4/20/23 

Pilot/Controller Glossary 

b. 

Advanced 

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 Required Navigation Performance (A

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RNP). A navigation specification based on RNP that 

requires advanced functions such as scalable RNP, radius

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to

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fix (RF) legs, and tactical parallel offsets. This 

sophisticated Navigation Specification (NavSpec) is designated by the abbreviation “A

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RNP”. 

c. 

Required Navigation Performance (RNP) Airspace. A generic term designating airspace, route(s), leg(s), 

operation(s), or procedure(s) where minimum required navigational performance (RNP) have been established. 

d. 

Actual Navigation Performance (ANP). A measure of the current estimated navigational performance. 

Also referred to as Estimated Position Error (EPE). 

e. 

Estimated Position Error (EPE). A measure of the current estimated navigational performance. Also 

referred to as Actual Navigation Performance (ANP). 

f. 

Lateral Navigation (LNAV). A function of area navigation (RNAV) equipment which calculates, displays, 

and provides lateral guidance to a profile or path. 

g. 

Vertical Navigation (VNAV). A function of area navigation (RNAV) equipment which calculates, displays, 

and provides vertical guidance to a profile or path. 

REROUTE IMPACT ASSESSMENT (RRIA)

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 A capability within the Traffic Flow Management System that 

is used to define and evaluate a potential reroute prior to implementation, with or without miles

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in

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trail (MIT) 

restrictions. RRIA functions estimate the impact on demand (e.g., sector loads) and performance (e.g., flight 

delay). Using RRIA, traffic management personnel can determine whether the reroute will sufficiently reduce 

demand in the Flow Constraint Area and not create excessive “spill over” demand in the adjacent airspace on 

a specific route segment or point of interest (POI). 

RESCUE COORDINATION CENTER (RCC)

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 A search and rescue (SAR) facility equipped and manned to 

coordinate and control SAR operations in an area designated by the SAR plan. The U.S. Coast Guard and the 

U.S. Air Force have responsibility for the operation of RCCs. 

(See ICAO term RESCUE CO-ORDINATION CENTRE.) 

RESCUE CO-ORDINATION CENTRE [ICAO]

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 A unit responsible for promoting efficient organization of 

search and rescue service and for coordinating the conduct of search and rescue operations within a search and 

rescue region. 

RESOLUTION ADVISORY

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 A display indication given to the pilot by the Traffic alert and Collision 

Avoidance System (TCAS II) recommending a maneuver to increase vertical separation relative to an intruding 

aircraft. Positive, negative, and vertical speed limit (VSL) advisories constitute the resolution advisories. A 

resolution advisory is also classified as corrective or preventive. 

RESTRICTED AREA

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(See SPECIAL USE AIRSPACE.) 
(See ICAO term RESTRICTED AREA.) 

RESTRICTED AREA [ICAO]

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 An airspace of defined dimensions, above the land areas or territorial waters 

of a State, within which the flight of aircraft is restricted in accordance with certain specified conditions. 

RESUME NORMAL SPEED

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 Used by ATC to advise a pilot to resume an aircraft’s normal operating speed. 

It is issued to terminate a speed adjustment where no published speed restrictions apply. It does not delete speed 

restrictions in published procedures of upcoming segments of flight. This does not relieve the pilot of those speed 

restrictions that are applicable to 14 CFR Section 91.117. 

RESUME OWN NAVIGATION

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Used by ATC to advise a pilot to resume his/her own navigational 

responsibility. It is issued after completion of a radar vector or when radar contact is lost while the aircraft is being 

radar vectored. 

(See RADAR CONTACT LOST.) 
(See RADAR SERVICE TERMINATED.

)

 

PCG R

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