Pilot/Controller Glossary

P TIME-
(See PROPOSED DEPARTURE TIME.)

P-ACP-
(See PREARRANGED COORDINATION PROCEDURES.)

PAN-PAN- The international radio-telephony urgency signal. When repeated three times, indicates uncertainty
or alert followed by the nature of the urgency.
(See MAYDAY.)
(Refer to AIM.)

PAO-
(See PUBLIC AIRCRAFT OPERATION.)
PAR-
(See PRECISION APPROACH RADAR.)

PAR [ICAO]-
(See ICAO Term PRECISION APPROACH RADAR.)

PARALLEL ILS APPROACHES- Approaches to parallel runways by IFR aircraft which, when established
inbound toward the airport on the adjacent final approach courses, are radar-separated by at least 2 miles.
(See FINAL APPROACH COURSE.)
(See SIMULTANEOUS ILS APPROACHES.)

PARALLEL OFFSET ROUTE- A parallel track to the left or right of the designated or established airway/route.
Normally associated with Area Navigation (RNAV) operations.
(See AREA NAVIGATION.)

PARALLEL RUNWAYS- Two or more runways at the same airport whose centerlines are parallel. In addition
to runway number, parallel runways are designated as L (left) and R (right) or, if three parallel runways exist,
L (left), C (center), and R (right).
PBCT-
(See PROPOSED BOUNDARY CROSSING TIME.)

PBN-
(See ICAO Term PERFORMANCE-BASED NAVIGATION.)

PDC-
(See PRE-DEPARTURE CLEARANCE.)

PDRR-
(See PRE-DEPARTURE REROUTE.)

PERFORMANCE-BASED NAVIGATION (PBN) [ICAO]- Area navigation based on performance
requirements for aircraft operating along an ATS route, on an instrument approach procedure or in a designated
airspace.
Note: Performance requirements are expressed in navigation specifications (RNAV specification, RNP
specification) in terms of accuracy, integrity, continuity, availability, and functionality needed for the proposed
operation in the context of a particular airspace concept.

PERMANENT ECHO- Radar signals reflected from fixed objects on the earth"s surface; e.g., buildings, towers,
terrain. Permanent echoes are distinguished from "ground clutter" by being definable locations rather than large
areas. Under certain conditions they may be used to check radar alignment.