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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




Localizer-type directional aid (LDA). A NAVAID used
for nonprecision instrument approaches with utility and
accuracy comparable to a localizer but which is not a part
of a complete ILS and is not aligned with the runway. Some

LDAs are equipped with a glideslope.

Locator middle marker (LMM). Nondirectional radio
beacon (NDB) compass locator, collocated with a middle
marker (MM).

Locator outer marker (LOM). NDB compass locator,
collocated with an outer marker (OM).

LOM. See locator outer marker.

Longitude. Measurement east or west of the Prime Meridian
in degrees, minutes, and seconds. The Prime Meridian is 0°
longitude and runs through Greenwich, England. Lines of
longitude are also referred to as meridians.

Longitudinal axis. An imaginary line through an aircraft
from nose to tail, passing through its center of gravity. The
longitudinal axis is also called the roll axis of the aircraft.
Movement of the ailerons rotates an airplane about its
longitudinal axis.

Longitudinal stability (pitching). Stability about the lateral
axis. A desirable characteristic of an airplane whereby it tends
to return to its trimmed angle of attack after displacement.

Long range navigation (LORAN). An electronic
navigational system by which hyperbolic lines of position
are determined by measuring the difference in the time of
reception of synchronized pulse signals from two .xed
transmitters. LORAN-A operates in the 1750–1950 kHz
frequency band. LORAN-C and -D operate in the 100–110
kHz frequency band.

LORAN. See long range navigation.

LORAN-C. A radio navigation system that utilizes master
and slave stations transmitting timed pulses. The time
difference in reception of pulses from several stations
establishes a hyperbolic line of position, which can be
identified on a LORAN chart. A fix in position is obtained
by utilizing signals from two or more stations.

Low or medium frequency. A frequency range between
190 and 535 kHz with the medium frequency above 300
kHz. Generally associated with nondirectional beacons
transmitting a continuous carrier with either a 400 or 1,020
Hz modulation.

Lubber line. The reference line used in a magnetic compass
or heading indicator.

MAA. See maximum authorized altitude.

MAC. See mean aerodynamic chord.

Mach number. The ratio of the true airspeed of the aircraft
to the speed of sound in the same atmospheric conditions,
named in honor of Ernst Mach, late 19th century physicist.

Mach meter. The instrument that displays the ratio of the
speed of sound to the true airspeed an aircraft is flying.

Magnetic bearing (MB). The direction to or from a radio
transmitting station measured relative to magnetic north.

Magnetic compass. A device for determining direction
measured from magnetic north.

Magnetic dip. A vertical attraction between a compass
needle and the magnetic poles. The closer the aircraft is to a
pole, the more severe the effect.

Magnetic heading (MH). The direction an aircraft is pointed
with respect to magnetic north.

Magneto. A self-contained, engine-driven unit that supplies
electrical current to the spark plugs; completely independent
of the airplane's electrical system. Normally there are two
magnetos per engine.

Magnus effect. Lifting force produced when a rotating
cylinder produces a pressure differential. This is the same
effect that makes a baseball curve or a golf ball slice.

Mandatory altitude. An altitude depicted on an instrument
approach chart with the altitude value both underscored and
overscored. Aircraft are required to maintain altitude at the
depicted value.

Mandatory block altitude. An altitude depicted on an
instrument approach chart with two underscored and
overscored altitude values between which aircraft are
required to maintain altitude.

Maneuverability. Ability of an aircraft to change directions
along a flightpath and withstand the stresses imposed upon

Maneuvering speed (VA). The
design maneuvering speed. Operating at or below design
maneuvering speed does not provide structural protection against
multiple full control inputs in one axis or full control
inputs in more than one axis at the same time.