Drafted — not technically validated
Record revision 2 · Runway markings and signs, the traffic pattern, the military overhead pattern and the standard radio words, with ICAO's definitions where they differ.
Definitions are quoted or closely paraphrased from the source named with each word. Meanings change between editions and theatres; the brief and the current publications take precedence.
Words of the airfield
These are the words of the airfield: the traffic pattern, the military overhead pattern and the standard radio words pilots and controllers use on the frequency. Most come from the FAA’s Pilot/Controller Glossary, which compiles the terms used in the US air traffic control system; a few, such as MARSA, apply only to military aircraft. [1]
The overhead pattern is military. Its parts, the initial, the break point, the 180 and final approach, are defined from the Navy’s air traffic controller manual, which explains that it lets fighters and some trainers enter the terminal area alongside slower aircraft flying the standard pattern. [2] Helicopter movements such as hover taxi and air taxi are defined for helicopters and VTOL aircraft of any service. [1]
Runway markings, signs and lights are defined from the FAA’s Aeronautical Information Manual, the shared US standard that military fields also use. [6] Words particular to one service are marked: the Air Force’s inside downwind, pull closed, runway supervisory unit and simulated flameout, from two of its pilot training bases; [7] [8] the Marine Corps’ expeditionary airfields; [9] and the optical landing system and arresting gear of naval air stations. [10]
Other countries. Because flying is international, the FAA glossary also prints the ICAO definition of a term wherever it differs from the FAA’s. [1] Those differences are quoted in the notes here: ceiling, flight level, ATIS, NOTAM, IFR and the traffic pattern, which ICAO calls the aerodrome traffic circuit.
72 terms
- Abeam
An aircraft is “abeam” a fix, point, or object when that fix, point, or object is approximately 90 degrees to the right or left of the aircraft track. Abeam indicates a general position rather than a precise point.
Source: [1] Pilot/Controller Glossary, letter A
- Acknowledge
Let me know that you have received and understood this message.
Source: [1] Pilot/Controller Glossary, letter A
- Advise intentions
Tell me what you plan to do.
Source: [1] Pilot/Controller Glossary, letter A
- Affirmative
Yes.
Source: [1] Pilot/Controller Glossary, letter A
- Aiming point
Two broad white stripes, one each side of the runway centerline, approximately 1,000 feet from the landing threshold.
Source: [6] Aeronautical Information Manual, ¶2-3-3.4
- Air taxi
Used to describe a helicopter/VTOL aircraft movement conducted above the surface but normally not above 100 feet AGL. The aircraft may proceed either via hover taxi or flight at speeds more than 20 knots. The pilot is solely responsible for selecting a safe airspeed/altitude for the operation being conducted.
Source: [1] Pilot/Controller Glossary, letter A
- Arresting gear
A pendant cable across a military runway that an aircraft's tailhook engages to stop it. A line of yellow retroreflective disks is painted across the runway at the cable, and yellow-circle signs mark it.
Source: [10] NAVEDTRA 14342A, p. 4-9
- ATIS
Automatic terminal information service. The continuous broadcast of recorded noncontrol information in selected terminal areas. Its purpose is to improve controller effectiveness and to relieve frequency congestion by automating the repetitive transmission of essential but routine information.
ICAO defines it more generally, as the provision of current, routine information to arriving and departing aircraft by means of continuous and repetitive broadcasts throughout the day or a specified portion of the day. [1]
Source: [1] Pilot/Controller Glossary, letter A
- Base leg
A flight path at right angles to the landing runway off its approach end. The base leg normally extends from the downwind leg to the intersection of the extended runway centerline.
Source: [1] Pilot/Controller Glossary, letter T; [2] NAVEDTRA 14342A, p. 9-11
- Break point
In the overhead approach pattern, a point, normally just above the landing threshold, where the aircraft is turned 180°, left or right depending on the direction of traffic flow, so as to be on the downwind leg.
Controllers may ask a pilot to report the break, and name the break point if it is nonstandard. [2] The brevity word BREAK is something else: an immediate maximum-performance turn. [4]
Source: [2] NAVEDTRA 14342A, p. 9-13
- Caution zone
The last 2,000 feet of an instrument runway, or half the runway length if less, where the runway edge lights are yellow instead of white.
Source: [6] Aeronautical Information Manual, ¶2-1-4.2
- Ceiling
The heights above the earth's surface of the lowest layer of clouds or obscuring phenomena that is reported as “broken,” “overcast,” or “obscuration,” and not classified as “thin” or “partial.”
ICAO's ceiling is the height above the ground or water of the base of the lowest layer of cloud below 6,000 meters (20,000 feet) covering more than half the sky. [1]
Source: [1] Pilot/Controller Glossary, letter C
- Cleared for the option
ATC authorization for an aircraft to make a touch-and-go, low approach, missed approach, stop and go, or full stop landing at the discretion of the pilot. It is normally used in training so that an instructor can evaluate a student's performance under changing situations.
Source: [1] Pilot/Controller Glossary, letter C
- Crosswind component
The wind component measured in knots at 90 degrees to the longitudinal axis of the runway.
Source: [1] Pilot/Controller Glossary, letter C
- Crosswind leg
A flight path at right angles to the landing runway off its upwind end.
Source: [1] Pilot/Controller Glossary, letter T; [2] NAVEDTRA 14342A, p. 9-11
- Datum lights
The horizontal bar of green lights either side of the optical landing system's lens box, the reference the meatball is read against.
Source: [10] NAVEDTRA 14342A, pp. 4-25, 5-52
- Displaced threshold
A threshold that is located at a point on the runway other than the designated beginning of the runway.
The pavement before a displaced threshold is available for takeoff, and for landing from the opposite direction. [6]
Source: [1] Pilot/Controller Glossary, letter D; [6] Aeronautical Information Manual, ¶2-3-3.8
- Downwind leg
A flight path parallel to the landing runway in the direction opposite to landing. The downwind leg normally extends between the crosswind leg and the base leg.
Source: [1] Pilot/Controller Glossary, letter T; [2] NAVEDTRA 14342A, p. 9-11
- Expeditionary airfield
A Marine Corps airfield built in the field. It can range from a grass landing zone for helicopters to AM-2 aluminum matting with M-31 expeditionary arresting gear, its own lighting and terminal guidance.
Source: [9] Expeditionary Airfields
- FCLP
Field carrier landing practice. Carrier-style approaches flown to a runway equipped with an optical landing system, worked by a landing signal officer.
Source: [10] NAVEDTRA 14342A, p. 4-25
- Final approach
A flight path in the direction of landing along the extended runway centerline. The final approach normally extends from the base leg to the runway. An aircraft making a straight-in approach VFR is also considered to be on final approach.
The Navy's controller manual adds that every arriving aircraft, whatever its type or approach, flies at least this one common component of the standard traffic pattern. [2]
Source: [1] Pilot/Controller Glossary, letter T; [2] NAVEDTRA 14342A, p. 9-14
- Flight level
A level of constant atmospheric pressure related to a reference datum of 29.92 inches of mercury. Each is stated in three digits that represent hundreds of feet; flight level (FL) 250 represents a barometric altimeter indication of 25,000 feet.
ICAO states the same standard datum in hectopascals: 1013.2 hPa. [1]
Source: [1] Pilot/Controller Glossary, letter F
- Go around
Instructions for a pilot to abandon his/her approach to landing. Unless otherwise advised by ATC, a VFR aircraft or an aircraft conducting visual approach should overfly the runway while climbing to traffic pattern altitude and enter the traffic pattern via the crosswind leg. A pilot on an IFR flight plan making an instrument approach should execute the published missed approach procedure or proceed as instructed by ATC.
Source: [1] Pilot/Controller Glossary, letter G
- Holding position marking
Four yellow lines across a taxiway, two solid and two dashed. The solid lines are always on the side where the aircraft must hold.
Source: [6] Aeronautical Information Manual, ¶2-3-5.1
- Hover taxi
Used to describe a helicopter/VTOL aircraft movement conducted above the surface and in ground effect at airspeeds less than approximately 20 knots. The actual height may vary, and some helicopters may require hover taxi above 25 feet AGL to reduce ground effect turbulence or provide clearance for cargo slingloads.
Source: [1] Pilot/Controller Glossary, letter H
- I say again
The message will be repeated.
Source: [1] Pilot/Controller Glossary, letter I
- IFR
Instrument flight rules. Rules governing the procedures for conducting instrument flight. Also a term used by pilots and controllers to indicate type of flight plan.
ICAO's definition is a set of rules governing the conduct of flight under instrument meteorological conditions. [1]
Source: [1] Pilot/Controller Glossary, letter I
- Immediately
Used by ATC or pilots when such action compliance is required to avoid an imminent situation.
Source: [1] Pilot/Controller Glossary, letter I
- Initial
The initial approach of the overhead pattern: a line of flight along the extended centerline of the landing runway, 3 to 5 miles long, normally flown 500 feet above the standard traffic pattern altitude.
Controllers may ask the pilot to report the initial. [2] The FAA glossary's overhead maneuver gives the same 3 to 5 miles and at least 500 feet above the conventional pattern. [1]
Source: [2] NAVEDTRA 14342A, p. 9-13
- Inside downwind
The downwind leg reached by the break or by pulling closed, within about 1.5 nautical miles of the runway.
Source: [7] Columbus Collision Avoidance: A guide to Columbus Air Force Base and the surrounding area, Military traffic pattern
- Location sign
A sign with a black background, yellow inscription and yellow border. A taxiway location sign tells the pilot which taxiway the aircraft is on.
Source: [6] Aeronautical Information Manual, ¶2-3-9
- Low approach
An approach over an airport or runway following an instrument approach or a VFR approach including the go-around maneuver where the pilot intentionally does not make contact with the runway.
Source: [1] Pilot/Controller Glossary, letter L
- Mandatory instruction sign
A sign with a red background and white inscription. It marks the entrance to a runway or critical area, or an area aircraft may not enter.
Source: [6] Aeronautical Information Manual, ¶2-3-8
- MARSA
Military authority assumes responsibility for separation of aircraft. A condition whereby the military services involved assume responsibility for separation between participating military aircraft in the ATC system. It is used only for required IFR operations which are specified in letters of agreement or other appropriate FAA or military documents.
Source: [1] Pilot/Controller Glossary, letter M
- Mayday
The international radiotelephony distress signal. When repeated three times, it indicates imminent and grave danger and that immediate assistance is requested.
Source: [1] Pilot/Controller Glossary, letter M
- Meatball
The yellow light of the optical landing system, read against the datum lights to see where the aircraft is on the glide slope. It rises above the datum lights as the pilot rises above the glide slope.
The pilot's report that it is in sight is the ball call; see Ball in the carrier terms.
Source: [10] NAVEDTRA 14342A, pp. 4-25, 5-52
- Military training routes
Airspace of defined vertical and lateral dimensions established for the conduct of military flight training at airspeeds in excess of 250 knots IAS.
IFR routes (IR) and VFR routes (VR) are flown below 10,000 feet MSL. [1]
Source: [1] Pilot/Controller Glossary, letter M
- Minimum fuel
Indicates that an aircraft's fuel supply has reached a state where, upon reaching the destination, it can accept little or no delay. This is not an emergency situation but merely indicates an emergency situation is possible should any undue delay occur.
Not the same as the brevity words JOKER and BINGO, which are pre-briefed fuel states for a mission. [4]
Source: [1] Pilot/Controller Glossary, letter M
- Negative
“No,” or “permission not granted,” or “that is not correct.”
Source: [1] Pilot/Controller Glossary, letter N
- Negative contact
Used by pilots to inform ATC that previously issued traffic is not in sight, which may be followed by a request for help avoiding it; or that they were unable to contact ATC on a particular frequency.
Source: [1] Pilot/Controller Glossary, letter N
- NOTAM
Notice to airmen. A notice containing information (not known sufficiently in advance to publicize by other means) concerning the establishment, condition, or change in any component (facility, service, or procedure of, or hazard in the National Airspace System) the timely knowledge of which is essential to personnel concerned with flight operations.
ICAO's definition is not limited to one country's airspace: a change in any aeronautical facility, service, procedure or hazard. [1]
Source: [1] Pilot/Controller Glossary, letter N
- Out
The conversation is ended and no response is expected.
Source: [1] Pilot/Controller Glossary, letter O
- Over
My transmission is ended; I expect a response.
Source: [1] Pilot/Controller Glossary, letter O
- Overhead maneuver
A series of predetermined maneuvers prescribed for aircraft (often in formation) for entry into the visual flight rules (VFR) traffic pattern and to proceed to a landing. It usually specifies an initial approach 3 to 5 miles long, an elliptical pattern of two 180-degree turns starting at a break point, an altitude at least 500 feet above the conventional pattern, and a roll-out on final not less than 1/4 mile from the threshold and not less than 300 feet above the ground.
The Navy calls it the overhead approach pattern, made of the initial approach, break point, “the 180” and final approach, and uses it so that fighters and some trainers can join the terminal area alongside slower aircraft flying the standard pattern. [2] An aircraft flying it is VFR; an IFR flight plan is canceled at the initial point. [1]
Source: [1] Pilot/Controller Glossary, letter O; [2] NAVEDTRA 14342A, p. 9-13
- Pan-pan
The international radio-telephony urgency signal. When repeated three times, indicates uncertainty or alert followed by the nature of the urgency.
Source: [1] Pilot/Controller Glossary, letter P
- PAPI
Precision approach path indicator. A visual glide slope indicator of two or four light units in a single row, normally on the left side of the runway. Each unit shows red or white depending on whether the aircraft is below or above its angle.
Source: [6] Aeronautical Information Manual, ¶2-1-2.2
- PAR
Precision approach radar. Radar equipment in some ATC facilities operated by the FAA and/or the military services at joint-use civil/military locations and separate military installations to detect and display azimuth, elevation, and range of aircraft on the final approach course to a runway. It is primarily used to conduct a precision instrument approach wherein the controller issues guidance instructions to the pilot.
Source: [1] Pilot/Controller Glossary, letter P
- Pull closed
Climb and turn straight back onto the inside downwind after a touch-and-go or low approach, instead of flying the whole pattern again.
Source: [7] Columbus Collision Avoidance: A guide to Columbus Air Force Base and the surrounding area, Military traffic pattern
- Read back
Repeat my message back to me.
Source: [1] Pilot/Controller Glossary, letter R
- Roger
I have received all of your last transmission. It should not be used to answer a question requiring a yes or a no answer.
The multi-service brevity word ROGER adds that it does not indicate compliance or reaction. [4]
Source: [1] Pilot/Controller Glossary, letter R
- RSU
Runway supervisory unit. A unit by the runway that runs an Air Force training base's trainer pattern on its own frequency, alongside the tower.
Source: [7] Columbus Collision Avoidance: A guide to Columbus Air Force Base and the surrounding area, Military traffic pattern; T-6
- Runway designator
The number at each end of a runway, the whole number nearest one-tenth of its magnetic direction, with L, C or R added for parallel runways.
Source: [6] Aeronautical Information Manual, ¶2-3-3.2
- Say again
Used to request a repeat of the last transmission. Usually specifies transmission or portion thereof not understood or received.
Source: [1] Pilot/Controller Glossary, letter S
- SFO
Simulated flameout. A practice engine-out pattern flown by single-engine jets and trainers, a glide from high altitude to the runway with a very high rate of descent. Also called an emergency landing pattern (ELP).
Source: [8] Midair Collision Avoidance (MACA) Handbook, Kelly Field; ELP
- Speak slower
Used in verbal communications as a request to reduce speech rate.
Source: [1] Pilot/Controller Glossary, letter S
- Squawk (mode, code, function)
Used by ATC to instruct a pilot to activate the aircraft transponder and ADS-B Out with altitude reporting enabled, or (military) to activate only specific modes, codes, or functions.
Source: [1] Pilot/Controller Glossary, letter S
- Stand by
The controller or pilot must pause for a few seconds, usually to attend to other duties of a higher priority. Also means to wait, as in “stand by for clearance.” The caller should reestablish contact if a delay is lengthy. “Stand by” is not an approval or denial.
Source: [1] Pilot/Controller Glossary, letter S
- Stop and go
A procedure wherein an aircraft will land, make a complete stop on the runway, and then commence a takeoff from that point.
Source: [1] Pilot/Controller Glossary, letter S
- TACAN
Tactical air navigation. An ultra-high frequency electronic rho-theta air navigation aid which provides suitably equipped aircraft a continuous indication of bearing and distance to the TACAN station.
The Navy's controller manual adds that TACAN has 126 two-way channels, that its distance element is DME, and that its compact ground equipment can be transported and set up more easily than a VOR. [3]
Source: [1] Pilot/Controller Glossary, letter T; [3] NAVEDTRA 14342A, p. 2-28
- Tetrahedron
A device normally located on uncontrolled airports and used as a landing direction indicator. The small end of a tetrahedron points in the direction of landing. At controlled airports, the tetrahedron, if installed, should be disregarded because tower instructions supersede the indicator.
Source: [1] Pilot/Controller Glossary, letter T
- The 180
In the overhead approach pattern, the second 180° turn, made after the downwind leg to establish the aircraft on final approach. The aircraft stays at traffic pattern altitude until the turn is started.
Navy carrier training uses the same name for the point from which the LSO controls the aircraft to touchdown; see the carrier terms. [5]
Source: [2] NAVEDTRA 14342A, p. 9-14
- Threshold
The beginning of that portion of the runway usable for landing.
Source: [1] Pilot/Controller Glossary, letter T
- Touch-and-go
An operation by an aircraft that lands and departs on a runway without stopping or exiting the runway.
Source: [1] Pilot/Controller Glossary, letter T
- Touchdown zone markings
Groups of one, two and three bars in pairs either side of the runway centerline, coded to give distance from the threshold in 500-foot increments.
Source: [6] Aeronautical Information Manual, ¶2-3-3.5
- Traffic pattern
The traffic flow that is prescribed for aircraft landing at, taxiing on, or taking off from an airport. The components of a typical traffic pattern are departure, upwind leg, crosswind leg, downwind leg, base leg, and final approach.
ICAO calls it the aerodrome traffic circuit: the specified path to be flown by aircraft operating in the vicinity of an aerodrome. [1] Navy airfields normally fly left-hand traffic, with right-hand traffic when required. [2]
Source: [1] Pilot/Controller Glossary, letters T, A; [2] NAVEDTRA 14342A, p. 9-11
- Unable
Indicates inability to comply with a specific instruction, request, or clearance.
Source: [1] Pilot/Controller Glossary, letter U
- Upwind leg
A flight path that begins after departure and continues straight ahead along the extended runway centerline. Upwind leg is an extension of departure and is used when issuing control instructions for separation, spacing or sequencing.
Source: [1] Pilot/Controller Glossary, letter T; [2] NAVEDTRA 14342A, p. 9-11
- Verify
Request confirmation of information; e.g., “verify assigned altitude.”
Source: [1] Pilot/Controller Glossary, letter V
- VFR
Visual flight rules. Rules that govern the procedures for conducting flight under visual conditions. The term “VFR” is also used in the United States to indicate weather conditions that are equal to or greater than minimum VFR requirements. In addition, it is used by pilots and controllers to indicate type of flight plan.
Source: [1] Pilot/Controller Glossary, letter V
- Wave-off lights
Flashing red lights on the optical landing system, worked by the landing signal officer, that tell the pilot to go around.
Source: [10] NAVEDTRA 14342A, p. 4-25
- Wilco
I have received your message, understand it, and will comply with it.
Source: [1] Pilot/Controller Glossary, letter W
- Words twice
As a request: “Communication is difficult. Please say every phrase twice.” As information: “Since communications are difficult, every phrase in this message will be spoken twice.”
Source: [1] Pilot/Controller Glossary, letter W
Sources
- Pilot/Controller Glossary. Federal Aviation Administration. https://www.faa.gov/air_traffic/publications/atpubs/pcg_html/index.html (accessed 2026-10-26). Each word is cited by the letter section it appears under. The glossary includes ICAO definitions, marked [ICAO], where they differ from the FAA's; the notes on this page quote them.
- NAVEDTRA 14342A, Air Traffic Controller, chapter 9: Traffic patterns. US Navy, Naval Education and Training Professional Development and Technology Center (copy hosted by Integrated Publishing). https://navyaviation.tpub.com/14342A/Overhead-Approach-Pattern-Components-327.html (accessed 2026-10-26). Printed pages 9-11 (standard traffic pattern), 9-13 (overhead approach pattern components) and 9-14 (the 180, final approach and overhead landing information); the neighbouring pages of the copy hold 9-11 and 9-14.
- NAVEDTRA 14342A, Air Traffic Controller, chapter 2: Tactical Air Navigation (TACAN) system. US Navy, Naval Education and Training Professional Development and Technology Center (copy hosted by Integrated Publishing). https://navyaviation.tpub.com/14342A/Tactical-Air-Navigation-Tacan-System-105.html (accessed 2026-10-26). Printed page 2-28.
- ATP 1-02.1 / MCRP 3-30B.1 / NTTP 6-02.1 / AFTTP 3-2.5, Brevity: Multi-Service Tactics, Techniques, and Procedures for Multi-Service Brevity Codes. Air Land Sea Application Center for the US Army, Marine Corps, Navy and Air Force, 28 May 2020, Change 1 of 2 April 2021. https://irp.fas.org/doddir/army/atp1-02-1.pdf (accessed 2026-10-26). Table 2: BINGO p. 5, BREAK p. 7, JOKER p. 28, ROGER p. 41.
- CNATRA P-816, CV Procedures (UMFO), T-45C. Naval Air Training Command (third-party copy), Revision 28 January 2014, Change 1 of 9 February 2018. https://murphysys.com/dcs/P-816.pdf (accessed 2026-10-26). Appendix A glossary, Landing Signals Officer, p. A-4.
- Aeronautical Information Manual, chapter 2: Aeronautical Lighting and Other Airport Visual Aids. Federal Aviation Administration. https://www.faa.gov/air_traffic/publications/atpubs/aim_html/chap2_section_3.html (accessed 2026-10-25). Section 1, Airport Lighting Aids (¶2-1-2, 2-1-4) and section 3, Airport Marking Aids and Signs (¶2-3-3 to 2-3-9), current online edition. Cited by paragraph.
- Columbus Collision Avoidance: A guide to Columbus Air Force Base and the surrounding area. 14th Flying Training Wing Safety Office, Columbus Air Force Base (PDF hosted by Tupelo Regional Airport), October 2013. https://flytupelo.com/wp-content/uploads/2020/12/MACA-Booklet.pdf (accessed 2026-10-25). The "Military Traffic Pattern" and T-6 sections. An Air Force wing's guide for civil pilots; dated, so its numbers are an example.
- Midair Collision Avoidance (MACA) Handbook. Joint Base San Antonio. https://www.jbsa.mil/Portals/102/Documents/Safety/JBSA-MACA_Pamphlet_2024.pdf (accessed 2026-10-25). The JBSA-Kelly Field and emergency landing pattern (ELP) sections.
- Expeditionary Airfields. Naval Air Systems Command. https://www.navair.navy.mil/product/expeditionary-airfields-0 (accessed 2026-10-25).
- NAVEDTRA 14342A, Air Traffic Controller, chapters 4 and 5: Airfield equipment and optical landing systems. US Navy, Naval Education and Training Professional Development and Technology Center (copy hosted by Integrated Publishing). https://navyaviation.tpub.com/14342A/ (accessed 2026-10-25). Printed pages 4-9 (arresting gear), 4-25 (optical landing system at naval air stations) and 5-52 (IFLOLS).