do not continue on a track that penetrates the departure 

path of the parallel runway. [Figure 14-40]

Radio Communications

Operating in and out of a towered airport, as well as in a good 

portion of the airspace system, requires that an aircraft have twoway radio communication capability. For this reason, a pilot 

should be knowledgeable of radio station license requirements 

and radio communications equipment and procedures.

Radio License

There is no license requirement for a pilot operating in the 

United States; however, a pilot who operates internationally 

is required to hold a restricted radiotelephone permit issued 

by the Federal Communications Commission (FCC). There 

is also no station license requirement for most general 

aviation aircraft operating in the United States. A station 

license is required, however, for an aircraft that is operating 

internationally, that uses other than a VHF radio, and that 

meets other criteria.

Radio Equipment

In general aviation, the most common types of radios are 

VHF. A VHF radio operates on frequencies between 118.0 

megahertz (MHz) and 136.975 MHz and is classified as 

720 or 760 depending on the number of channels it can 

accommodate. The 720 and 760 use .025 MHz (25 kilohertz 

(KHz) spacing (118.025, 118.050) with the 720 having a 

frequency range up to 135.975 MHz and the 760 reaching 

up to 136.975 MHz. VHF radios are limited to line of sight 

transmissions; therefore, aircraft at higher altitudes are able 

to transmit and receive at greater distances.

In March of 1997, the International Civil Aviation Organization 

(ICAO) amended its International Standards and Recommended 

Practices to incorporate a channel plan specifying 8.33 kHz 

channel spacings in the Aeronautical Mobile Service. The 

8.33 kHz channel plan was adopted to alleviate the shortage of 

VHF ATC channels experienced in western Europe and in the 

United Kingdom. Seven western European countries and the 

United Kingdom implemented the 8.33 kHz channel plan on 

January 1, 1999. Accordingly, aircraft operating in the airspace 

of these countries must have the capability of transmitting and 

receiving on the 8.33 kHz spaced channels.

Using Proper Radio Procedures 

Using proper radio phraseology and procedures contribute to 

a pilot’s ability to operate safely and efficiently in the airspace 

system. A review of the Pilot/Controller Glossary contained 

in the AIM assists a pilot in the use and understanding of 
14-23

Figure 14-40. Traffic pattern operation—parallel runways.

LEGEND

Standard left-hand 

traffic pattern (depicted)

Right-hand traffic

pattern (depicted)

Final Departure

Base 

Crosswind

Final Departure

Base 

Crosswind

Downwind 

Entry

No transgression zone Segmented circle No transgression zone

3 4

6

6

5

2

1

3

4 6

6

5

2

1

standard terminology. The AIM also contains many examples 

of radio communications.

ICAO has adopted a phonetic alphabet that should be used in 

radio communications. When communicating with ATC, pilots 

should use this alphabet to identify their aircraft. [Figure 14-41]

Lost Communication Procedures

It is possible that a pilot might experience a malfunction of 

the radio. This might cause the transmitter, receiver, or both 

to become inoperative. If a receiver becomes inoperative and a 

pilot needs to land at a towered airport, it is advisable to remain 

outside or above Class D airspace until the direction and flow 

of traffic is determined. A pilot should then advise the tower of 

the aircraft type, position, altitude, and intention to land. The 

pilot should continue, enter the pattern, report a position as 

appropriate, and watch for light signals from the tower. Light 

signal colors and their meanings are contained in Figure 14-42.

If the transmitter becomes inoperative, a pilot should follow 

the previously stated procedures and also monitor the 

appropriate ATC frequency. During daylight hours, ATC 

transmissions may be acknowledged by rocking the wings 

and at night by blinking the landing light.

When both receiver and transmitter are inoperative, the pilot 

should remain outside of Class D airspace until the flow of 

traffic has been determined and then enter the pattern and 

watch for light signals.

Radio malfunctions should be repaired before further 

flight. If this is not possible, ATC may be contacted by 

telephone requesting a VFR departure without two-way radio 

communications. No radio (NORDO) procedure arrivals 

are not accepted at busy airports. If authorization is given 

to depart, the pilot is advised to monitor the appropriate 

frequency and/or watch for light signals as appropriate.
14-24

Character Morse Code Telephony Phonic Pronunciation

r

R0

q Q9

p P8

o

O7

n N6

5 55

4 44

3 33

2 22

1 11

z

ZZ

y YY

x XX

WWw

v VV

u

UU

t TT

s SS

r

RR

q QQ

p PP

o

OO

n NN

MMm

L LL

k KK

j JJ

i II

h hH

GGg

f FF

e

EE

d DD

c

CC

b BB

a AA

Figure 14-41. Phonetic alphabet.

easily be aware of your presence when they are expecting 

the standard radio calls.

Air Traffic Control (ATC) Services

Besides the services provided by an FSS as discussed in 

Chapter 12, “Aviation Weather Services,” numerous other 

services are provided by ATC. In many instances a pilot 

is required to have contact with ATC, but even when not 

required, a pilot may find their services helpful.

Primary Radar

Radar is a device that provides information on range, azimuth, 

and/or elevation of objects in the path of the transmitted 

pulses. It measures the time interval between transmission and 

reception of radio pulses and correlates the angular orientation 

of the radiated antenna beam or beams in azimuth and/or 

elevation. Range is determined by measuring the time it takes 

for the radio wave to go out to the object and then return to the 

receiving antenna. The direction of a detected object from a 

radar site is determined by the position of the rotating antenna 

when the reflected portion of the radio wave is received.

Modern radar is very reliable and there are seldom outages. 

This is due to reliable maintenance and improved equipment. 

There are, however, some limitations that may affect ATC 

services and prevent a controller from issuing advisories 

concerning aircraft that are not under his or her control and 

cannot be seen on radar. 

The characteristics of radio waves are such that they normally 

travel in a continuous straight line unless they are “bent” by 

atmospheric phenomena, such as temperature inversions, 

reflected or attenuated by dense objects such as heavy clouds 

and precipitation, or screened by high terrain features. Radar 

signals degrade over distance, cannot penetrate through solid 

objects such as mountains, and the fastest radar updates every 

4.7 seconds. By contrast, the satellite signals used with 

Automatic Dependent Surveillance−Broadcast (ADS−B) do 

not degrade over distance, provide better visibility around 

mountainous terrain and allows equipped aircraft to update 

their own position once a second with better accuracy.

ATC Radar Beacon System (ATCRBS)

The ATC radar beacon system (ATCRBS) is often referred to 

as “secondary surveillance radar.” This system consists of three 

components and helps in alleviating some of the limitations 

associated with primary radar. The three components are an 

interrogator, transponder, and radarscope. The advantages of 

ATCRBS are the reinforcement of radar targets, rapid target 

identification, and a unique display of selected codes.

Growing air traffic in the National Airspace System (NAS)

will be addressed through the use of ADS-B, which not only 

If radio communication is lost, it may be a prudent decision 

to land at a non-towered airport with lower traffic volume, if 

practical. When operating at a non-towered airport, no radio 

communication is necessary. However, pilots should be extra 

vigilant when not using the radio. Other traffic may not as 
14-25

Color and Type of Signal Aircraft on the Ground Movement of Vehicles,

Equipment and Personnel Aircraft in Flight

Steady green

Flashing green

Steady red

Flashing red

Flashing white

Alternating red and green

Cleared to cross,

proceed or go

Not applicable

Stop

Clear the taxiway/runway

Return to starting point 

on airport

Exercise extreme caution!!!!

Cleared for takeoff

Cleared for taxi

Stop

Taxi clear of the runway 

in use

Return to starting point

on airport

Exercise extreme caution!!!!

Cleared to land

Return for landing (to be followed 

by steady green at the proper time)

Give way to other aircraft and

continue circling

Airport unsafe, do not land

Not applicable

Exercise extreme caution!!!!

Figure 14-42. Light gun signals.

Radar Beacon Phraseology

SQUAWK (number)

IDENT

SQUAWK (number) and IDENT

SQUAWK Standby

SQUAWK Low/Normal

SQUAWK Altitude

STOP Altitude SQUAWK

STOP SQUAWK (mode in use)

STOP SQUAWK

SQUAWK Mayday

SQUAWK VFR

Operate radar beacon transponder on designated code in MODE A/3.

Engage the “IDENT” feature (military I/P) of the transponder.

Operate transponder on specified code in MODE A/3 and engage the “IDENT” 

(military I/P) feature.

Switch transponder to standby position.

Operate transponder on low or normal sensitivity as specified. Transponder is 

operated in “NORMAL” position unless ATC specifies “LOW” (“ON” is used instead of 

“NORMAL” as a master control label on some types of transponders).

Activate MODE C with automatic altitude reporting.

Turn off altitude reporting switch and continue transmitting MODE C framing pulses. 

If your equipment does not have this capability, turn off MODE C.

Switch off specified mode. (Used for military aircraft when the controller is unaware of

military service requirements for the aircraft to continue operation on another MODE.)

Switch off transponder.

Operate transponder in the emergency position (MODE A Code 7700 for civil 

transponder, MODE 3 Code 7700 and emergency feature for military transponder).

Operate radar beacon transponder on Code 1200 in MODE A/3, or other 

appropriate VFR code.

Figure 14-43. Transponder phraseology.

provides all the same information the ATCRBS, but will do 

so more rapidly and with significantly more accuracy. By 

broadcasting aircraft position information to a ground station, 

ADS–B can also provide coverage in areas that do not have 

radar coverage. In addition, ADS–B provides trajectory 

information that includes speed and direction of motion.

Transponder

The transponder is the airborne portion of the secondary 

surveillance radar system and a system with which a pilot 

should be familiar. The ATCRBS cannot display the secondary 

information unless an aircraft is equipped with a transponder. 

A transponder is also required to operate in certain controlled 

airspace as discussed in Chapter 15, “Airspace.”

A transponder code consists of four numbers from 0 to 7 

(4,096 possible codes). There are some standard codes or ATC 

may issue a four-digit code to an aircraft. When a controller 

requests a code or function on the transponder, the word 

“squawk” may be used. Figure 14-43 lists some standard 

transponder phraseology. Additional information concerning 

transponder operation can be found in the AIM, Chapter 4.
14-26

TRACK TRACK

Traffic information would be issued to the pilot of aircraft “A”

as 12 o’clock. The actual position of the traffic as seen by 

the pilot of aircraft “A” would be 1 o’clock. Traffic information 

issued to aircraft “B” would also be given as 12 o’clock, but 

in this case, the pilot of “B” would see traffic at 10 o’clock.

Wind

A B

Figure 14-44. Traffic advisories.

Automatic Dependent Surveillance–Broadcast 

(ADS-B)

Automatic Dependent Surveillance−Broadcast (ADS−B) is a 

surveillance technology being deployed throughout the NAS 

to facilitate improvements needed to increase the capacity 

and efficiency of the NAS, while maintaining safety. ADS-B 

supports these improvements by providing a higher update rate 

and enhanced accuracy of surveillance information over the 

current radar-based surveillance system. In addition, ADS-B 

enables the expansion of air traffic control (ATC) surveillance 

services into areas where none existed previously. The ADS-B 

ground system also provides Traffic Information ServicesBroadcast (TIS-B) and Flight Information Services-Broadcast 

(FIS-B) for use on appropriately equipped aircraft, enhancing 

the user’s situational awareness (SA) and improving the 

overall safety of the NAS.

The ADS−B system is composed of aircraft avionics and a 

ground infrastructure. Onboard avionics determine the position 

of the aircraft by using the GPS and transmit its position, 

along with additional information about the aircraft, to ground 

stations for use by ATC and nearby ADS-B equipped aircraft.

In the United States, ADS−B equipped aircraft exchange 

information on one of two frequencies: 978 or 1090 MHz. 

The 1090 MHz frequency is associated with Mode A, C, and S 

transponder operations. 1090 MHz transponders with integrated 

ADS−B functionality extend the transponder message sets with 

additional ADS−B information. This additional information 

is known as an “extended squitter” message and referred to as 

1090ES. ADS−B equipment operating on 978 MHz is known 

as the Universal Access Transceiver (UAT).

Radar Traffic Advisories

Radar equipped ATC facilities provide radar assistance 

to aircraft on instrument flight plans and VFR aircraft 

provided the aircraft can communicate with the facility and 

are within radar coverage. This basic service includes safety 

alerts, traffic advisories, limited vectoring when requested, 

and sequencing at locations where this procedure has been 

established. ATC issues traffic advisories based on observed 

radar targets. The traffic is referenced by azimuth from the 

aircraft in terms of the 12-hour clock. Also, distance in 

nautical miles, direction in which the target is moving, and 

type and altitude of the aircraft, if known, are given. 

An example would be: “Traffic 10 o’clock 5 miles east 

bound, Cessna 152, 3,000 feet.” The pilot should note that 

traffic position is based on the aircraft track and that wind 

correction can affect the clock position at which a pilot locates 

traffic. This service is not intended to relieve the pilot of the 

responsibility to see and avoid other aircraft. [Figure 14-44]

In addition to basic radar service, terminal radar service 

area (TRSA) has been implemented at certain terminal 

locations. TRSAs are depicted on sectional aeronautical 

charts and listed in the Chart Supplement U.S. (formerly 

Airport/Facility Directory). The purpose of this service is to 

provide separation between all participating VFR aircraft and 

all IFR aircraft operating within the TRSA. Class C service 

provides approved separation between IFR and VFR aircraft 

and sequencing of VFR aircraft to the primary airport. Class 

B service provides approved separation of aircraft based on 

IFR, VFR, and/or weight and sequencing of VFR arrivals to 

the primary airport(s).

Wake Turbulence

All aircraft generate wake turbulence during flight. This 

disturbance is caused by a pair of counter-rotating vortices 

trailing from the wingtips. The vortices from larger aircraft 

pose problems to encountering aircraft. The wake of these 

aircraft can impose rolling moments exceeding the rollcontrol authority of the encountering aircraft. Also, the 

turbulence generated within the vortices can damage aircraft 

components and equipment if encountered at close range. For 

this reason, a pilot must envision the location of the vortex 

wake and adjust the flight path accordingly.

Vortex Generation

Lift is generated by the creation of a pressure differential over 

the wing surface. The lowest pressure occurs over the upper 

wing surface and the highest pressure under the wing. This 

pressure differential triggers the rollup of the airflow aft of 

the wing resulting in swirling air masses trailing downstream 

of the wingtips. After the rollup is completed, the wake 

consists of two counter rotating cylindrical vortices. Most of 

the energy lies within a few feet of the center of each vortex. 

[Figure 14-45]
14-27

25 

Wake begins

Rotation Touchdown

Wake ends

Figure 14-46. Vortex behavior.

Figure 14-45. Vortex generation.

Vortex Strength

Terminal Area 

Wake turbulence has historically been thought of as only 

a function of aircraft weight, but recent research considers 

additional parameters, such as speed, aspects of the wing, wake 

decay rates, and aircraft resistance to wake, just to name a few. 

The vortex characteristics of any aircraft will be changed with 

the extension of flaps or other wing configuration devices, as 

well as changing speed. However, as the basic factors are weight 

and speed, the vortex strength increases proportionately with 

an increase in aircraft operating weight or decrease in aircraft 

speed. The greatest vortex strength occurs when the generating 

aircraft is heavy, slow, and clean, since the turbulence from a 

“dirty” aircraft configuration hastens wake decay. 

En Route

En route wake turbulence events have been influenced by 

changes to the aircraft fleet mix that have more “Super” 

(A380) and “Heavy” (B-747, B-777, A340, etc.) aircraft 

operating in the NAS. There have been wake turbulence 

events in excess of 30NM and 2000 feet lower than the wake 

generating aircraft. Air density is also a factor in wake strength. 

Even though the speeds are higher in cruise at high altitude, 

the reduced air density may result in wake strength comparable 

to that in the terminal area. In addition, for a given separation 

distance, the higher speeds in cruise result in less time for the 

wake to decay before being encountered by a trailing aircraft.

Vortex Behavior

Trailing vortices have certain behavioral characteristics 

that can help a pilot visualize the wake location and take 

avoidance precautions.

Vortices are generated from the moment an aircraft leaves the 

ground (until it touches down), since trailing vortices are the 

byproduct of wing lift. [Figure 14-46] The vortex circulation 

is outward, upward, and around the wingtips when viewed 

from either ahead or behind the aircraft. Tests with large 
14-28

aircraft have shown that vortices remain spaced a bit less than 

a wingspan apart, drifting with the wind, at altitudes greater 

than a wingspan from the ground. Tests have also shown that 

the vortices sink at a rate of several hundred feet per minute, 

slowing their descent and diminishing in strength with time 

and distance behind the generating aircraft.

When the vortices of larger aircraft sink close to the ground 

(within 100 to 200 feet), they tend to move laterally over 

the ground at a speed of 2–3 knots. A crosswind decreases 

the lateral movement of the upwind vortex and increases 

the movement of the downwind vortex. A light quartering 

tailwind presents the worst case scenario as the wake 

vortices could be all present along a significant portion of 

the final approach and extended centerline and not just in the 

touchdown zone as typically expected.

Vortex Avoidance Procedures

The following procedures are in place to assist pilots in vortex 

avoidance in the given scenario. 

• Landing behind a larger aircraft on the same runway—

stay at or above the larger aircraft’s approach 

flight path and land beyond its touchdown point. 

[Figure 14-47A]

• Landing behind a larger aircraft on a parallel runway 

closer than 2,500 feet—consider the possibility of drift 

and stay at or above the larger aircraft’s final approach 

flight path and note its touchdown point. [Figure 14-47B]

• Landing behind a larger aircraft on crossing runway—

cross above the larger aircraft’s flight path. 

• Landing behind a departing aircraft on the same 

runway—land prior to the departing aircraft’s 

rotating point.

• Landing behind a larger aircraft on a crossing 

runway—note the aircraft’s rotation point and, if that 

point is past the intersection, continue and land prior 

to the intersection. If the larger aircraft rotates prior 

to the intersection, avoid flight below its flight path. 

Abandon the approach unless a landing is ensured well 

before reaching the intersection. [Figure 14-47C]

• Departing behind a large aircraft—rotate prior to the 

large aircraft’s rotation point and climb above its climb 

path until turning clear of the wake.

• For intersection takeoffs on the same runway—

be alert to adjacent larger aircraft operations, 

particularly upwind of the runway of intended use. 

If an intersection takeoff clearance is received, avoid 

headings that cross below the larger aircraft’s path.

• If departing or landing after a large aircraft executing 

a low approach, missed approach, or touch-and-go 

landing (since vortices settle and move laterally 

near the ground, the vortex hazard may exist along 

the runway and in the flight path, particularly in a 

quartering tailwind), it is prudent to wait at least 2 

minutes prior to a takeoff or landing.

• En route, it is advisable to avoid a path below and 

behind a large aircraft, and if a large aircraft is 

observed above on the same track, change the aircraft 

position laterally and preferably upwind.

Collision Avoidance

Title 14 of the CFR part 91 has established right-of-way 

rules, minimum safe altitudes, and VFR cruising altitudes 

to enhance flight safety. The pilot can contribute to collision 

avoidance by being alert and scanning for other aircraft. This 

is particularly important in the vicinity of an airport.

Effective scanning is accomplished with a series of short, 

regularly spaced eye movements that bring successive areas of 

the sky into the central visual field. Each movement should not 

exceed 10°, and each should be observed for at least 1 second 

to enable detection. Although back and forth eye movements 

seem preferred by most pilots, each pilot should develop a 

scanning pattern that is most comfortable and then adhere to 

it to assure optimum scanning. Even if entitled to the right-ofway, a pilot should yield if another aircraft seems too close.

Clearing Procedures

The following procedures and considerations are in place to 

assist pilots in collision avoidance under various situations:

• Before takeoff—prior to taxiing onto a runway or 

landing area in preparation for takeoff, pilots should 

scan the approach area for possible landing traffic, 

executing appropriate maneuvers to provide a clear 

view of the approach areas.

• Climbs and descents—during climbs and descents in 

flight conditions that permit visual detection of other 

traffic, pilots should execute gentle banks left and right 

at a frequency that permits continuous visual scanning 

of the airspace.

• Straight and level—during sustained periods of 

straight-and-level flight, a pilot should execute 

appropriate clearing procedures at periodic intervals.

• Traffic patterns—entries into traffic patterns while 

descending should be avoided.

• Traffic at VOR sites—due to converging traffic, 

sustained vigilance should be maintained in the 

vicinity of VORs and intersections.

• Training operations—vigilance should be maintained 

and clearing turns should be made prior to a practice 
14-29

Aircraft crossing over wake turbulence

Aircraft altitude is above wake

C

Touchdown point

Aircraft altitude is above wake

Less than 2500 feet

WIND

Parallel Runway Situation

B

Touchdown point of larger aircraft

WIND

A

Side view

Figure 14-47. Vortex avoidance procedures.
14-30

maneuver. During instruction, the pilot should be 

asked to verbalize the clearing procedures (call out 

“clear left, right, above, and below”).

High-wing and low-wing aircraft have their respective blind 

spots. The pilot of a high-wing aircraft should momentarily 

raise the wing in the direction of the intended turn and look 

for traffic prior to commencing the turn. The pilot of a lowwing aircraft should momentarily lower the wing and look 

for traffic prior to commencing the turn.

Pilot Deviations (PDs)

A pilot deviation (PD) is an action of a pilot that violates any 

Federal Aviation Regulation. While PDs should be avoided, 

the regulations do authorize deviations from a clearance in 

response to a traffic alert and collision avoidance system 

resolution advisory. You must notify ATC as soon as possible 

following a deviation.

Pilot deviations can occur in several different ways. 

Airborne deviations result when a pilot strays from 

an assigned heading or altitude or from an instrument 

procedure, or if the pilot penetrates controlled or restricted 

airspace without ATC clearance. 

To prevent airborne deviations, follow these steps:

• Plan each flight—you may have flown the flight many 

times before but conditions and situations can change 

rapidly, such as in the case of a pop-up temporary 

flight restriction (TFR). Take a few minutes prior to 

each flight to plan accordingly. 

• Talk and squawk—Proper communication with ATC 

has its benefits. Flight following often makes the 

controller’s job easier because they can better integrate 

VFR and IFR traffic. 

• Give yourself some room—GPS is usually more 

precise than ATC radar. Using your GPS to fly up 

to and along the line of the airspace you are trying to 

avoid could result in a pilot deviation because ATC 

radar may show you within the restricted airspace. 

Ground deviations (also called surface deviations) include 

taxiing, taking off, or landing without clearance, deviating 

from an assigned taxi route, or failing to hold short of an 

assigned clearance limit. To prevent ground deviations, stay 

alert during ground operations. Pilot deviations can and 

frequently do occur on the ground. Many strategies and tactics 

pilots use to avoid airborne deviations also work on the ground.

Pilots should also remain vigilant about vehicle/pedestrian 

deviations (V/PDs). A vehicle or pedestrian deviation 

includes pedestrians, vehicles or other objects interfering 

with aircraft operations by entering or moving on the runway 

movement area without authorization from air traffic control. 

In serious instances, any ground deviation (PD or VPD) can 

result in a runway incursion. Best practices in preventing 

ground deviations can be found in the following section 

under runway incursion avoidance. 

Runway Incursion Avoidance

A runway incursion is “any occurrence in the airport runway 

environment involving an aircraft, vehicle, person, or object 

on the ground that creates a collision hazard or results in a loss 

of required separation with an aircraft taking off, intending 

to take off, landing, or intending to land.” It is important 

to give the same attention to operating on the surface as in 

other phases of flights. Proper planning can prevent runway 

incursions and the possibility of a ground collision. A pilot 

should always be aware of the aircraft’s position on the 

surface at all times and be aware of other aircraft and vehicle 

operations on the airport. At times, towered airports can be 

busy and taxi instructions complex. In this situation, it may 

be advisable to write down taxi instructions. The following 

are some practices to help prevent a runway incursion:

• Read back all runway crossing and/or hold instructions.

• Review airport layouts as part of preflight planning, 

before descending to land and while taxiing, as 

needed.

• Know airport signage.

• Review NOTAM for information on runway/taxiway 

closures and construction areas.

• Request progressive taxi instructions from ATC when 

unsure of the taxi route.

• Check for traffic before crossing any runway hold line 

and before entering a taxiway.

• Turn on aircraft lights and the rotating beacon or strobe 

lights while taxing.

• When landing, clear the active runway as soon as 

possible, then wait for taxi instructions before further 

movement.

• Study and use proper phraseology in order to 

understand and respond to ground control instructions. 

• Write down complex taxi instructions at unfamiliar 

airports.

Approximately three runway incursions occur each day at 

towered airports within the United States. The potential 

that these numbers present for a catastrophic accident is 

unacceptable. The following are examples of pilot deviations, 

operational incidents (OI), and vehicle (driver) deviations 

that may lead to runway incursions.
14-31

Figure 14-48. Heads-up, eyes outside.

Pilot Deviations:

• Crossing a runway hold marking without clearance 

from ATC

• Taking off without clearance

• Landing without clearance 

Operational Incidents (OI):

• Clearing an aircraft onto a runway while another 

aircraft is landing on the same runway

• Issuing a takeoff clearance while the runway is 

occupied by another aircraft or vehicle 

Vehicle (Driver) Deviations:

• Crossing a runway hold marking without ATC 

clearance 

According to FAA data, approximately 65 percent of all 

runway incursions are caused by pilots. Of the pilot runway 

incursions, FAA data shows almost half of those incursions 

are caused by GA pilots.

Causal Factors of Runway Incursions

Detailed investigations of runway incursions over the past 

10 years have identified three major areas contributing to 

these events:

• Failure to comply with ATC instructions

• Lack of airport familiarity 

• Nonconformance with standard operating procedures 

Clear, concise, and effective pilot/controller communication is 

paramount to safe airport surface operations. You must fully 

understand and comply with all ATC instructions. It is mandatory 

to read back all runway “hold short” instructions verbatim.

Taxiing on an unfamiliar airport can be very challenging, 

especially during hours of darkness or low visibility. A 

request may be made for progressive taxi instructions which 

include step by step taxi routing instructions. Ensure you 

have a current airport diagram, remain “heads-up” with eyes 

outside, and devote your entire attention to surface navigation 

per ATC clearance. All checklists should be completed while 

the aircraft is stopped. There is no place for non-essential 

chatter or other activities while maintaining vigilance during 

taxi. [Figure 14-48]

Runway Confusion

Runway confusion is a subset of runway incursions and 

often results in you unintentionally taking off or landing on 

a taxiway or wrong runway. Generally, you are unaware of 

the mistake until after it has occurred. 

In August 2006, the flight crew of a commercial regional jet 

was cleared for takeoff on Runway 22 but mistakenly lined 

up and departed on Runway 26, a much shorter runway. As 

a result, the aircraft crashed off the end of the runway. 

Causal Factors of Runway Confusion

There are three major factors that increase the risk of runway 

confusion and can lead to a wrong runway departure:

• Airport complexity

• Close proximity of runway thresholds

• Joint use of a runway as a taxiway

Not only can airport complexity contribute to a runway 

incursion; it can also play a significant role in runway 

confusion. If you are operating at an unfamiliar airport and 

need assistance in executing the taxi clearance, do not hesitate 

to ask ATC for help. Always carry a current airport diagram 

and trace or highlight your taxi route to the departure runway 

prior to leaving the ramp.

If you are operating from an airport with runway thresholds 

in close proximity to one another, exercise extreme caution 

when taxiing onto the runway. Figure 14-49 shows a perfect 

example of a taxiway leading to multiple runways that may 

cause confusion. If departing on Runway 36, ensure that you 

set your aircraft heading “bug” to 360°, and align your aircraft 

to the runway heading to avoid departing from the wrong 

runway. Before adding power, make one last instrument scan 

to ensure the aircraft heading and runway heading are aligned.

Under certain circumstances, it may be necessary to 

use a runway as a taxiway. For example, during airport 

construction some taxiways may be closed requiring rerouting of traffic onto runways. In other cases, departing 

traffic may be required to back taxi on the runway in order 

to utilize the full runway length. 
14-32

36

Figure 14-49. Confusing runway/runway intersection. 

Figure 14-50. A sound practice is to write down taxi instructions 

from ATC. 

Since inattention and confusion often are factors contributing to 

runway incursion, it is important to remain extremely cautious 

and maintain situational awareness (SA). When instructed to 

use a runway as a taxiway, do not become confused and take 

off on the runway you are using as a taxiway.

ATC Instructions

Title 14 of the Code of Federal Regulations (14 CFR) part 

91, section 91.123 requires you to follow all ATC clearances 

and instructions. Request clarification if you are unsure of the 

clearance or instruction to be followed. If you are unfamiliar 

with the airport or unsure of a taxi route, ask ATC for a 

“progressive taxi.” Progressive taxi requires the controller 

to provide step-by-step taxi instructions.

The final decision to act on ATC’s instruction rests with you. 

If you cannot safely comply with any of ATC’s instructions, 

inform them immediately by using the word “UNABLE.” 

There is nothing wrong with telling a controller that you are 

unable to safely comply with the clearance. 

Another way to mitigate the risk of runway incursions is to 

write down all taxi instructions as soon as they are received 

from ATC. [Figure 14-50] It is also helpful to monitor ATC 

clearances and instructions that are issued to other aircraft. 

You should be especially vigilant if another aircraft has a 

similar sounding call sign so there is no mistake about who 

ATC is contacting or to whom they are giving instructions 

and clearances. 

Read back your complete ATC clearance with your aircraft 

call sign. This gives ATC the opportunity to clarify any 

misunderstandings and ensure that instructions were given to 

the correct aircraft. If, at any time, there is uncertainty about 

any ATC instructions or clearances, ask ATC to “say again” 

or ask for progressive taxi instructions. 

ATC Instructions—“Hold Short” 

The most important sign and marking on the airport is the 

hold sign and hold marking. These are located on a stub 

taxiway leading directly to a runway. They depict the holding 

position or the location where the aircraft is to stop so as not to 

enter the runway environment. [Figure 14-51] For example, 

Figure 14-52 shows the holding position sign and marking 

for Runway 13 and Runway 31.

When ATC issues a “hold short” clearance, you are 

expected to taxi up to, but not cross any part of the runway 

holding marking. At a towered airport, runway hold 

markings should never be crossed without explicit ATC 

instructions. Do not enter a runway at a towered airport 

unless instructions are given from ATC to cross, takeoff 

from, or “line up and wait” on that specific runway. 

ATC is required to obtain a read-back from the pilot of 

all runway “hold short” instructions. Therefore, you 

must read back the entire clearance and “hold short” 

instruction, to include runway identifier and your call sign. 
14-33

“Ground, November 1234 

ready to taxi from the GA 

ramp with Bravo.”

Pilot

“November 1234, 

Runway two seven, taxi 

via Alpha, hold short

of Runway three one.”

ATC

“November 1234, 

Runway two seven, taxi 

via Alpha, hold short

Runway three one.”

Pilot

When able, tower will 

issue crossing clearance: 

“November 1234, cross 

Runway three one.”

ATC

Figure 14-54. Communication between ATC and a pilot who is 

requesting taxi procedures. 

November 477ZA, 

Runway four, taxi via 

Echo, hold short of 

Runway two five at 

Taxiway Delta.

Controller

November 477ZA, 

Runway four via Echo, 

hold short of Runway 

two five at Delta.

Pilot

Figure 14-53. Example of taxi and “hold short” instructions from 

ATC to a pilot.

Figure 14-51. Do NOT cross a runway holding position marking 

without ATC clearance. If the tower is closed or you are operating 

from a non-towered airport, check both directions for conflicting 

traffic before crossing the hold position marking.

Figure 14-52. Runway 13-31 holding position sign and marking 

located on Taxiway Charlie.

Figure 14-53 shows an example of a controller’s taxi and “hold 

short” instructions and the reply from the pilot. 

ATC Instructions—Explicit Runway Crossing

As of June 30, 2010, ATC is required to issue explicit 

instructions to “cross” or “hold short” of each runway. 

Instructions to “cross” a runway are normally issued one at a 

time, and an aircraft must have crossed the previous runway 

before another runway crossing is issued. Exceptions may 

apply for closely spaced runways that have less than 1,000 

feet between centerlines. This applies to all runways to include 

active, inactive, or closed. Figure 14-54 shows communication 

between ATC and a pilot who is requesting a taxi clearance. 

Extra caution should be used when directed by ATC to 

taxi onto or across a runway, especially at night and during 

reduced visibility conditions. Always comply with “hold 

short” or crossing instructions when approaching an entrance 

to a runway. Scan the full length of the runway and the final 

approaches before entering or crossing any runway, even if 

ATC has issued a clearance. 

ATC Instructions—“Line Up and Wait” (LUAW)

ATC now uses the “line up and wait” (LUAW) instruction 

when a takeoff clearance cannot be issued immediately due 

to traffic or other reasons. The words “line up and wait” have 

replaced “position and hold” in directing you to taxi onto a 

runway and await takeoff clearance.

An ATC instruction to “line up and wait” is not a clearance 

for takeoff. It is only a clearance to enter the runway and 

hold in position for takeoff. Under LUAW phraseology, the 

controller states the aircraft call sign, departure runway, and 

“line up and wait.” Be aware that “traffic holding in position” 

will continue to be used to advise other aircraft that traffic 

has been authorized to line up and wait on an active runway. 

Pay close attention when instructed to “line up and wait,” 

especially at night or during periods of low visibility. Before 
14-34

entering the runway, remember to scan the full length of the 

runway and its approach end for other aircraft.

There have been collisions and incidents involving aircraft 

instructed to “line up and wait” while ATC waits for the 

necessary conditions to issue a takeoff clearance. An OI 

caused a 737 to land on a runway occupied by a twin-engine 

turboprop. The turboprop was holding in position awaiting 

takeoff clearance. Upon landing, the 737 collided with the 

twin-engine turboprop.

When ATC instructs you to “line up and wait,” they should 

advise you of any anticipated delay in receiving your takeoff 

clearance. Possible reasons for ATC takeoff clearance delays 

may include other aircraft landing and/or departing, wake 

turbulence, or traffic crossing an intersecting runway. 

• If advised of a reason for the delay, or the reason is 

clearly visible, expect an imminent takeoff clearance 

once the reason is no longer an issue.

• If a takeoff clearance is not received within 90 seconds 

after receiving the “line up and wait” instruction, 

contact ATC immediately.

• When ATC issues “line up and wait” instructions 

and takeoff clearances from taxiway intersection, the 

taxiway designator is included.

Example – “N123AG Runway One-Eight, at Charlie 

Three, line up and wait.”

Example – “N123AG Runway One-Eight, at Charlie 

Three, cleared for takeoff.”

If LUAW procedures are being used and landing traffic is a 

factor, ATC is required to:

• Inform the aircraft in the LUAW position of the closest 

aircraft that is requesting a full-stop, touch-and-go, 

stop-and-go, option, or unrestricted low approach.

Example – “N123AG, Runway One-Eight, line up 

and wait, traffic a Cessna 210 on a six-mile final.”

• In some cases, where safety logic is being used, ATC 

is permitted to issue landing clearances with traffic in 

the LUAW position. Traffic information is issued to 

the landing traffic. 

Example – “N456HK, Runway One-Eight, cleared to 

land, traffic a DeHavilland Otter holding in position.”

NOTE: ATC will/must issue a takeoff clearance to the 

traffic holding in position in sufficient time to ensure 

no conflict exists with landing aircraft. Prescribed 

runway separation must exist no later than when the 

landing aircraft crosses the threshold.

• In cases where ATC is not permitted to issue landing 

clearances with traffic in the LUAW position, traffic 

information is issued to the closest aircraft that is 

requesting a full-stop, touch-and-go, stop-and-go, 

option, or unrestricted low approach. 

Example – “N456HK, Runway One-Eight, continue, 

traffic holding in position.”

ATC Instructions—“Runway Shortened”

You should review NOTAMs in your preflight planning to 

determine any airport changes that will affect your departure 

or arrival. When the available runway length has been 

temporarily or permanently shortened due to construction, 

the ATIS includes the words “warning” and “shortened” in 

the text of the message. For the duration of the construction 

when the runway is temporarily shortened, ATC will 

include the word “shortened” in their clearance instructions. 

Furthermore, the use of the term “full length” will not be used 

by ATC during this period of the construction. 

Some examples of ATC instructions are:

• “Runway three six shortened, line up and wait.”

• “Runway three six shortened, cleared for takeoff.”

• “Runway three six shortened, cleared to land.”

When an intersection departure is requested on a temporarily 

or permanently shortened runway during the construction, 

the remaining length of runway is included in the clearance. 

For example, “Runway three six at Echo, intersection 

departure, 5,600 feet available.” If following the construction, 

the runway is permanently shortened, ATC will include 

the word “shortened” until the Chart Supplement U.S. 

(formerly Airport/Facility Directory) is updated to include 

the permanent changes to the runway length. 

Pre-Landing, Landing, and After-Landing

While en route and after receiving the destination airport 

ATIS/landing information, review the airport diagram and 

brief yourself as to your exit taxiway. Determine the following:

• Are there any runway hold markings in close proximity 

to the exit taxiway?

• Do not cross any hold markings or exit onto any 

runways without ATC clearance.

After landing, use the utmost caution where the exit taxiways 

intersect another runway, and do not exit onto another runway 

without ATC authorization. Do not accept last minute 

turnoff instructions from the control tower unless you clearly 

understand the instructions and are at a speed that ensures you 
14-35

Figure 14-55. Engineered material arresting system (EMAS) 

located at Yeager Airport, Charleston, West Virginia. 

can safely comply. Finally, after landing and upon exiting 

the runway, ensure your aircraft has completely crossed over 

the runway hold markings. Once all parts of the aircraft have 

crossed the runway holding position markings, you must hold 

unless further instructions have been issued by ATC. Do not 

initiate non-essential communications or actions until the 

aircraft has stopped and the brakes set.

Engineered Materials Arresting Systems 

(EMAS)

Aircraft can and do overrun the ends of runways and 

sometimes with devastating results. An overrun occurs 

when an aircraft passes beyond the end of a runway during 

an aborted takeoff or on landing rollout. To minimize the 

hazards of overruns, the FAA incorporated the concept of 

a runway safety area (RSA) beyond the runway end into 

airport design standards. At most commercial airports, the 

RSA is 500 feet wide and extends 1,000 feet beyond each 

end of the runway. The FAA implemented this requirement 

in the event that an aircraft overruns, undershoots, or veers 

off the side of the runway.

The most dangerous of these incidents are overruns, but 

since many airports were built before the 1,000-foot RSA 

length was adopted some 20 years ago, the area beyond the 

end of the runway is where many airports cannot achieve the 

full standard RSA. This is due to obstacles, such as bodies 

of water, highways, railroads, populated areas, or severe 

drop-off of terrain. Under these specific circumstances, the 

installation of an Engineered Materials Arresting System 

(EMAS) is an acceptable alternative to a RSA beyond the 

runway end. It provides a level of safety that is generally 

equivalent to a full RSA. [Figure 14-55]

An EMAS uses materials of closely controlled strength and 

density placed at the end of a runway to stop or greatly slow 

an aircraft that overruns the runway. The best material found 

to date is a lightweight, crushable concrete. When an aircraft 

rolls into an EMAS arrestor bed, the tires of the aircraft sink 

into the lightweight concrete and the aircraft is decelerated 

by having to roll through the material. [Figure 14-56]

Incidents

To date, there have been several incidents listed below where

the EMAS technology has worked successfully to arrest 

aircraft that overrun the runway. All cases have resulted in

minimal to do damage to the aircraft. The only known injury

was an ankle injury to a passenger during egress following

the arrestment. [Figure 14-57]

• May 1999—A Saab 340 commuter aircraft overran 

the runway at John F. Kennedy International Airport 

(JFK).

• May 2003—A Cargo McDonnell Douglas (MD)-11 

overran the runway at JFK.

• January 2005—A Boeing 747 overran the runway at 

JFK.

• July 2006—A Mystere Falcon 900 overran the 

runway at Greenville Downtown Airport (KGMU) 

in Greenville, South Carolina.

• July 2008—An Airbus A320 overran the runway at 

O’Hare International Airport (ORD).

• January 2010—A Bombardier CRJ-200 regional jet 

overran the runway at Yeager Airport (KCRW) in 

Charleston, West Virginia (WV). [Figure 14-58]

• October 2010—A G-4 Gulfstream overran the 

runway at Teterboro Airport (KTEB) in Teterboro, 

New Jersey (NJ).

• November 2011—A Cessna Citation 550 overran the 

runway at Key West International Airport (KEYW) 

in Key West, Florida.

EMAS Installations and Information

Currently, EMAS is installed at 63 runway ends at 42 airports 

in the United States with plans to install more throughout the 

next few years.

EMAS information is available in the Chart Supplement 

U.S. (formerly Airport/Facility Directory) under the specific 

airport information. Figure 14-59 shows airport information 

for Boston Logan International Airport. At the bottom of the 

page, it shows which runways are equipped with arresting 

systems and the type that they have. It is important for pilots 

to study airport information, become familiar with the details 

and limitations of the arresting system, and the runways that 

are equipped with them. [Figure 14-60]
14-36

ARRESTOR BED

Runway Set back

Runway safety area length

Side steps

Runway width

An EMASMAX bed is typically the full width of the runway and the arrestor bed is set-back from the end of the runway.

Typical Plan View

The front of an EMASMAX bed includes a lead-in ramp to transition the aircraft into the material.

• Beyond the runway width, the sides of an EMASMAX bed are stepped to provide emergency vehicle access and passenger 

 egress.

• The length of the EMAS bed is dependent upon the space available in the existing RSA and the design aircraft for the EMAS.

• As stated in FAA Advisory Circular 150/5220-22A, Engineered Materials Arresting Systems (EMAS) for Aircraft Overruns, the 

 EMAS is designed to arrest aircraft exiting the runway at speeds between 40 and 70 knots. 70 knots is the preferred EMAS 

 design runway exit speed but in limited spaces, the EMAS may have design runway exit speeds as low as 40 knots.

Typical Profile View

Typical Section View

Side steps

Stepped sides provide arff 

access and passenger egress

Arrestor bed

Arrestor bed

Debris deflector 

over concrete beam

Lead in ramp

Base surface

Base surface

Figure 14-56. Diagram of an EMASMAX system.

Pilot Considerations

Although engaging an EMAS should not be a desired 

outcome for the end of a flight, pilots need to know what 

EMAS is, how to identify it on the airfield diagram and 

on the airfield, as well as knowing what to do should they 

find themselves approaching an installation in an overrun 

situation. [Figure 14-59 and Figure 14-60] Pilots also need 

to know that an EMAS may not stop lightweight general 

aviation aircraft that are not heavy enough to sink into the 

crushable concrete. The time to discuss whether or not a 

runway has an EMAS at the end is during the pre-departure 

briefing prior to takeoff or during the approach briefing prior 

to commencing the approach. Following the guidance below 

ensures that the aircraft engages the EMAS according to the 

design entry parameters.

During the takeoff or landing phase, if a pilot determines that 

the aircraft will exit the runway end and enter the EMAS, the 

following guidance should be adhered to:

1. Continue deceleration - Regardless of aircraft speed 

upon exiting the runway, continue to follow Rejected/ 

Aborted Takeoff procedures, or if landing, Maximum 

Braking procedures outlined in the Flight Manual.
14-37

Figure 14-57. There have been several incidents where the EMAS 

has successfully arrested the aircraft. 

Figure 14-58. A Bombardier CRJ-200 regional jet overran the 

runway at Yeager Airport (KCRW) in Charleston, West Virginia. 

2. Maintain runway centerline - Not veering left or right 

of the bed and continuing straight ahead will maximize 

stopping capability of the EMAS bed. The quality of 

deceleration will be best within the confines of the bed.

3. Maintain deceleration efforts - The arrestor bed is a 

passive system, so this is the only action required by 

the pilot.

4. Once stopped, do not attempt to taxi or otherwise move 

the aircraft.

Chapter Summary

This chapter focused on airport operations both in the air and 

on the surface. For specific information about an unfamiliar 

airport, consult the Chart Supplement U.S. (formerly 

Airport/Facility Directory) and NOTAMS before flying. For 

further information regarding procedures discussed in this 

chapter, refer to 14 CFR part 91 and the AIM. By adhering 

to established procedures, both airport operations and safety 

are enhanced. 

This chapter is also designed to help you attain an 

understanding of the risks associated with surface navigation 

and is intended to provide you with basic information 

regarding the safe operation of aircraft at towered and 

nontowered airports. This chapter focuses on the following 

major areas:

• Runway incursion overview

• Taxi route planning

• Taxi procedures

• Communications

• Airport signs, markings and lighting

The chapter identifies best practices to help you avoid errors 

that may potentially lead to runway incursions. Although the 

chapter pertains mostly to surface movements for single-pilot 

operations, all of the information is relevant for flight crew 

operations as well. 

Additional information about surface operations is available 

through the following sources:

• Federal Aviation Administration (FAA) Runway 

Safety website—www.faa.gov/go/runwaysafety

• FAA National Aeronautical Navigation Services 

(AeroNav), formerly known as the National 

Aeronautical Charting Office (NACO)—www.faa.

gov/air_traffic/flight_info/aeronav

• Chart Supplement U.S. (formerly Airport/Facility 

Directory)—www.faa.gov/air_traffic/flight_info/

aeronav/digital_products/dafd/search/

• Automatic Terminal Information Service (ATIS)

• Notice to Airmen (NOTAMs)—http://www.faa.gov/

pilots/flt_plan/notams

• Advisory Circular (AC) 91-73, part 91 and part 135, 

Single-Pilot and Flight School Procedures During Taxi 

Operations

• Aeronautical Information Manual (AIM)—www.faa.

gov/air_traffic/publications/atpubs/aim/

• AC 120-74, parts 91, 121, 125, and 135, Flight Crew 

Procedures During Taxi Operations 
14-38

Not to be used for navigation

Figure 14-59. EMAS information for Boston Logan International Airport located in the Chart Supplement U.S. (formerly Airport/

Facility Directory). 
14-39

N

E-1, 28 JUL 2011 to 25 A

U

G 2011

N

E-1, 2

8

J

U

L

2

011 to

2

5

A

U

G

2

011

Not to be used for navigation

Figure 14-60. An airport diagram with EMAS information. 
14-40