| Home | Privacy | Contact |


| First | Previous | Next | Last |

Pilot's Handbook of Aeronautical Knowledge



Table of Contents

Chapter 1, Introduction To Flying
Chapter 2, Aircraft Structure
Chapter 3, Principles of Flight
Chapter 4, Aerodynamics of Flight
Chapter 5, Flight Controls
Chapter 6, Aircraft Systems
Chapter 7, Flight Instruments
Chapter 8, Flight Manuals and Other Documents
Chapter 9, Weight and Balance
Chapter 10, Aircraft Performance
Chapter 11, Weather Theory
Chapter 12, Aviation Weather Services
Chapter 13, Airport Operation
Chapter 14, Airspace
Chapter 15, Navigation
Chapter 16, Aeromedical Factors
Chapter 17, Aeronautical Decision Making




VLO. Landing gear operating speed. The maximum speed for
extending or retracting the landing gear if using an airplane
equipped with retractable landing gear.

VMC. Minimum control airspeed. This is the minimum
flight speed at which a light, twin-engine airplane can be
satisfactorily controlled when an engine suddenly becomes
inoperative and the remaining engine is at takeoff power.

VMC. See visual meteorological conditions.

VNE. The never-exceed speed. Operating above this speed is
prohibited since it may result in damage or structural failure.
The red line on the airspeed indicator.

VNO. The maximum structural cruising speed. Do not exceed
this speed except in smooth air. The upper limit of the green

VOR. See very-high frequency omnidirectional range.

VORTAC. A facility consisting of two components, VOR
and TACAN, which provides three individual services: VOR
azimuth, TACAN azimuth, and TACAN distance (DME)
at one site.

VOR test facility (VOT). A ground facility which emits a
test signal to check VOR receiver accuracy. Some VOTs are
available to the user while airborne, while others are limited
to ground use only.

VOT. See VOR test facility.

VSI. See vertical speed indicator.

VS0. The stalling speed or the minimum steady flight speed
in the landing configuration. In small airplanes, this is the
power-off stall speed at the maximum landing weight in the
landing configuration (gear and flaps down). The lower limit
of the white arc.

VS1. The stalling speed or the minimum steady flight speed
obtained in aspecified configuration. For most airplanes, this
is the power-off stall speed at the maximum takeoff weight
in the clean configuration (gear up, if retractable, and flaps
up). The lower limit of the green arc.

V-tail. A design which utilizes two slanted tail surfaces to
perform the same functions as the surfaces of a conventional
elevator and rudder configuration. The fixed surfaces act as
both horizontal and vertical stabilizers.

VX. Best angle-of-climb speed. The airspeed at which an
airplane gains the greatest amount of altitude in a given
distance. It is used during a short-field takeoff to clear an

VY. Best rate-of-climb speed. This airspeed provides the
most altitude gain in a given period of time.

VYSE. Best rate-of-climb speed with one engine inoperative.
This airspeed provides the most altitude gain in a given
period of time in a light, twin-engine airplane following an
engine failure.

WAAS. See wide area augmentation system.
Wake turbulence. Wingtip vortices that are created when
an airplane generates lift. When an airplane generates lift,
air spills over the wingtips from the high pressure areas
below the wings to the low pressure areas above them. This
flow causes rapidly rotating whirlpools of air called wingtip
vortices or wake turbulence.

Warm front. The boundary area formed when a warm air
mass contacts and .ows over a colder air mass. Warm fronts
cause low ceilings and rain.

Warning area. An area containing hazards to any aircraft
not participating in the activities being conducted in the
area. Warning areas may contain intensive military training,
gunnery exercises, or special weapons testing.

WARP. See weather and radar processing.

Waste gate. A controllable valve in the tailpipe of an aircraft
reciprocating engine equipped with a turbocharger. The valve
is controlled to vary the amount of exhaust gases forced
through the turbocharger turbine.

Waypoint. A designated geographical location used for route
de.nition or progress-reporting purposes and is de.ned in
terms of latitude/longitude coordinates.

WCA. See wind correction angle.

Weather and radar processor (WARP). A device that
provides real-time, accurate, predictive, and strategic weather
information presented in an integrated manner in the National
Airspace System (NAS).

Weather depiction chart. Details surface conditions as
derived from METAR and other surface observations.