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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




Hydroplaning. A condition that exists when landing on a
surface with standing water deeper than the tread depth of
the tires. When the brakes are applied, there is a possibility
that the brake will lock up and the tire will ride on the
surface of the water, much like a water ski. When the tires
are hydroplaning, directional control and braking action
are virtually impossible. An effective anti-skid system can
minimize the effects of hydroplaning.

Hypemic hypoxia. A type of hypoxia that is a result of
oxygen deficiency in the blood, rather than a lack of inhaled
oxygen. It can be caused by a variety of factors. Hypemic
means "not enough blood."

Hyperventilation. Occurs when an individual is experiencing
emotional stress, fright, or pain, and the breathing rate and
depth increase, although the carbon dioxide level in the
blood is already at a reduced level. The result is an excessive
loss of carbon dioxide from the body, which can lead to
unconsciousness due to the respiratory system's overriding
mechanism to regain control of breathing.

Hypoxia. A state of oxygen deficiency in the body sufficient
to impair functions of the brain and other organs.

Hypoxic hypoxia. This type of hypoxia is a result of
insufficient oxygen available to the lungs. A decrease of
oxygen molecules at sufficient pressure can lead to hypoxic

IAF. See initial approach fix.

IAP. See instrument approach procedures.

IAS. See indicated airspeed.

ICAO. See International Civil Aviation Organization.

Ident. Air Traffic Control request for a pilot to push
the button on the transponder to identify return on the
controller's scope.

IFR. See instrument flight rules.

ILS. See instrument landing system.

ILS categories. Categories of instrument approach
procedures allowed at airports equipped with the following
types of instrument landing systems:

ILS Category I: Provides for approach to a height
above touchdown of not less than 200 feet, and with
runway visual range of not less than 1,800 feet

ILS Category II: Provides for approach to a height
above touchdown of not less than 100 feet and with
runway visual range of not less than 1,200 feet.

ILS Category IIIA: Provides for approach without
a decision height minimum and with runway visual
range of not less than 700 feet.

ILS Category IIIB: Provides for approach without
a decision height minimum and with runway visual
range of not less than 150 feet.

ILS Category IIIC: Provides for approach without a
decision height minimum and without runway visual
range minimum.

IMC. See instrument meteorological conditions.
Inclinometer. An instrument consisting of a curved glass
tube, housing a glass ball, and damped with a fluid similar
to kerosene. It may be used to indicate inclination, as a level,
or, as used in the turn indicators, to show the relationship
between gravity and centrifugal force in a turn.

Indicated airspeed (IAS). Shown on the dial of the
instrument airspeed indicator on an aircraft. Indicated
airspeed (IAS) is the airspeed indicator reading uncorrected
for instrument, position, and other errors. Indicated airspeed
means the speed of an aircraft as shown on its pitot static
airspeed indicator calibrated to reflect standard atmosphere
adiabatic compressible flow at sea level uncorrected for
airspeed system errors. Calibrated airspeed (CAS) is IAS
corrected for instrument errors, position error (due to
incorrect pressure at the static port) and installation errors.

Indicated altitude. The altitude read directly from the
altimeter (uncorrected) when it is set to the current altimeter

Indirect indication. A reflection of aircraft pitch-and-bank
attitude by instruments other than the attitude indicator.

Induced drag. Drag caused by the same factors that produce
lift; its amount varies inversely with airspeed. As airspeed
decreases, the angle of attack must increase, in turn increasing
induced drag.

Induction icing. A type of ice in the induction system that
reduces the amount of air available for combustion. The most
commonly found induction icing is carburetor icing.

Inertial navigation system (INS). A computer-based
navigation system that tracks the movement of an aircraft
via signals produced by onboard accelerometers. The initial
location of the aircraft is entered into the computer, and all
subsequent movement of the aircraft is sensed and used to
keep the position updated. An INS does not require any inputs
from outside signals.