5.21 Safety (SA)
Accident Potential Zone II. The Accident Potential Zone II (APZ II) is an area
that begins at the end of each APZ I and extends an additional 7,000 feet long
by 3,000 feet wide.
Safety zones are areas in which development should be more restrictive, in
terms of use and concentrations of people, due to the higher risks to public
safety. Issues to consider include aircraft accident potential zones, weapons
firing range safety zones, explosive safety zones, and bird / wildlife aircraft
strike hazards.
This APZ can also be curved as the flight tracks are considered in designating
this APZ. Again, the accident potential in this area reduces further, and with
this, some additional development types are allowed.
Military installations often engage in activities or contain facilities that, due to
public safety concerns, require special consideration by local jurisdictions
when evaluating compatibility. It is important to regulate land use near
military airfields in order to minimize damage from potential aircraft
accidents and to reduce air navigation hazards. To help mitigate potential
issues, the DOD has delineated Clear Zones (CZ) and APZ in the vicinity of
airfield runways. The APZ is usually divided into APZ I and APZ II. Each zone
was developed based on the statistical review of aircraft accidents. Studies
show that most mishaps occur on or near the runway, predominately along
its extended centerline.
Area Operations Area. The Area Operations Area (AOA) is an area that
encompasses the entire airport's approach or departure airspace including
the circling space.
Bird / Wildlife Aircraft Strike Hazard. BASH refers to the likely occurrence for a
collision between an airborne animal (usually a bird) and a human‐made
vehicle, particularly aircraft.
BASH Relevancy Area. The BASH Relevancy Area is a 5‐statute mile area from
the airport operational area, including the runway. This area has been
determined by the FAA as an area where BASH incidences are likely to occur
due to the types of flying operations that occur near the airfield, such
operations are typically at slower speeds and lower altitudes making the
conditions for BASH opportune.
Key Terms
Accident Potential Zone I (APZ I). Accident Potential Zone I (APZ I) is an area
beginning at the end of each clear zone (see definition below) and continuing
out to a length of 5,000 feet long by 3,000 feet wide. APZ I can follow a
curved shape to reflect the predominant flight tracks, and can even split to
reflect differences in standard approaches/departures and closed pattern
tracks. This area has a lower potential for accidents and therefore has less
restrictive development restrictions recommended.
Clear Zone. The CZ is the area that has the highest statistical potential of an
aircraft incident (but again, a very low probability). As the name reflects, this
area should be kept clear of all structures, including fences. A CZ begins at
the physical end of a runway and extends outward, typically covering an area
that is 3,000 feet wide by 3,000 feet long.
Background Report
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