FullDescription:Navigation

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Aircraft Autonomous Integrity Monitoring

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receiver autonomous integrity monitoring (RAIM)

Global Navigation Satellite System (GNSS)

GLONASS

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Abbreviation

AAIM

Definition

A technology used to augment GPS and GLONASS within the GNSS 1 framework that uses information from the aircraft inertial navigation systems to cross-check the integrity of the GPS signal."

Definition Source

CANADA (2009) Transport Canada, Glossary for Pilots and Air Traffic Services Personnel, URL: [1]

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Aircraft-based augmentation system

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Receiver autonomous integrity monitoring (RAIM)

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Global Navigation Satellite System (GNSS)

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Abbreviation

ABAS

Definition

An augmentation system which augments and/or integrates the information obtained from the other GNSS elements with information available on board the aircraft.

Definition Source

ICAO, Official definition added to An 10/I by Amdt 76 (01/11/2001)

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Aneroid barometer

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pressure altimeter

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Abbreviation

Definition

An instrument for measuring atmospheric pressure.

Definition Source

American Meteorological Society, Glossary of Meteorology [2]

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Anti-spoofing

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A-S

A/S

Definition

[within the GPS system]... the ability to essentially "turn off" the P-code or invoke an encrypted code (Y-code) as a means of denying access to the P-code to all but authorized users. The rationale for doing this is to keep adversaries from sending out false signals with the GPS signature to create confusion and cause users to misposition themselves.

Definition Source

ICAO (1998) WGS84 Implementation Manual, Version 2.4, Appendix A "The Global Positioning System (GPS)"

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Area navigation

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Term area navigation
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performance-based navigation (PBN)

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Precision Area Navigation (P-RNAV)

Abbreviation

RNAV

Definition

A method of navigation which permits aircraft operations on any desired flight path within the coverage of ground- or spaced-based navigation aids or within the limits of the capability of self-contained aids, or a combination of these.

Definition Source

ICAO, Official term and definition added to AN 2 by Amdt 41 (20/07/2008), AN 3 by Amdt 75 (2010), AN 4 by Amdt 55 (2009), AN 6/I by Amdt 32 (20/07/2008), AN 6/III by Amdt 13 (20/07/2008), AN 10/I by Amdt 83 (20/07/2008), AN 15 by Amdt 35 (2009) and modified by Amdt 46 to AN 11 (20/07/2008)

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Area navigation includes performance-based navigation as well as other operations that do not meet the definition of performance-based navigation. (Note source: ICAO)

Area navigation (RNAV) specification

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Term area navigation (RNAV) specification
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required navigation performance (RNP) specification

area navigation

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navigation specification

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Abbreviation

Definition

A navigation specification based on area navigation that does not include the requirement for performance monitoring and alerting, designated by the prefix RNAV, e.g. RNAV 5, RNAV 1.

Definition Source

ICAO (2006) Official definition, Annex 10, Vol. I, Aeronautical Communications - Radio Navigation Aids

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Area navigation route

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Term area navigation route
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required navigation performance

ATS route

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area navigation

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Abbreviation

Definition

An ATS route established for the use of aircraft capable of employing area navigation.

Definition Source

ICAO, Official definition, DOC 9613 Manual on Required Navigation Performance (RNP) 2008, 3rd ed., p. I-(xix)

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Autoland approach

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Abbreviation

Definition

a precision instrument approach to touchdown and, in some cases, through the landing rollout. An autoland approach is performed by the aircraft autopilot which is receiving position information and/or steering commands from onboard navigation equipment.

Definition Source

FAA, Pilot Controller Glossary (2010), URL:[3]

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Barometric altitude

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Term barometric altitude
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pressure altimeter

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Definition

Geopotential altitude in the Earth's atmosphere above mean standard sea level pressure datum plane, measured by a pressure (barometric) altimeter.

Definition Source

ICAO, doc. GNSSP/2 Rep. p. 1A-43

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Basic area navigation

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performance-based navigation (PBN)

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area navigation (RNAV)

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Abbreviation

B-RNAV

Definition

European RNAV operations which satisfy a required track, maintaining accuracy of ± 5 NM for at least 95% of the flight time. This level of navigation accuracy is comparable with that which can be achieved by conventional navigation techniques on ATC routes (defined by VOR/DME, when VORs are less than 100 NM apart).

Definition Source

EUROCONTROL, Skyway magazine No.46 - Autumn/Winter 2007

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Beacon

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Term beacon
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radio beacon

radar beacon

Abbreviation

Definition

"(a) A light, group of lights, electronic apparatus, or other device that guides, orients, or warns aircraft, spacecraft, etc., in flight.

(b) A structure, building, or station where such a device is mounted or located."

Definition Source

NATO: NORTH ATLANTIC TREATY ORGANIZATION, Advisory Group for Aerospace Research and Development (AGARD/NATO) (1980), "Agard Multilingual Aeronautical Dictionary", Second Edition, London

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Coverage

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Definition

1. (radio-navigation) The coverage provided by a radio-navigation system is that surface area or space volume in which the signals are adequate to permit the user to determine position to a specified level of accuracy.

Coverage is influenced by system geometry, signal power levels, receiver sensitivity, atmospheric noise conditions and other factors which affect signal availability.

2. (general) "feature that acts as a function to return values from its range for any direct position within its spatial, temporal, or spatiotemporal domain.

EXAMPLE: Examples include a raster image, polygon overlay or digital elevation matrix.

NOTE: In other words, a coverage is a feature that has multiple values for each attribute type, where each direct position within the geometric representation of the feature has a single value for each attribute type."

Definition Source

1. ICAO Document 9613, Manual on Required Navigation Performance (RNP), Appendix A

2. ISO Standard 19123 (Geographic Information - Schema for coverage geometry and functions) (2005)

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GLONASS

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Term GLONASS
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aircraft-based augmentation system (ABAS)

ground-based augmentation system (GBAS)

Satellite Based Augmentation System (SBAS)

Broader term

Global Navigation Satellite System (GNSS)

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Abbreviation

Definition

The satellite navigation system operated by the Russian Federation.

Definition Source

ICAO, Official definition added to An 10/I by Amdt 76, 2001

Note

Full form of GLONASS: Global Navigation Satellite System

Ground-based augmentation system

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Term ground-based augmentation system
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Satellite Based Augmentation System (SBAS)

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Global Navigation Satellite System (GNSS)

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Local Area Augmentation System (LAAS)

Abbreviation

GBAS

Definition

An augmentation system in which the user receives augmentation information directly from a ground-based transmitter.

Definition Source

ICAO, Official definition, PANS-OPS/II Procedures for Air Navigation Services — Aircraft Operations — Construction of Visual and Instrument Flight Procedures [Doc 8168/II] 2006

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Local Area Augmentation System

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Wide Area Augmentation System (WAAS)

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ground-based augmentation system(GBAS)

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Abbreviation

LAAS

Definition

an augmentation to GPS that focuses its service on the airport area (approximately a 20-30 mile radius).

Definition Source

FAA (2009) homepage, Navigation Services, URL: http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/hill/index.cfm#waas

Note

Systems such as LAAS are known as ground-based augmentation systems (GBAS). LAAS broadcasts its correction message via a very high frequency (VHF) radio data link from a ground-based transmitter. LAAS will yield the extremely high accuracy, availability, and integrity necessary for Category I, II, and III precision approaches, and will provide the ability for more flexible, curved approach paths. LAAS demonstrated accuracy is less than 1 meter in both the horizontal and vertical axis.

Minimum Vectoring Altitude

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vectoring

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Abbreviation

MVA

Definition

the lowest altitude, expressed in feet AMSL (Above Mean Sea Level), to which a radar controller may issue aircraft altitude clearances during vectoring/direct routing except if otherwise authorized for radar approaches, departures and missed approaches.

Definition Source

SKYBRARY, reference tool for aviation safety knowledge, [4]

Note

In some sources, this altitude is also referred to as Minimum Flight Altitude (MFA), Minimum Radar Vectoring Altitude (MRVA) or ATC Surveillance Minimum Altitude (ASMA). (same source)

Mixed navigation environment

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area navigation (RNAV)

required navigation performance (RNP)

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Definition

An environment where different navigation specifications may be applied within the same airspace (e.g. RNP 10 routes and RNP 4 routes in the same airspace) or where operations using conventional navigation are allowed in the same airspace with RNAV or RNP applications.

Definition Source

ICAO (2010), doc. 9931 (CDO Manual)

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Monitored approach

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shared approach

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Definition

a specific procedure for pilot task sharing. It involves one pilot flying (or managing) the aircraft on approach exclusively ‘head down’ by reference to the flight instruments whilst the other monitors.

Definition Source

SKYBRARY, reference database for aviation safety knowledge[5]

Note

Not later than the approach of the applicable DA/DH or MDA/MDH, the monitoring pilot seeks visual external references so that when the ‘head-down’ pilot calls “Decide”, they are in a position to make a prompt and unequivocal call of either call “Land” or "Go-Around". If the call is “Go Around”, the head-down pilot flies the prescribed or ad hoc cleared Missed Approach and the monitoring pilot continues in that role. If the call is “Land”, the pilot who has been monitoring and has made that call takes over as PF and continues to the landing. If visual reference should be lost below DA/MDA then the pilot who has taken over as PF must commence the go around before handing over to the other pilot at a suitable point during the climb-out.


The monitored approach has sometimes been described as a “delegated” approach compared to the description of the traditional approach, where the both a landing and a go around are flown by the pilot who made the approach, which has been called an “assisted” approach. (same source)

Nautical mile

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Abbreviation

NM

Definition

The length equal to 1 852 metres exactly.

Definition Source

ICAO (2010) Official definition, ANNEX 5 Units of Measurement to be Used in Air and Ground Operations

Note

1 nautical mile (6 080 feet) = 1.8531 kilometres

Navigation specification

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Term navigation specification
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area navigation (RNAV) specification

required navigation performance (RNP) specification

Abbreviation

Definition

A set of aircraft and flight crew requirements needed to support performance-based navigation operations within a defined airspace. There are two kinds of navigation specifications:

Required navigation performance (RNP) specification. A navigation specification based on area navigation that includes the requirement for performance monitoring and alerting, designated by the prefix RNP, e.g. RNP 4, RNP APCH.

Area navigation (RNAV) specification. A navigation specification based on area navigation that does not include the requirement for performance monitoring and alerting, designated by the prefix RNAV, e.g. RNAV 5, RNAV 1.

Definition Source

ICAO (2006) Official definition, Annex 10, Vol. I, Aeronautical Telecommunications — Radio Navigation Aids

Note

The term RNP, previously defined as “a statement of the navigation performance necessary for operation within a defined airspace”, has been removed (...) as the concept of RNP has been overtaken by the concept of PBN. The term RNP (...) is now solely used in the context of navigation specifications that require performance monitoring and alerting, e.g. RNP 4 refers to the aircraft and operating requirements, including a 4 NM lateral performance with on-board performance monitoring and alerting that are detailed in The PNB Manual. (same source)

Non-precision approach

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precision approach

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Abbreviation

NPA

Definition

an instrument approach and landing which utilises lateral guidance but does not utilise vertical guidance. (ICAO Annex 6) For pilots of older aircraft, in which use of automated systems to assist in flying the approach is limited, a high degree of piloting skill is required to fly such approaches accurately and the frequent practice which many pilots need to achieve this can be difficult to come by if precision approaches are the normal method used

Definition Source

EASA (2013) European Aviation Safety Plan 2013-2016

Note

"Approaches made using barometric altitude, termed non-precision approaches, require a minimum descent altitude above the local terrain that ensures that there is no risk of collision with the terrain." source: ICAO (2006)PANS-OPS/II [Doc 8168/II]

Performance-based navigation

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Term performance-based navigation
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SESAR

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area navigation (RNAV)

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PBN

Definition

Area navigation based on performance requirements for aircraft operating along an ATS route, on an instrument approach procedure or in a designated airspace.

Definition Source

ICAO, Official term and definition added to AN 3 by Amdt 75 (2010), AN 4 by Amdt 55 (2009), AN 6/I by Amdt 32 (20/07/2008), An 6/II by Amdt 27 (20/07/2008), AN 6/III by Amdt 13 (20/07/2008), AN 10/I by Amdt 83 (20/07/2008), AN 11 by Amdt 46 (20/07/2008) and to AN 15 by Amdt 35 (2009)

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. (Note source:ICAO)

Lexicon Release

Lexicon Release 2015.2

Point Merge

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Flight Management System (FMS)

Continuous descent operation (CDO)

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Precision Area Navigation (P-RNAV)

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Abbreviation

Definition

a specific P-RNAV procedure with built-in continuous descent ready for deployment in TMA.

Definition Source

EUROCONTROL (2010) EUROCONTROL EXPERIMENTAL CENTRE, POINT MERGE IN EXTENDED TERMINAL AREA (PMS-TE 2009-2010), EEC Technical/Scientific Report No. 2010-011

Note

Point Merge is a systemised method for merging arrival flows with existing technology developed by the EUROCONTROL Experimental Centre. It is designed to enable extensive use of lateral guidance by the FMS and continuous descent, even under high traffic load. Point Merge is based on a specific P-RNAV route structure (denoted Point Merge System) that is made of a point (the merge point) and pre-defined legs (the sequencing legs) equidistant from this point (and vertically separated).

(same source)

Precision Area Navigation

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basic area navigation (B-RNAV)

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area navigation (RNAV)

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Abbreviation

P-RNAV

Definition

A European RNAV navigation specification with a required track-keeping accuracy of ±1 NM for at least 95% of the flight time, together with advanced functionality and a high integrity navigation database. P-RNAV capability can be achieved using inputs from DME/DME or GNSS and/or INS.

Definition Source

CAA, REGULATION GROUP FLIGHT OPERATIONS DIVISION COMMUNICATION 04/2008, Appendix B

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Lexicon Release

Lexicon Release 2016.1


Precision approach

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non-precision approach

precision approach (PA) procedure

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Abbreviation

PA

Definition

An approach in which range, azimuth, and glide slope information are provided to the pilot.

Definition Source

US Department of Defense (2005) Dictionary of Military and Associated Terms

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Precision approach (PA) procedure

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non-precision approach

precision approach

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Abbreviation

PA

Definition

1. An instrument approach procedure using precision lateral and vertical guidance with minima as determined by the category of operation.

Note.— Lateral and vertical guidance refers to the guidance provided either by:

a) a ground-based navigation aid; or

b) computer generated navigation data.

Definition Source

ICAO (2006), Official definition, PANS-OPS/I, Procedures for Air Navigation Services — Aircraft Operations — Flight Procedures [Doc 8168/I]

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Pressure altimeter

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barometric altimeter

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aneroid barometer

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Definition

An aneroid barometer calibrated to convert atmospheric pressure into altitude.

Definition Source

American Meteorological Society, Glossary of Meteorology [6]

Note

Altimeters use standard atmosphere pressure–height relations in converting pressure into altitude. Therefore, the altimeter shows indicated altitude, which may, and frequently does, differ from the actual altitude. An altimeter may be set to measure altitude from an arbitrarily chosen level. It is common practice to use mean sea level; the level of the constant-pressure surface of 29.92 in. of mercury is also used; and, less frequently, the constant-pressure surface of the pressure at airport height. See altimeter setting, pressure altitude. (same source)

RNP system

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required navigation performance (RNP)

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Definition

An area navigation system which supports on-board performance monitoring and alerting.

Definition Source

ICAO, DOC 9613 Manual on Required Navigation Performance (RNP) 2008, 3rd ed., p. I-(xx)

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Radar beacon

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Term radar beacon
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beacon

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Abbreviation

Definition

"A transponder beacon transmitting a coded signal on radar frequency, permitting an interrogating craft to determine the bearing and range of the transponder."

Definition Source

NATO: NORTH ATLANTIC TREATY ORGANIZATION, Advisory Group for Aerospace Research and Development (AGARD/NATO) (1980), "Agard Multilingual Aeronautical Dictionary", Second Edition, London

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Radio beacon

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beacon

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Abbreviation

Definition

"A radio transmitter whose radiations enable a craft to determine its own direction or position relative to the beacon by means of a communication receiver or direction finder."

Definition Source

NATO: NORTH ATLANTIC TREATY ORGANIZATION, Advisory Group for Aerospace Research and Development (AGARD/NATO) (1980), "Agard Multilingual Aeronautical Dictionary", Second Edition, London

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Receiver autonomous integrity monitoring

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Aircraft-based augmentation system (ABAS)

Global Navigation Satellite System (GNSS)

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Abbreviation

RAIM

Definition

1) A technique whereby a civil GNSS receiver / processor determines the integrity of the GNSS navigation signals without reference to senders or non-DoD integrity systems other than the receiver itself. This determination is achieved by consistency check among redundant pseudorange measurements.

2) A form of ABAS whereby a GNSS receiver processor determines the integrity of the GNSS navigation signals using only GPS signals or GPS signals augmented with altitude (baroaiding). This determination is achieved by a consistency check among redundant pseudo-range measurements.

Definition Source

1) EUROCONTROL EATMP Glossary, June 2001

2) ICAO, DOC 9613 Manual on Required Navigation Performance (RNP) 2008, 3rd ed., p. I-(xx)

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Required navigation performance

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SESAR

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Required Surveillance Performance (RSP)

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Abbreviation

RNP

Definition

A statement of the navigation performance necessary for operation within a defined airspace.

Definition Source

ICAO, Official definition, AN 6/I Operation of Aircraft — International Commercial Air Transport — Aeroplanes 2010

Note

Navigation performance and requirements are defined for a particular RNP type and/or application.

Lexicon Release

Lexicon Release 2015.2

Required navigation performance (RNP) specification

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area navigation (RNAV) specification

required navigation performance (RNP)

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navigation specification

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Abbreviation

Definition

A navigation specification based on area navigation that includes the requirement for performance monitoring and alerting, designated by the prefix RNP, e.g. RNP 4, RNP APCH.

Definition Source

ICAO (2006) Official definition, Annex 10, Vol. I, Aeronautical Communications - Radio navigation aids

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Satellite Based Augmentation System

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ground-based augmentation system (GBAS)

Broader term

Global Navigation Satellite System (GNSS)

Narrower term

Wide Area Augmentation System (WAAS)

Abbreviation

SBAS

Definition

A network of ground stations and satellites designed to receive navigation signals, improving the accuracy and ensuring the integrity of information for navigation and landing.

Definition Source

  • AIFDD

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Vectoring

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Minimum Vectoring Altitude

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Abbreviation

Definition

Provision of navigational guidance to aircraft in the form of specific headings, based on the use of an ATS surveillance system.

Definition Source

ICAO (2007) Official definition, doc. 4444: PANS-ATM, Procedures for Air Navigation Services — Air Traffic Management

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Vertical navigation

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Abbreviation

VNAV

Definition

A function of area navigation (RNAV) equipment which calculates, displays and provides guidance to a vertical profile or path.

Definition Source

FAA (2011) Pilot/Controller Glossary [7]

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Wide Area Augmentation System

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Local Area Augmentation System (LAAS)

Broader term

Satellite Based Augmentation System (SBAS)

Narrower term


Abbreviation

WAAS

Definition

a GPS-based navigation and landing system that provides precision guidance to aircraft at thousands of airports and airstrips where there is currently no precision landing capability.

Definition Source

FAA (2009) homepage, Navigation Services, URL: http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/hill/index.cfm#waas

Note

Systems such as WAAS are known as satellite-based augmentation systems (SBAS). WAAS is designed to improve the accuracy and ensure the integrity of information coming from GPS satellites.