Commercial Pilot — Airplane

SeeVISUAL METEOROLOGICAL CONDITIONS

SeeAERONAUTICAL INFORMATION MANUAL

SeeVISUAL FLIGHT RULES

1. When used concerning the traffic pattern, the word means “crosswind leg.”

SeeTRAFFIC PATTERN

1. When used concerning wind conditions, the word means a wind not parallel to the runway or the path of an aircraft.

SeeCROSSWIND COMPONENT

An atmospheric phenomenon that causes changes in aircraft altitude, attitude, and or airspeed with aircraft reaction depending on intensity. Pilots report turbulence intensity according to aircraft's reaction as follows:

1. Light - Causes slight, erratic changes in altitude and or attitude (pitch, roll, or yaw).
2. Moderate- Similar to Light but of greater intensity. Changes in altitude and or attitude occur but the aircraft remains in positive control at all times. It usually causes variations in indicated airspeed.
3. Severe- Causes large, abrupt changes in altitude and or attitude. It usually causes large variations in indicated airspeed. Aircraft may be momentarily out of control.
4. Extreme- The aircraft is violently tossed about and is practically impossible to control. It may cause structural damage.

SeeCHOP

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SeeAIR TRAFFIC CONTROL

A phenomenon that occurs when an aircraft develops lift and forms a pair of counter‐rotating vortices.

SeeAIRCRAFT CLASSES

SeeAIRCRAFT WAKE CATEGORIES

SeeVORTICES

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SeeALONG-TRACK DISTANCE

Any wind more than 90 degrees to the longitudinal axis of the runway. The magnetic direction of the runway must be used as the basis for determining the longitudinal axis.

Any locality either on land, water, or structures, including airports/heliports and intermediate landing fields, which is used, or intended to be used, for the landing and takeoff of aircraft whether or not facilities are provided for the shelter, servicing, or for receiving or discharging passengers or cargo.

SeeICAO term LANDING AREA

An existing object, object of natural growth, or terrain at a fixed geographical location or which may be expected at a fixed location within a prescribed area with reference to which vertical clearance is or must be provided during flight operation.

Aircraft operating in the air or on an airport surface, exclusive of loading ramps and parking areas.

SeeICAO term AIR TRAFFIC

A service operated by appropriate authority to promote the safe, orderly and expeditious flow of air traffic.

SeeICAO term AIR TRAFFIC CONTROL SERVICE

When used as a control instruction should be followed by another word or words clarifying what is expected of the pilot. Example: “continue taxi,” “continue descent,” “continue inbound,” etc.

A heavier‐than‐air aircraft that depends principally for its support in flight on the lift generated by one or more rotors.

SeeINSTRUMENT APPROACH PROCEDURE

A device that provides information on range, azimuth, and/or elevation of objects by measuring the time interval between transmission and reception of directional radio pulses and correlating the angular orientation of the radiated antenna beam or beams in azimuth and/or elevation.

1. Primary Radar- A radar system in which a minute portion of a radio pulse transmitted from a site is reflected by an object and then received back at that site for processing and display at an air traffic control facility.
2. Secondary Radar/Radar Beacon (ATCRBS)- A radar system in which the object to be detected is fitted with cooperative equipment in the form of a radio receiver/transmitter (transponder). Radar pulses transmitted from the searching transmitter/receiver (interrogator) site are received in the cooperative equipment and used to trigger a distinctive transmission from the transponder. This reply transmission, rather than a reflected signal, is then received back at the transmitter/receiver site for processing and display at an air traffic control facility.

SeeCOOPERATIVE SURVEILLANCE

SeeINTERROGATOR

SeeNON-COOPERATIVE SURVEILLANCE

SeeTRANSPONDER

SeeICAO term RADAR

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Flights that are required to land at other than their original destination for reasons beyond the control of the pilot/company, e.g. periods of significant weather.

Specified information relating to the intended flight of an aircraft that is filed electronically, orally, or in writing with an FSS, third-party vendor, or an ATC facility.

SeeFAST FILE

SeeFILED

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SeeAPRON

The actual flight path of an aircraft over the surface of the earth.

SeeCOURSE

SeeFLIGHT PATH

SeeROUTE

SeeICAO term TRACK

(See LAND AND HOLD SHORT OPERATIONS.)

(When used with communication transfer) listen on a specific frequency and stand by for instructions. Under normal circumstances do not establish communications.

The conversation is ended and no response is expected.

The general term that describes the change from one phase of flight or flight condition to another; e.g., transition from en route flight to the approach or transition from instrument flight to visual flight.

SeeVFR AIRCRAFT

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.

SeeINSTRUMENT FLIGHT RULES

SeeINSTRUMENT METEOROLOGICAL CONDITIONS

SeeVISUAL METEOROLOGICAL CONDITIONS

Refer to14 CFR part 91

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Let me know that you have received and understood this message.

Dead reckoning, as applied to flying, is the navigation of an airplane solely by means of computations based on airspeed, course, heading, wind direction, and speed, groundspeed, and elapsed time.

A rotorcraft that, for its horizontal motion, depends principally on its engine‐driven rotors.

SeeROTORCRAFT

Used by ATC or pilots when such action compliance is required to avoid an imminent situation.

Operations that include simultaneous takeoffs and landings and/or simultaneous landings when a landing aircraft is able and is instructed by the controller to hold short of an intersecting runway or taxiway, a predetermined point, or an approach/departure flightpath. Pilots are expected to promptly inform the controller if the hold short clearance cannot be accepted.

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The common network of U.S. airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and services; rules, regulations and procedures, technical information, and manpower and material. Included are system components shared jointly with the military.

LIFT- A heavier‐than‐air aircraft capable of vertical takeoff, vertical landing, and low‐speed flight that depends principally on engine‐driven lift devices during these flight regimes and on nonrotating airfoil(s) for lift during horizontal flight. Powered‐lift aircraft can operate on routes or altitudes specifically prescribed for powered‐lift by the FAA.

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.

1. 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.
2. Crosswind Leg- A flight path at right angles to the landing runway off its upwind end.
3. 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.
4. 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.

NOTE-
ATC may instruct a pilot to report a “2‐mile left base” to Runway 22. This instruction means that the pilot is expected to maneuver their aircraft into a left base leg that will intercept a straight‐in final 2 miles from the approach end of Runway 22 and advise ATC.

REFERENCE-
Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25, Chapter 14, Airport Operations, Traffic Patterns.

1. 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.

NOTE-
ATC may instruct a pilot to report “5‐mile final” to Runway 22. This instruction means that the pilot should maneuver their aircraft onto a straight‐in final and advise ATC when they are five miles from the approach end of Runway 22.

1. Departure- The flight path that begins after takeoff and continues straight ahead along the extended runway centerline. The departure climb continues until reaching a point at least 1/2 mile beyond the departure end of the runway and within 300 feet of the traffic pattern altitude.

REFERENCE-
Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25, Chapter 14, Airport Operations, Traffic Patterns.

SeeSTRAIGHT‐IN APPROACH VFR

SeeTAXI PATTERNS

SeeICAO term AERODROME TRAFFIC CIRCUIT

Refer to14 CFR part 91

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The ability, as determined by atmospheric conditions and expressed in units of distance, to see and identify prominent unlighted objects by day and prominent lighted objects by night. Visibility is reported as statute miles, hundreds of feet or meters.

Refer to14 CFR part 91

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1. Flight Visibility- The average forward horizontal distance, from the cockpit of an aircraft in flight, at which prominent unlighted objects may be seen and identified by day and prominent lighted objects may be seen and identified by night.
2. Ground Visibility- Prevailing horizontal visibility near the earth's surface as reported by the United States National Weather Service or an accredited observer.
3. Prevailing Visibility- The greatest horizontal visibility equaled or exceeded throughout at least half the horizon circle which need not necessarily be continuous.
4. Runway Visual Range (RVR)- An instrumentally derived value, based on standard calibrations, that represents the horizontal distance a pilot will see down the runway from the approach end. It is based on the sighting of either high intensity runway lights or on the visual contrast of other targets whichever yields the greater visual range. RVR, in contrast to prevailing or runway visibility, is based on what a pilot in a moving aircraft should see looking down the runway. RVR is horizontal visual range, not slant visual range. It is based on the measurement of a transmissometer made near the touchdown point of the instrument runway and is reported in hundreds of feet. RVR, where available, is used in lieu of prevailing visibility in determining minimums for a particular runway.
5. Touchdown RVR- The RVR visibility readout values obtained from RVR equipment serving the runway touchdown zone.
6. Mid‐RVR- The RVR readout values obtained from RVR equipment located midfield of the runway.
7. Rollout RVR- The RVR readout values obtained from RVR equipment located nearest the rollout end of the runway.

SeeICAO term FLIGHT VISIBILITY

SeeICAO term GROUND VISIBILITY

SeeICAO term RUNWAY VISUAL RANGE

SeeICAO term VISIBILITY

An aircraft is considered airborne when all parts of the aircraft are off the ground.

The number assigned to a particular multiple pulse reply signal transmitted by a transponder.

SeeDISCRETE CODE

The engine which, upon failure, would most adversely affect the performance or handling qualities of an aircraft.

Designates which sector is eligible to exchange CPDLC messages with a specific aircraft.

To be stable or fixed at an altitude or on a course, route, route segment, heading, instrument approach or departure procedure, etc.

The accumulation of airframe ice.

Types of icing are:

1. Rime Ice- Rough, milky, opaque ice formed by the instantaneous freezing of small supercooled water droplets.
2. Clear Ice- A glossy, clear, or translucent ice formed by the relatively slow freezing of large supercooled water droplets.
3. Mixed- A mixture of clear ice and rime ice.

Intensity of icing:

1. Trace- Ice becomes noticeable. The rate of accumulation is slightly greater than the rate of sublimation. A representative accretion rate for reference purposes is less than ¼ inch (6 mm) per hour on the outer wing. The pilot should consider exiting the icing conditions before they become worse.
2. Light- The rate of ice accumulation requires occasional cycling of manual deicing systems to minimize ice accretions on the airframe. A representative accretion rate for reference purposes is ¼ inch to 1 inch (0.6 to 2.5 cm) per hour on the unprotected part of the outer wing. The pilot should consider exiting the icing condition.
3. Moderate- The rate of ice accumulation requires frequent cycling of manual deicing systems to minimize ice accretions on the airframe. A representative accretion rate for reference purposes is 1 to 3 inches (2.5 to 7.5 cm) per hour on the unprotected part of the outer wing. The pilot should consider exiting the icing condition as soon as possible.
4. Severe- The rate of ice accumulation is such that ice protection systems fail to remove the accumulation of ice and ice accumulates in locations not normally prone to icing, such as areas aft of protected surfaces and any other areas identified by the manufacturer. A representative accretion rate for reference purposes is more than 3 inches (7.5 cm) per hour on the unprotected part of the outer wing. By regulation, immediate exit is required.

The situation which exists when the position indication of a particular aircraft is seen on a situation display and positively identified.

Weather condition requirements established for a particular operation or type of operation; e.g., IFR takeoff or landing, alternate airport for IFR flight plans, VFR flight, etc.

SeeIFR CONDITIONS

SeeIFR TAKEOFF MINIMUMS AND DEPARTURE PROCEDURES

SeeLANDING MINIMUMS

SeeVFR CONDITIONS

Refer to14 CFR part 91

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The portion of a runway available for landing and roll‐out for aircraft cleared for LAHSO. This distance is measured from the landing threshold to the hold‐short point.

Used in an ATC clearance to authorize a pilot to conduct flight at any altitude from the minimum IFR altitude up to and including the altitude specified in the clearance. The pilot may level off at any intermediate altitude within this block of airspace. Climb/descent within the block is to be made at the discretion of the pilot. However, once the pilot starts descent and verbally reports leaving an altitude in the block, he/she may not return to that altitude without additional ATC clearance. Further, it is approval for the pilot to proceed to and make an approach at destination airport and can be used in conjunction with:

1. An airport clearance limit at locations with a standard/special instrument approach procedure. The CFRs require that if an instrument letdown to an airport is necessary, the pilot must make the letdown in accordance with a standard/special instrument approach procedure for that airport, or
2. An airport clearance limit at locations that are within/below/outside controlled airspace and without a standard/special instrument approach procedure. Such a clearance is NOT AUTHORIZATION for the pilot to descend under IFR conditions below the applicable minimum IFR altitude nor does it imply that ATC is exercising control over aircraft in Class G airspace; however, it provides a means for the aircraft to proceed to destination airport, descend, and land in accordance with applicable CFRs governing VFR flight operations. Also, this provides search and rescue protection until such time as the IFR flight plan is closed.

SeeINSTRUMENT APPROACH PROCEDURE

When used in NOTAMs “EST” is a contraction that is used by the issuing authority only when the condition is expected to return to service prior to the expiration time. Using “EST” lets the user know that this NOTAM has the possibility of returning to service earlier than the expiration time. Any NOTAM which includes an “EST” will be auto-expired at the designated expiration time.

The time the flight is estimated to arrive at the gate (scheduled operators) or the actual runway on times for nonscheduled operators.

Commonly used to mean that an aircraft is on the final approach course or is aligned with a landing area.

SeeFINAL APPROACH COURSE

SeeFINAL APPROACH‐IFR

SeeSEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE

That part of an instrument approach procedure which commences at the specified final approach fix or point, or where such a fix or point is not specified.

1. At the end of the last procedure turn, base turn or inbound turn of a racetrack procedure, if specified; or
2. At the point of interception of the last track specified in the approach procedure; and ends at a point in the vicinity of an aerodrome from which:
3. A landing can be made; or
4. A missed approach procedure is initiated.

The ability of a system to provide timely warnings to users when the system should not be used for navigation.

An LM/MF NDB used as an aid to final approach.

SeeNATIONAL AIRSPACE SYSTEM

Repeat my message back to me.

A weather advisory issued concerning weather significant to the safety of all aircraft. SIGMET advisories cover severe and extreme turbulence, severe icing, and widespread dust or sandstorms that reduce visibility to less than 3 miles.

SeeAIRMET

SeeCONVECTIVE SIGMET

SeeCWA

SeeGRAPHICAL AIRMEN'S METEOROLOGICAL INFORMATION

SeeICAO term SIGMET INFORMATION

SeeSAW

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Airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature and/or wherein limitations may be imposed upon aircraft operations that are not a part of those activities. Types of special use airspace are:

1. Alert Area- Airspace which may contain a high volume of pilot training activities or an unusual type of aerial activity, neither of which is hazardous to aircraft. Alert Areas are depicted on aeronautical charts for the information of nonparticipating pilots. All activities within an Alert Area are conducted in accordance with Federal Aviation Regulations, and pilots of participating aircraft as well as pilots transiting the area are equally responsible for collision avoidance.
2. Controlled Firing Area- Airspace wherein activities are conducted under conditions so controlled as to eliminate hazards to nonparticipating aircraft and to ensure the safety of persons and property on the ground.
3. Military Operations Area (MOA)- Permanent and temporary MOAs are airspace established outside of Class A airspace area to separate or segregate certain nonhazardous military activities from IFR traffic and to identify for VFR traffic where these activities are conducted. Permanent MOAs are depicted on Sectional Aeronautical, VFR Terminal Area, and applicable En Route Low Altitude Charts.

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1. National Security Area (NSA)– Airspace of defined vertical and lateral dimensions established at locations where there is a requirement for increased security of ground facilities. Pilots are requested to voluntarily avoid flying through the depicted NSA. When a greater level of security is required, flight through an NSA may be temporarily prohibited by establishing a TFR under the provisions of 14 CFR section 99.7. Such prohibitions will be issued by FAA Headquarters and disseminated via the U.S. NOTAM System.

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1. Prohibited Area- Airspace designated under 14 CFR part 73 within which no person may operate an aircraft without the permission of the using agency.

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Refer toEn Route Charts

1. Restricted Area- Permanent and temporary restricted areas are airspace designated under 14 CFR part 73, within which the flight of aircraft, while not wholly prohibited, is subject to restriction. Most restricted areas are designated joint use and IFR/VFR operations in the area may be authorized by the controlling ATC facility when it is not being utilized by the using agency. Permanent restricted areas are depicted on Sectional Aeronautical, VFR Terminal Area, and applicable En Route charts. Where joint use is authorized, the name of the ATC controlling facility is also shown.

Refer to14 CFR part 73

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1. Warning Area- A warning area is airspace of defined dimensions extending from 3 nautical miles outward from the coast of the United States, that contains activity that may be hazardous to nonparticipating aircraft. The purpose of such warning area is to warn nonparticipating pilots of the potential danger. A warning area may be located over domestic or international waters or both.

To taxi a float plane at full power or high RPM.

SeeLANDING AREA

The airborne radar beacon receiver/transmitter portion of the Air Traffic Control Radar Beacon System (ATCRBS) which automatically receives radio signals from interrogators on the ground, and selectively replies with a specific reply pulse or pulse group only to those interrogations being received on the mode to which it is set to respond.

SeeINTERROGATOR

SeeICAO term TRANSPONDER

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The Federal Aviation Administrator or any person to whom he/she has delegated his/her authority in the matter concerned.

SeeICAO term AUTOMATIC DEPENDENT SURVEILLANCE

SeeAUTOMATIC DEPENDENT SURVEILLANCE-BROADCAST

A defined area on land or water (including any buildings, installations and equipment) intended to be used either wholly or in part for the arrival, departure, and movement of aircraft.

A grouping of aircraft based on a speed of 1.3 times the stall speed in the landing configuration at maximum gross landing weight. An aircraft must fit in only one category. If it is necessary to maneuver at speeds in excess of the upper limit of a speed range for a category, the minimums for the category for that speed must be used. For example, an aircraft which falls in Category A, but is circling to land at a speed in excess of 91 knots, must use the approach Category B minimums when circling to land. The categories are as follows:

1. Category A- Speed less than 91 knots.
2. Category B- Speed 91 knots or more but less than 121 knots.
3. Category C- Speed 121 knots or more but less than 141 knots.
4. Category D- Speed 141 knots or more but less than 166 knots.
5. Category E- Speed 166 knots or more.

Refer to14 CFR part 97

A concise description of an occurrence or expected occurrence of specified en route weather phenomena that may affect the safety of aircraft operations, but at intensities lower than those that require the issuance of a SIGMET. An AIRMET may be issued when any of the following weather phenomena are occurring or expected to occur:

1. Moderate turbulence
2. Low-level windshear
3. Strong surface winds greater than 30 knots
4. Moderate icing
5. Freezing level
6. Mountain obscuration
7. IFR

SeeCONVECTIVE SIGMET

SeeCWA

SeeGRAPHICAL AIRMEN'S METEOROLOGICAL INFORMATION

SeeSAW

SeeSIGMET

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A notification to a position that there is an aircraft‐to‐aircraft or aircraft‐to‐airspace conflict, as detected by Automated Problem Detection (APD).

The time an aircraft touches down on arrival.

Directives issued by air traffic control for the purpose of requiring a pilot to take specific actions; e.g., “Turn left heading two five zero,” “Go around,” “Clear the runway.”

Refer to14 CFR part 91

BROADCAST (ADS‐B)- A surveillance system in which an aircraft or vehicle to be detected is fitted with cooperative equipment in the form of a data link transmitter. The aircraft or vehicle periodically broadcasts its GNSS-derived position and other required information such as identity and velocity, which is then received by a ground-based or space-based receiver for processing and display at an air traffic control facility, as well as by suitably equipped aircraft.

SeeAUTOMATIC DEPENDENT SURVEILLANCE-BROADCAST IN

SeeAUTOMATIC DEPENDENT SURVEILLANCE-BROADCAST OUT

SeeCOOPERATIVE SURVEILLANCE

SeeGLOBAL POSITIONING SYSTEM

SeeSPACE-BASED ADS-B

The horizontal direction to or from any point, usually measured clockwise from true north, magnetic north, or some other reference point through 360 degrees.

SeeNONDIRECTIONAL BEACON

Transmission of information for which an acknowledgement is not expected.

SeeICAO term BROADCAST

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.”

SeeICAO term CEILING

A series of civil/military flight information publications issued by FAA every 56 days consisting of the Chart Supplement U.S., Chart Supplement Alaska, and Chart Supplement Pacific.

SeeAIR TRAFFIC CONTROL SPECIALIST

A weather advisory concerning convective weather significant to the safety of all aircraft. Convective SIGMETs are issued for tornadoes, lines of thunderstorms, embedded thunderstorms of any intensity level, areas of thunderstorms greater than or equal to VIP level 4 with an area coverage of ⁴/₁₀ (40%) or more, and hail ³/₄ inch or greater.

SeeAIRMET

SeeCWA

SeeGRAPHICAL AIRMEN'S METEOROLOGICAL INFORMATION

SeeSAW

SeeSIGMET

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With respect to the operation of aircraft, means the height at which a decision must be made during an ILS or PAR instrument approach to either continue the approach or to execute a missed approach.

SeeICAO term DECISION ALTITUDE/DECISION HEIGHT

1. True- A predetermined desired course direction to be followed (measured in degrees from true north).
2. Magnetic- A predetermined desired course direction to be followed (measured in degrees from local magnetic north).

1. A departure from a current clearance, such as an off course maneuver to avoid weather or turbulence.
2. Where specifically authorized in the CFRs and requested by the pilot, ATC may permit pilots to deviate from certain regulations.

A condition of being threatened by serious and/or imminent danger and of requiring immediate assistance.

SeeTRAFFIC PATTERN

SeeEMERGENCY LOCATOR TRANSMITTER

A radio transmitter attached to the aircraft structure which operates from its own power source on 121.5 MHz and 243.0 MHz. It aids in locating downed aircraft by radiating a downward sweeping audio tone, 2‐4 times per second. It is designed to function without human action after an accident.

Refer to14 CFR part 91

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SeeESTIMATED TIME OF ARRIVAL

SeeSEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE

A flight for the purpose of:

1. Investigating the operation/flight characteristics of an aircraft or aircraft component.
2. Evaluating an applicant for a pilot certificate or rating.

SeeFLIGHT MANAGEMENT SYSTEM

That portion of civil aviation that does not include scheduled or unscheduled air carriers or commercial space operations.

SeeICAO term GENERAL AVIATION

SeeMINIMUM DESCENT ALTITUDE

The lowest altitude, expressed in feet above mean sea level, to which descent is authorized on final approach or during circle‐to‐land maneuvering in execution of a standard instrument approach procedure where no electronic glideslope is provided.

SeeNONPRECISION APPROACH PROCEDURE

The letter or number assigned to a specific pulse spacing of radio signals transmitted or received by ground interrogator or airborne transponder components of the Air Traffic Control Radar Beacon System (ATCRBS). Mode A (military Mode 3) and Mode C (altitude reporting) are used in air traffic control.

SeeINTERROGATOR

SeeRADAR

SeeTRANSPONDER

SeeICAO term MODE

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Mountain waves occur when air is being blown over a mountain range or even the ridge of a sharp bluff area. As the air hits the upwind side of the range, it starts to climb, thus creating what is generally a smooth updraft which turns into a turbulent downdraft as the air passes the crest of the ridge. Mountain waves can cause significant fluctuations in airspeed and altitude with or without associated turbulence.

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SeePILOT WEATHER REPORT

The separation of all air traffic within designated airspace by air traffic control.

Any or all forms of water particles (rain, sleet, hail, or snow) that fall from the atmosphere and reach the surface.

A magnetic bearing extending from a VOR/VORTAC/TACAN navigation facility.

When weather conditions permit, pilots operating IFR or VFR are required to observe and maneuver to avoid other aircraft. Right‐of‐way rules are contained in 14 CFR part 91.

In air traffic control, the spacing of aircraft to achieve their safe and orderly movement in flight and while landing and taking off.

SeeSEPARATION MINIMA

SeeICAO term SEPARATION

SeeSIGMET

The beginning of that portion of the runway usable for landing.

SeeAIRPORT LIGHTING

SeeDISPLACED THRESHOLD

Advisories issued to alert pilots to other known or observed air traffic which may be in such proximity to the position or intended route of flight of their aircraft to warrant their attention. Such advisories may be based on:

1. Visual observation.
2. Observation of radar identified and nonidentified aircraft targets on an ATC radar display, or
3. Verbal reports from pilots or other facilities.

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Meteorological conditions expressed in terms of visibility, distance from cloud, and ceiling equal to or better than specified minima.

SeeINSTRUMENT FLIGHT RULES

SeeINSTRUMENT METEOROLOGICAL CONDITIONS

SeeVISUAL FLIGHT RULES

A predetermined geographical position used for route/instrument approach definition, progress reports, published VFR routes, visual reporting points or points for transitioning and/or circumnavigating controlled and/or special use airspace, that is defined relative to a VORTAC station or in terms of latitude/longitude coordinates.