Pilot/Controller Glossary

to monitor certain non-radar approaches, but is primarily used to conduct a precision instrument approach (PAR)
wherein the controller issues guidance instructions to the pilot based on the aircraft"s position in relation to the
final approach course (azimuth), the glidepath (elevation), and the distance (range) from the touchdown point
on the runway as displayed on the radar scope.
(See GLIDEPATH.)
(See PAR.)
(See ICAO term PRECISION APPROACH RADAR.)
(Refer to AIM.)

PRECISION APPROACH RADAR [ICAO]- Primary radar equipment used to determine the position of an
aircraft during final approach, in terms of lateral and vertical deviations relative to a nominal approach path, and
in range relative to touchdown.
PRECISION OBSTACLE FREE ZONE (POFZ)- An 800 foot wide by 200 foot long area centered on the
runway centerline adjacent to the threshold designed to protect aircraft flying precision approaches from ground
vehicles and other aircraft when ceiling is less than 250 feet or visibility is less than 3/4 statute mile (or runway
visual range below 4,000 feet.)
PRECISION RUNWAY MONITOR (PRM) SYSTEM- Provides air traffic controllers monitoring the NTZ
during simultaneous close parallel PRM approaches with precision, high update rate secondary surveillance
data. The high update rate surveillance sensor component of the PRM system is only required for specific runway
or approach course separation. The high resolution color monitoring display, Final Monitor Aid (FMA) of the
PRM system, or other FMA with the same capability, presents NTZ surveillance track data to controllers along
with detailed maps depicting approaches and no transgression zone and is required for all simultaneous close
parallel PRM NTZ monitoring operations.
(Refer to AIM)

PREDICTIVE WIND SHEAR ALERT SYSTEM (PWS)- A self-contained system used on board some aircraft
to alert the flight crew to the presence of a potential wind shear. PWS systems typically monitor 3 miles ahead
and 25 degrees left and right of the aircraft"s heading at or below 1200" AGL. Departing flights may receive a
wind shear alert after they start the takeoff roll and may elect to abort the takeoff. Aircraft on approach receiving
an alert may elect to go around or perform a wind shear escape maneuver.
PREFERRED IFR ROUTES- Routes established between busier airports to increase system efficiency and
capacity. They normally extend through one or more ARTCC areas and are designed to achieve balanced traffic
flows among high density terminals. IFR clearances are issued on the basis of these routes except when severe
weather avoidance procedures or other factors dictate otherwise. Preferred IFR Routes are listed in the Chart
Supplement U.S., and are also available at https://www.fly.faa.gov/rmt/nfdc_preferred_routes_database.jsp. If
a flight is planned to or from an area having such routes but the departure or arrival point is not listed in the Chart
Supplement U.S., pilots may use that part of a Preferred IFR Route which is appropriate for the departure or
arrival point that is listed. Preferred IFR Routes may be defined by DPs, SIDs, or STARs; NAVAIDs, Waypoints,
etc.; high or low altitude airways; or any combinations thereof. Because they often share elements with adapted
routes, pilots" use of preferred IFR routes can minimize flight plan route amendments.
(See ADAPTED ROUTES.)
(See CENTER"S AREA.)
(See INSTRUMENT APPROACH PROCEDURE.)
(See INSTRUMENT DEPARTURE PROCEDURE.)
(See STANDARD TERMINAL ARRIVAL.)
(Refer to CHART SUPPLEMENT U.S.)

PRE-FLIGHT PILOT BRIEFING-
(See PILOT BRIEFING.)

PREVAILING VISIBILITY-
(See VISIBILITY.)