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V
VASI-
(See VISUAL APPROACH SLOPE INDICATOR.)
VCOA-
(See VISUAL CLIMB OVER AIRPORT.)
VDF-
(See DIRECTION FINDER.)
VDP-
(See VISUAL DESCENT POINT.)
VECTOR- A heading issued to an aircraft to
provide navigational guidance by radar.
(See ICAO term RADAR VECTORING.)
VERIFY- Request confirmation of
information; e.g., “verify assigned altitude.”
VERIFY SPECIFIC DIRECTION OF TAKEOFF
(OR TURNS AFTER TAKEOFF)- Used by ATC to ascertain an aircraft's
direction of takeoff and/or direction of turn after takeoff. It is normally used
for IFR departures from an airport not having a control tower. When direct
communication with the pilot is not possible, the request and information may be
relayed through an FSS, dispatcher, or by other means.
(See IFR TAKEOFF MINIMUMS AND DEPARTURE
PROCEDURES.)
VERTEX- The last fix adapted on the arrival
speed segments. Normally, it will be the outer marker of the runway in use.
However, it may be the actual threshold or other suitable common point on the
approach path for the particular runway configuration.
VERTEX TIME OF ARRIVAL- A calculated time of
aircraft arrival over the adapted vertex for the runway configuration in use.
The time is calculated via the optimum flight path using adapted speed segments.
VERTICAL NAVIGATION (VNAV)– A function of
area navigation (RNAV) equipment which calculates, displays, and provides
vertical guidance to a profile or path.
VERTICAL SEPARATION- Separation between
aircraft expressed in units of vertical distance.
(See SEPARATION.)
VERTICAL TAKEOFF AND LANDING AIRCRAFT-
Aircraft capable of vertical climbs and/or descents and of using very short
runways or small areas for takeoff and landings. These aircraft include, but are
not limited to, helicopters.
(See SHORT TAKEOFF AND LANDING AIRCRAFT.)
VERY HIGH FREQUENCY- The frequency band
between 30 and 300 MHz. Portions of this band, 108 to 118 MHz, are used for
certain NAVAIDs; 118 to 136 MHz are used for civil air/ground voice
communications. Other frequencies in this band are used for purposes not related
to air traffic control.
VERY HIGH FREQUENCY OMNIDIRECTIONAL RANGE
STATION-
(See VOR.)
VERY LOW FREQUENCY- The frequency band
between 3 and 30 kHz.
VFR-
(See VISUAL FLIGHT RULES.)
VFR AIRCRAFT- An aircraft conducting flight
in accordance with visual flight rules.
(See VISUAL FLIGHT RULES.)
VFR CONDITIONS- Weather
conditions equal to or better than the minimum for flight under visual flight
rules. The term may be used as an ATC clearance/instruction only when:
a. An IFR aircraft requests a
climb/descent in VFR conditions.
b. The clearance will result in noise
abatement benefits where part of the IFR departure route does not conform to an
FAA approved noise abatement route or altitude.
c. A pilot has requested a practice
instrument approach and is not on an IFR flight plan.
Note: All pilots receiving this authorization
must comply with the VFR visibility and distance from cloud criteria in 14 CFR
Part 91. Use of the term does not relieve controllers of their responsibility to
separate aircraft in Class B and Class C airspace or TRSAs as required by FAAO JO
7110.65. When used as an ATC clearance/instruction, the term may be abbreviated
“VFR;” e.g., “MAINTAIN VFR,” “CLIMB/DESCEND VFR,” etc.
VFR FLIGHT-
(See VFR AIRCRAFT.)
VFR MILITARY TRAINING ROUTES- Routes used by
the Department of Defense and associated Reserve and Air Guard units for the
purpose of conducting low‐altitude navigation and tactical training under VFR
below 10,000 feet MSL at airspeeds in excess of 250 knots IAS.
VFR NOT RECOMMENDED- An
advisory provided by a flight service station to a pilot during a preflight or
inflight weather briefing that flight under visual flight rules is not
recommended. To be given when the current and/or forecast weather conditions are
at or below VFR minimums. It does not abrogate the pilot's authority to make
his/her own decision.
VFR‐ON‐TOP- ATC authorization
for an IFR aircraft to operate in VFR conditions at any appropriate VFR altitude
(as specified in 14 CFR and as restricted by ATC). A pilot receiving this
authorization must comply with the VFR visibility, distance from cloud criteria,
and the minimum IFR altitudes specified in 14 CFR Part 91. The use of this term
does not relieve controllers of their responsibility to separate aircraft in
Class B and Class C airspace or TRSAs as required by FAAO JO 7110.65.
VFR TERMINAL AREA CHARTS-
(See AERONAUTICAL CHART.)
VFR WAYPOINT-
(See WAYPOINT.)
VHF-
(See VERY HIGH FREQUENCY.)
VHF OMNIDIRECTIONAL RANGE/TACTICAL AIR
NAVIGATION-
(See VORTAC.)
VIDEO MAP- An electronically displayed map on
the radar display that may depict data such as airports, heliports, runway
centerline extensions, hospital emergency landing areas, NAVAIDs and fixes,
reporting points, airway/route centerlines, boundaries, handoff points, special
use tracks, obstructions, prominent geographic features, map alignment
indicators, range accuracy marks, minimum vectoring altitudes.
VISIBILITY- 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 to 14 CFR Part 91.)
(Refer to AIM.)
a. 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.
b. Ground Visibility- Prevailing
horizontal visibility near the earth's surface as reported by the United States
National Weather Service or an accredited observer.
c. Prevailing Visibility- The greatest
horizontal visibility equaled or exceeded throughout at least half the horizon
circle which need not necessarily be continuous.
d. Runway Visibility Value (RVV)- The
visibility determined for a particular runway by a transmissometer. A meter
provides a continuous indication of the visibility (reported in miles or
fractions of miles) for the runway. RVV is used in lieu of prevailing visibility
in determining minimums for a particular runway.
e. 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 is used in lieu of RVV and/or prevailing
visibility in determining minimums for a particular runway.
1. Touchdown RVR- The RVR
visibility readout values obtained from RVR equipment serving the runway
touchdown zone.
2. Mid-RVR- The RVR readout
values obtained from RVR equipment located midfield of the runway.
3. Rollout RVR-
The RVR readout values obtained from RVR equipment located nearest the rollout
end of the runway.
(See ICAO term FLIGHT VISIBILITY.)
(See ICAO term GROUND VISIBILITY.)
(See ICAO term RUNWAY VISUAL RANGE.)
(See ICAO term VISIBILITY.)
VISIBILITY [ICAO]- 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.
a. Flight Visibility-The visibility
forward from the cockpit of an aircraft in flight.
b. Ground Visibility-The visibility at
an aerodrome as reported by an accredited observer.
c. Runway Visual Range [RVR]-The range
over which the pilot of an aircraft on the centerline of a runway can see the
runway surface markings or the lights delineating the runway or identifying its
centerline.
VISUAL APPROACH- An approach conducted on an
instrument flight rules (IFR) flight plan which authorizes the pilot to proceed
visually and clear of clouds to the airport. The pilot must, at all times, have
either the airport or the preceding aircraft in sight. This approach must be
authorized and under the control of the appropriate air traffic control
facility. Reported weather at the airport must be ceiling at or above 1,000 feet
and visibility of 3 miles or greater.
(See ICAO term VISUAL APPROACH.)
VISUAL APPROACH [ICAO]- An approach by an IFR
flight when either part or all of an instrument approach procedure is not
completed and the approach is executed in visual reference to terrain.
VISUAL APPROACH SLOPE INDICATOR-
(See AIRPORT LIGHTING.)
VISUAL CLIMB OVER AIRPORT (VCOA)- A departure
option for an IFR aircraft, operating in visual meteorological conditions equal
to or greater than the specified visibility and ceiling, to visually conduct
climbing turns over the airport to the published "climb-to" altitude from which
to proceed with the instrument portion of the departure. VCOA procedures are
developed to avoid obstacles greater than 3 statute miles from the departure end
of the runway as an alternative to complying with climb gradients greater than
200 feet per nautical mile. These procedures are published in the `Take-Off
Minimums and (Obstacle) Departure Procedures' section of the Terminal Procedures
Publications.
(See AIM.)
VISUAL DESCENT POINT- A defined point on the
final approach course of a nonprecision straight-in approach procedure from
which normal descent from the MDA to the runway touchdown point may be
commenced, provided the approach threshold of that runway, or approach lights,
or other markings identifiable with the approach end of that runway are clearly
visible to the pilot.
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.
(See INSTRUMENT FLIGHT RULES.)
(See INSTRUMENT METEOROLOGICAL CONDITIONS.)
(See VISUAL METEOROLOGICAL CONDITIONS.)
(Refer to 14 CFR Part 91.)
(Refer to AIM.)
VISUAL HOLDING- The holding of aircraft at
selected, prominent geographical fixes which can be easily recognized from the
air.
(See HOLDING FIX.)
VISUAL METEOROLOGICAL CONDITIONS-
Meteorological conditions expressed in terms of visibility, distance from cloud,
and ceiling equal to or better than specified minima.
(See INSTRUMENT FLIGHT RULES.)
(See INSTRUMENT METEOROLOGICAL CONDITIONS.)
(See VISUAL FLIGHT RULES.)
VISUAL SEGMENT-
(See PUBLISHED INSTRUMENT APPROACH PROCEDURE
VISUAL SEGMENT.)
VISUAL SEPARATION- A means
employed by ATC to separate aircraft in terminal areas and en route airspace in
the NAS. There are two ways to effect this separation:
a. The tower controller sees the
aircraft involved and issues instructions, as necessary, to ensure that the
aircraft avoid each other.
b. A pilot sees the other aircraft
involved and upon instructions from the controller provides his/her own
separation by maneuvering his/her aircraft as necessary to avoid it. This may
involve following another aircraft or keeping it in sight until it is no longer
a factor.
(See SEE AND AVOID.)
(Refer to 14 CFR Part 91.)
VLF-
(See VERY LOW FREQUENCY.)
VMC-
(See VISUAL METEOROLOGICAL CONDITIONS.)
VOICE SWITCHING AND CONTROL SYSTEM- The VSCS
is a computer controlled switching system that provides air traffic controllers
with all voice circuits (air to ground and ground to ground) necessary for air
traffic control.
(See VOICE SWITCHING AND CONTROL SYSTEM.)
(Refer to AIM.)
VOR- A ground-based electronic navigation aid
transmitting very high frequency navigation signals, 360 degrees in azimuth,
oriented from magnetic north. Used as the basis for navigation in the National
Airspace System. The VOR periodically identifies itself by Morse Code and may
have an additional voice identification feature. Voice features may be used by
ATC or FSS for transmitting instructions/information to pilots.
(See NAVIGATIONAL AID.)
(Refer to AIM.)
VOR TEST SIGNAL-
(See VOT.)
VORTAC- A navigation aid providing VOR
azimuth, TACAN azimuth, and TACAN distance measuring equipment (DME) at one
site.
(See DISTANCE MEASURING EQUIPMENT.)
(See NAVIGATIONAL AID.)
(See TACAN.)
(See VOR.)
(Refer to AIM.)
VORTICES- Circular patterns of air created by
the movement of an airfoil through the air when generating lift. As an airfoil
moves through the atmosphere in sustained flight, an area of area of low
pressure is created above it. The air flowing from the high pressure area to the
low pressure area around and about the tips of the airfoil tends to roll up into
two rapidly rotating vortices, cylindrical in shape. These vortices are the most
predominant parts of aircraft wake turbulence and their rotational force is
dependent upon the wing loading, gross weight, and speed of the generating
aircraft. The vortices from medium to heavy aircraft can be of extremely high
velocity and hazardous to smaller aircraft.
(See AIRCRAFT CLASSES.)
(See WAKE TURBULENCE.)
(Refer to AIM.)
VOT- A ground facility which emits a test
signal to check VOR receiver accuracy. Some VOTs are available to the user while
airborne, and others are limited to ground use only.
(See AIRPORT/FACILITY DIRECTORY.)
(Refer to 14 CFR Part 91.)
(Refer to AIM.)
VR-
(See VFR MILITARY TRAINING ROUTES.)
VSCS-
(See VOICE SWITCHING AND CONTROL SYSTEM.)
VTA-
(See VERTEX TIME OF ARRIVAL.)
VTOL AIRCRAFT-
(See VERTICAL TAKEOFF AND LANDING AIRCRAFT.)
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