Pilot/Controller Glossary  8/15/19  P  (See PREARRANGED COORDINATION  PROCEDURES.)  (See PROPOSED DEPARTURE TIME.)  PAN-PAN- The international radio-telephony urgen- cy signal. When repeated three times, indicates  uncertainty or alert followed by the nature of the  urgency.  (See MAYDAY.)  (Refer to AIM.)  (See PRECISION APPROACH RADAR.)  (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 Navi- gation (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).  (See PROPOSED BOUNDARY CROSSING  TIME.)  (See ICAO Term PERFORMANCE-BASED  NAVIGATION.)  (See  PRE-DEPARTURE CLEARANCE .)  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.  PHOTO RECONNAISSANCE- Military activity  that requires locating individual photo targets and  navigating to the targets at a preplanned angle and  altitude. The activity normally requires a lateral route  width of 16 NM and altitude range of 1,500 feet to  10,000 feet AGL.  PILOT BRIEFING- A service provided by the FSS  to assist pilots in flight planning. Briefing items may  include weather information, NOTAMS, military  activities, flow control information, and other items  as requested.  (Refer to AIM.)  PILOT IN COMMAND- The pilot responsible for  the operation and safety of an aircraft during flight  time.  (Refer to 14 CFR Part 91.)  PILOT WEATHER REPORT- A report of meteoro- logical phenomena encountered by aircraft in flight.  (Refer to AIM.)  PILOT'S DISCRETION- When used in conjunc- tion with altitude assignments, means that ATC has  offered the pilot the option of starting climb or  descent whenever he/she wishes and conducting the  climb or descent at any rate he/she wishes. He/she  may temporarily level off at any intermediate  altitude. However, once he/she has vacated an  altitude, he/she may not return to that altitude.  PBCT- PBN- PDC- PAR- PAR [ICAO]- P TIME- P-ACP- PCG P-1 