Landing Rollout--Distances covered in stopping the aircraft, when loaded to maximum landing
weight, following touchdown using standard operation and braking procedures on a hard, dry-surfaced,
level runway with no wind.
Landing Strip--That portion of an airfield that includes the landing area, the end zones, and the
shoulder areas. Also known as a flight strip.
Landside Facilities--Landside facilities are facilities not associated with the movement and parking of
aircraft but are required for the facilities' mission. These include aircraft maintenance areas, aviation
support areas, fuel storage and dispensing, explosives and munitions areas and vehicular needs.
Large Transport Aircraft--A transport aircraft with a wing span of 33.5 m [110 ft] or greater.
Light Bar--A set of lights arranged in a row perpendicular to the light system centerline.
Line Vehicle--Any vehicle used on the landing strip, such as a crash fire truck or tow tractor.
Localizer--A directional radio beacon which provides to an aircraft an indication of its lateral position
relative to a predetermined final approach course.
Localizer Type Directional Aid (LDA)--A NAVAID used for nonprecision instrument approaches
with utility and accuracy comparable to a localizer but which is not part of a complete ILS. The LDA is
not aligned with the runway. The alignment is greater than 3 degrees (3) and less than 30 degrees (30)
from the runway centerline.
Magnetic North--The direction indicated by the north-seeking pole of a freely suspended magnetic
needle, influenced only by the earth's magnetic field.
Magnetic Variation--At a given place and time, the horizontal angle between the true north and
magnetic north measured east or west according to whether magnetic north lies east or west of true
Magnetically Quiet Zone--A location where magnetic equipment, such as a compass, is only affected
by the earth's magnetic forces.
Non-Precision Approach--An approach flown by reference to electronic navigation aids in which
glide slope information is not available.
Non-Instrument Runway--A runway intended for operating aircraft under visual flight rules.
Obstacle--An existing object, 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 operations.
Obstacle Clearance--The vertical distance between the lowest authorized flight altitude and a
prescribed surface within a specified area.
Obstruction--A natural or man-made object that violates airfield or heliport clearances, or projects into
imaginary airspace surfaces. Navy and Marine Corps see NAVFAC P-80.3.
Overrun Area--An area the width of the runway plus paved shoulders extending from the end of the
runway to the outer limit of the end zone. This portion is a prolongation of the runway which is the
Parking, Aircraft Undergoing Maintenance--Apron parking space is provided for parking aircraft
which must undergo maintenance.