Table 3.5. Clear Zones. (See note 1.)
Centered on the extended runway centerline. All
914.4 m (3000 ft)
items sited within this area must be frangible (see
1. Applicable to aviation facilities installations of the Military Departments in the United States, its territories,
trusts, and possessions. For military facilities overseas, other than in locations designated, apply to the
maximum practical extent.
2. For the definition of runway end refer to the glossary.
3. Essential NAVAID structure exceptions are discussed in Attachment 14.
4. Airfield and heliport imaginary surfaces and safe wingtip clearance dimensions are direct conversions from
inch-pound to SI units.
5. Metric units apply to new airfield construction, and where practical, to modifications to existing airfields and
heliports, as discussed in Paragraph 1.4.4.
Table 3.6. Accident Potential Zones (APZ).
1,524.00 m APZ I starts at the end of the Clear Zone, and is
[5,000 ft] centered and measured on the extended centerline.
Modifications will be considered if:
- The runway is infrequently used.
- Prevailing wind conditions are such that a large
percentage (that is, over 80 percent) of the
operations are in one direction.
- Local accident history indicates consideration of
- Most aircraft do not overfly an APZ area as
defined here during normal flight operations
(modifications may be made to alter these zones
and adjust them to conform to the line of flight).
- Other unusual conditions exist.
Air Force, Navy, and Marine Corps airfields.