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{{Article Infobox2
{{Article Infobox2
|Category=Applications
|Category=Applications
|Title={{PAGENAME}}
|Editors=GMV
|Authors=GMV.
|Level=Intermediate
|Level=Medium
|YearOfPublication=2011
|YearOfPublication=2011
|Logo=GMV
|Logo=GMV
}}
}}
In aeronautical applications, satellite navigation has long been an additional means for localization purposes. The development of GNSS has provided a supplementary positioning service for many flight phases, in leisure flying as well as commercial air transport. Refining and improving satellite navigation through augmentation systems will assist pilots in all flight phases, from taxing, to take-off, en-route flying, and landing in all weather conditions, reaching the level of safety that will be required to cope with the continuous increase in the number of flights<ref name="esa-ec">[https://ec.europa.eu/commission/index_en Galileo Application Sheet - Aviation Applications], ESA and European Commission, October 2002</ref>.


In aeronautical applications, satellite navigation has long been an additional means for localisation purposes. The development of GNSS has provided a supplementary positioning service for many flight phases, in leisure flying as well as commercial air transport. Refining and improving satellite navigation through augmentation systems will assist pilots in all flight phases, from movement on the ground, to take-off, en-route flying, and landing in all weather conditions, reaching the level of safety that will be required to cope with the continuous increase in the number of flights.<ref name="esa-ec">[http://www.galileoic.org/la/files/Aviation.pdf Galileo Application Sheet - Aviation Applications], ESA and European Commission, October 2002</ref>
When planning aircraft routes and landing schedules at busy airports, it is essential to ensure that airplanes are always a safe distance from each other. GNSS, will provide a guaranteed service with sufficient accuracy to allow airlines and pilots to know their position reliably and precisely enough to make substantial efficiency savings.<ref name="gsa" >[http://www.esa.int/esaMI/Navigation_Applications/SEMZSFEVL2F_0.html ESA Portal - Navigation Applications - Aviation], ESA, June 2007</ref>  
 
When planning aircraft routes and landing schedules at busy airports, it is essential to ensure that aircraft are always a safe distance from each other. GNSS, will provide a guaranteed service with sufficient accuracy to allow airlines and pilots to know their position reliably and precisely enough to make substantial efficiency savings.<ref name="gsa" >[http://www.esa.int/esaMI/Navigation_Applications/SEMZSFEVL2F_0.html ESA Portal - Navigation Applications - Aviation], ESA, June 2007</ref>  
   
   
   
   
== Overview of Aviation Applications ==
== Overview of Aviation Applications ==


GNSS overcomes many of the inadequacies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning. This is especially relevant for General Aviation which often use smaller airports, where the adequate systems represent a large investment.
GNSS overcomes many of the inadequacies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning service. This is especially relevant for General Aviation which often uses smaller airports, where the adequate systems represent a large investment.


Total GNSS aviation segment revenues will reach €415 mln in 2020 driven by the increase in general aviation aircraft device sales, that will account for about 98% of the total. GNSS penetration in aviation market will reach 58% by 2015 and 75% by 2020, determined by the SESAR regulation in Europe, that will account for a 100% GNSS penetration by 2020.<ref name="Market_Report">[http://www.gsa.europa.eu/files/dmfile/GSAGNSSMarketreportIssue1.pdf GSA GNSS Market Report – Issue 3], October 2010.</ref>
According to the [[GNSS Market Report#Aviation|GNSS Market Report, Issue 3]], total GNSS aviation segment revenues are expected to reach €900 mln in 2022 driven by revenue increasing of the Visual Flight Rules (VFR) sub-segment, with leisure flyers using GNSS as a supplementary information source. The use of GNSS within all aviation segments is expected to increase over the next decade reaching a penetration of over 90% in 2022.


The original basic GNSS equipment is evolving due to the development of augmentations such as SBAS, GBAS and ABAS, while the introduction of Galileo and the modernization of GPS and GLONASS will further improve GNSS performance. The use of system which integrates GNSS and inertial systems is also expanding.<ref name="PNB-manual" >[http://www.icao.int/icao/en/anb/meetings/perf2007/_PBN%20Manual_W-Draft%205.1_FINAL%2007MAR2007.pdf Performance-based navigation Manual], ICAO 2008</ref>  
The original basic GNSS equipment is evolving due to the development of augmentation systems such as SBAS, GBAS and ABAS, while the introduction of Galileo and the modernization of GPS and GLONASS will further improve GNSS performance. The use of systems that integrate GNSS and inertial systems is also expanding.<ref name="PNB-manual" >[https://www.icao.int/Pages/default.aspx Performance-based navigation Manual], ICAO, March 2007</ref>  


The following section provides an overview of augmentation systems used in aviation applications.
The following section provides an overview of augmentation systems used in aviation applications.


In this section we also detail four of the most common and promising aviation applications for the GNSS technology.
== GNSS Augmentation ==  
 
 
=== GNSS Augmentation ===  


There are 3 main types of augmentation to allow the use of GNSS applications in aviation, ABAS (Aircraft Based Augmentation Systems), [[GBAS|GBAS]] (Ground Based Augmentation System) and [[SBAS|SBAS]] (Satellite Based Augmentation System).
Aviation GNSS applications and products have been one of the main drivers of [[GNSS Augmentation]] systems. The ICAO GNSS Standards <ref>SARPS Amendment 77, Annex 10 to the Convention on International Civil Aviation, Aeronautical Telecommunications: International Standards and Recommended Practices, Volume 1, Radio Navigation Aids, November 2002.</ref> defines three architectures to augment GNSS constellations for aviation, ABAS (Aircraft Based Augmentation Systems), [[Ground-Based Augmentation System (GBAS)|GBAS]] (Ground Based Augmentation System) and [[SBAS Fundamentals|SBAS]] (Satellite Based Augmentation System).


Present ground-based navigation aids are monitored, and the monitor takes action if erroneous signals are being radiated. On the present configuration of the GNSS system it may take considerable time before users become aware of any malfunctioning.  
Present ground-based navigation aids are monitored, and the monitor takes action if erroneous signals are being radiated. On the present configuration of the GNSS system it may take considerable time before users become aware of any malfunctioning.  


Aircraft-based augmentation can provide this information as necessary for supplemental means of navigation. An augmentation system that augments and/or integrates the information obtained from the other GNSS elements with information available on board the aircraft.


 
=== ABAS ===
==== ABAS ====
The Aircraft based augmentation can provide GNSS information as necessary for supplemental means of navigation. An ABAS is basically a system that augments and/or integrates the information obtained from the other GNSS elements with information available on board the aircraft.
The Aircraft based augmentation can provide GNSS information as necessary for supplemental means of navigation. An ABAS is basically a system that augments and/or integrates the information obtained from the other GNSS elements with information available on board the aircraft.


The Aircraft based augmentation system can be implemented by:  
The Aircraft based augmentation system can be implemented by:<ref name="PNB-manual" />


:* '''Receiver Autonomous Integrity Monitoring (RAIM)''' whereby a GNSS receiver processor determines the integrity of GNSS position using GPS signals augmented with altitude (baroaiding). The RAIM limit for en route operations is 2.0 NM and for terminal operations is 1.0 NM.
:* '''Receiver Autonomous Integrity Monitoring (RAIM)''' whereby a GNSS receiver processor determines the integrity of GNSS position using GPS signals or GPS signals augmented with altitude (baroaiding).


:* '''Aircraft Autonomous Integrity Monitoring (AAIM)''' whereby the GNSS signal is integrated with other sensors, such as the Inertial navigation system (INS) which can detect and reject spurious information from the GNSS.
:* '''Aircraft Autonomous Integrity Monitoring (AAIM)''' whereby the GNSS signal is integrated with other navigation sensors, such as the inertial navigation system (INS) which can perform an integrity check on GNSS data when RAIM is unavailable.


Nowadays, around 70% of European flights are made by aircraft equipped with GPS and RAIM.
Nowadays, around 70% of European flights are made by aircraft equipped with GPS and RAIM.<ref>[http://www.enri.go.jp/eiwac/2009/ppts/EUROCONTROLPolicyOnGNSSinEurope.pdf EUROCONTROL]Policy on GNSS in Europe, 2009</ref>


 
=== GBAS ===
 
==== GBAS ====


The GBAS provide GNSS integrity monitoring through data obtained from the ground. They also increase the accuracy of satellite navigation, clearing the way for GNSS precision approach and landing.
The GBAS provide GNSS integrity monitoring through data obtained from the ground. They also increase the accuracy of satellite navigation, clearing the way for GNSS precision approach and landing.
A ground station at the airport transmits locally-relevant corrections, integrity data and approach data to aircraft at the terminal area in the VHF band.
A ground station at the airport transmits locally-relevant corrections, integrity data and approach data to aircraft at the terminal area in the VHF band.
GBAS, will increasingly support [[wikipedia:Instrument landing system#ILS categories|CAT II/III]] operations where economically beneficial once enhanced GNSS become available. It is assumed that all GBAS for CAT I stations will be upgraded to CATII/III stations.<ref name="faa">[http://www.faa.gov/ Federal Aviation Administration Site], Global Positioning System</ref>
GBAS, will increasingly support [[SKYbrary:Precision_Approach|CAT II/III]] operations where economically beneficial once enhanced GNSS become available. It is assumed that all GBAS stations for CAT I operations will be upgraded to CATII/III operations.<ref name="faa">[http://www.faa.gov/ Federal Aviation Administration Site], Global Positioning System</ref>
 
Detailed information about GBAS can be found [[GBAS|here]].


Detailed information about GBAS can be found [[Ground-Based Augmentation System (GBAS)|here]].


==== SBAS ====
=== SBAS ===


* '''WAAS'''
SBAS systems implemented in in several regions improves the accuracy, reliability and integrity of the GPS signal. GNSS-SBAS navigators that meet international organizations regulations (such as ICAO, FAA, Eurocontrol) may be used for sole means of navigation for all phases of flight, including precision approach at airports. <ref name="Garmin" >[https://www.garmin.com/en-US/ Garmin WAAS Certification]</ref>
:The WAAS system implemented in USA improves the accuracy, reliability and integrity of the GPS signal. GPS-WAAS navigators that meet Federal Aviation Administration (FAA) WAAS regulations may be used for sole means of navigation for all phases of flight, including precision approach at airports. <ref name="Garmin" >[http://www8.garmin.com/pressroom/aviation/110906.html Garmin WAAS Certification]</ref>


:The Wide Area Augmentation System offers an opportunity for airports to gain [[wikipedia:Instrument landing system|Instrument Landing System (ILS)]] approach capability without the purchase or installation of any ground-based navigation equipment at the airport.
The SBAS systems offer an opportunity for airports to gain [[SKYbrary:ILS|Instrument Landing System (ILS)]] approach capability without the purchase or installation of any ground-based navigation equipment at the airport.
   
   
:The WAAS vertically guided approach procedures are considered LPV (Localizer Performance with Vertical guidance) and provide ILS (Instrument Landing System) equivalent approach minimums as low as 200 feet at qualifying airports. Actual minimums are based on an airport’s current infrastructure, as well as an evaluation of any existing obstructions.<ref name="faa" />
The SBAS vertically guided approach procedures are considered LPV (Localizer Performance with Vertical guidance) and provide ILS (Instrument Landing System) equivalent approach minimums as low as 200 feet at qualifying airports. Actual minimums are based on an airport’s current infrastructure, as well as an evaluation of any existing obstructions.<ref name="faa" />
 
:Detailed information about WAAS can be found [[WAAS|here]].
 
* '''EGNOS'''
:EGNOS is the satellite-based augmentation system that improves the accuracy of satellite navigation signals over Europe. The signals are guaranteed to the extremely high reliability set out by the International Civil Aviation Organisation standard.
 
:EGNOS offers the aviation industry the means to provide accurate and safe vertically guided approaches to smaller airports and its introduction will reduce delays, diversions and cancellations of flights into and out of these airfields while improving passenger safety.


:The EGNOS Safety-of-Life signal was recently formally declared available to aviation. For the first time, space-based navigation signals augmented by this system have become officially usable for the critical task of vertically guiding aircraft during landing approaches. <ref>[http://www.esa.int/esaCP/SEM98MUTLKG_index_0.html ESA Portal], EGNOS navigation system begins serving Europe’s aircraft</ref>
In Europe the EGNOS Safety-of-Life signal was formally declared available to aviation in March 2011. For the first time, space-based navigation signals augmented by this system have become officially usable for the critical task of vertically guiding aircraft during landing approaches. <ref>[http://www.esa.int/esaCP/SEM98MUTLKG_index_0.html ESA Portal], EGNOS navigation system begins serving Europe’s aircraft</ref>
 
:Detailed information about EGNOS can be found [[EGNOS|here]].


Detailed information about SBAS can be found [[SBAS Fundamentals|here]].


== En Route Navigation ==
== En Route Navigation ==


[[File:Garmin_G1000_Diamond_DA-42.jpg|right|thumb|150px|En Route Navigation]]
[[File:Multi_Function_Display_Garmin_G1000.jpg|right|thumb|150px|En Route Navigation]]


GNSS overcomes many of the deficiencies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning.<ref name="gsa" />
GNSS overcomes many of the deficiencies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning.<ref name="gsa" />
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Approach, landing and take-off are critical flight phases and the major need of commercial operators is to have full operations in all weather conditions. As a consequence, precision approach is a mandatory requirement.
Approach, landing and take-off are critical flight phases and the major need of commercial operators is to have full operations in all weather conditions. As a consequence, precision approach is a mandatory requirement.


The GNSS, with the aid of ground-based augmentation (local elements), will satisfy the needs for precision approach as defined in the aeronautical standards, and could replace or complement the navigation infrastructure of airports in regions where the system is inadequate. The most prominent example is the airports that not equipped with instrument landing systems.  
The GNSS, with the aid of ground-based augmentation (local elements), will satisfy the needs for precision approach as defined in the aeronautical standards, and could replace or complement the navigation infrastructure of airports in regions where the system is inadequate. The most prominent example is the airports that are not equipped with instrument landing systems.  


Detailed information about Approach can be found [[Approach|here]].
Detailed information about Approach can be found [[Approach|here]].


== Attitude Determination ==
== Attitude Determination ==
Line 105: Line 85:
[[File:Flight dynamics with text.png|right|thumb|150px|Flight dynamics]]
[[File:Flight dynamics with text.png|right|thumb|150px|Flight dynamics]]


The Attitude Determination is one of the many applications where GNSS can be effectively employed.<ref name="tudelft" >[http://www.lr.tudelft.nl/live/pagina.jsp?id=11407d44-13a8-4c17-8e2e-8b089a8bdfa0&lang=en TUDelft] - Attitude Determination and Formation Flying</ref>
The Attitude Determination is one of the many applications where GNSS can be effectively employed.<ref name="tudelft" >[https://www.tudelft.nl/ TUDelft] - Attitude Determination and Formation Flying</ref>


The attitude of an aircraft, i.e., the orientation in space, can be determined by measuring the relative positions of multiple GNSS antennas mounted on different positions of the aircraft.  
The attitude of an aircraft, i.e., the orientation in space, can be determined by measuring the relative positions of multiple GNSS antennas mounted on different positions of the aircraft.  
Line 111: Line 91:
<ref name="nlr">[http://www.nlr.nl/smartsite.dws?id=2614 Static and dynamic GNSS attitude function testing of airborne equipment], H. Kannemans, National Aerospace Laboratory NLR, April 2005</ref>
<ref name="nlr">[http://www.nlr.nl/smartsite.dws?id=2614 Static and dynamic GNSS attitude function testing of airborne equipment], H. Kannemans, National Aerospace Laboratory NLR, April 2005</ref>


Detailed information about Altitude Determination can be found [[Attitude Determination|here]].
Detailed information about Attitude Determination can be found [[Attitude Determination|here]].
 


== Air Traffic Control ==
== Air Traffic Control ==


Air traffic controllers need position, heading, speed and time information for the continuous management of all aircraft. Some areas of the world, lack the appropriate ground infrastructure, including secondary radar and communication links. Standardized transmission of GNSS navigation data will lead to advanced systems and techniques for safer air traffic monitoring.
Air traffic controllers need position, heading, speed and time information for the continuous management of all aircraft. Some areas of the world lack the appropriate ground infrastructure, including secondary radar and communication links. Standardized transmission of GNSS navigation data will lead to advanced systems and techniques for safer air traffic monitoring.


The [[wikipedia:Automatic dependent surveillance-broadcast|Automatic dependent surveillance-broadcast (ADS-B)]] is currently the most important  system used in ATC side, which relies on GNSS as primary data source, to obtain aircraft's horizontal positions.
The [[SKYbrary:ADS-B|Automatic dependent surveillance-broadcast (ADS-B)]] is currently the most important  system used in ATC side, which relies on GNSS as primary data source, to obtain aircraft's horizontal positions.
   
   
Detailed information about Air Traffic Control can be found [[Air Traffic Control|here]].
Detailed information about Air Traffic Control can be found [[Air Traffic Control|here]].


== Notes ==
== Notes ==

Latest revision as of 11:36, 21 May 2021


ApplicationsApplications
Title Aviation Applications
Edited by GMV
Level Intermediate
Year of Publication 2011
Logo GMV.png

In aeronautical applications, satellite navigation has long been an additional means for localization purposes. The development of GNSS has provided a supplementary positioning service for many flight phases, in leisure flying as well as commercial air transport. Refining and improving satellite navigation through augmentation systems will assist pilots in all flight phases, from taxing, to take-off, en-route flying, and landing in all weather conditions, reaching the level of safety that will be required to cope with the continuous increase in the number of flights[1].

When planning aircraft routes and landing schedules at busy airports, it is essential to ensure that airplanes are always a safe distance from each other. GNSS, will provide a guaranteed service with sufficient accuracy to allow airlines and pilots to know their position reliably and precisely enough to make substantial efficiency savings.[2]


Overview of Aviation Applications

GNSS overcomes many of the inadequacies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning service. This is especially relevant for General Aviation which often uses smaller airports, where the adequate systems represent a large investment.

According to the GNSS Market Report, Issue 3, total GNSS aviation segment revenues are expected to reach €900 mln in 2022 driven by revenue increasing of the Visual Flight Rules (VFR) sub-segment, with leisure flyers using GNSS as a supplementary information source. The use of GNSS within all aviation segments is expected to increase over the next decade reaching a penetration of over 90% in 2022.

The original basic GNSS equipment is evolving due to the development of augmentation systems such as SBAS, GBAS and ABAS, while the introduction of Galileo and the modernization of GPS and GLONASS will further improve GNSS performance. The use of systems that integrate GNSS and inertial systems is also expanding.[3]

The following section provides an overview of augmentation systems used in aviation applications.

GNSS Augmentation

Aviation GNSS applications and products have been one of the main drivers of GNSS Augmentation systems. The ICAO GNSS Standards [4] defines three architectures to augment GNSS constellations for aviation, ABAS (Aircraft Based Augmentation Systems), GBAS (Ground Based Augmentation System) and SBAS (Satellite Based Augmentation System).

Present ground-based navigation aids are monitored, and the monitor takes action if erroneous signals are being radiated. On the present configuration of the GNSS system it may take considerable time before users become aware of any malfunctioning.


ABAS

The Aircraft based augmentation can provide GNSS information as necessary for supplemental means of navigation. An ABAS is basically a system that augments and/or integrates the information obtained from the other GNSS elements with information available on board the aircraft.

The Aircraft based augmentation system can be implemented by:[3]

  • Receiver Autonomous Integrity Monitoring (RAIM) whereby a GNSS receiver processor determines the integrity of GNSS position using GPS signals or GPS signals augmented with altitude (baroaiding).
  • Aircraft Autonomous Integrity Monitoring (AAIM) whereby the GNSS signal is integrated with other navigation sensors, such as the inertial navigation system (INS) which can perform an integrity check on GNSS data when RAIM is unavailable.

Nowadays, around 70% of European flights are made by aircraft equipped with GPS and RAIM.[5]

GBAS

The GBAS provide GNSS integrity monitoring through data obtained from the ground. They also increase the accuracy of satellite navigation, clearing the way for GNSS precision approach and landing. A ground station at the airport transmits locally-relevant corrections, integrity data and approach data to aircraft at the terminal area in the VHF band. GBAS, will increasingly support CAT II/III operations where economically beneficial once enhanced GNSS become available. It is assumed that all GBAS stations for CAT I operations will be upgraded to CATII/III operations.[6]

Detailed information about GBAS can be found here.

SBAS

SBAS systems implemented in in several regions improves the accuracy, reliability and integrity of the GPS signal. GNSS-SBAS navigators that meet international organizations regulations (such as ICAO, FAA, Eurocontrol) may be used for sole means of navigation for all phases of flight, including precision approach at airports. [7]

The SBAS systems offer an opportunity for airports to gain Instrument Landing System (ILS) approach capability without the purchase or installation of any ground-based navigation equipment at the airport.

The SBAS vertically guided approach procedures are considered LPV (Localizer Performance with Vertical guidance) and provide ILS (Instrument Landing System) equivalent approach minimums as low as 200 feet at qualifying airports. Actual minimums are based on an airport’s current infrastructure, as well as an evaluation of any existing obstructions.[6]

In Europe the EGNOS Safety-of-Life signal was formally declared available to aviation in March 2011. For the first time, space-based navigation signals augmented by this system have become officially usable for the critical task of vertically guiding aircraft during landing approaches. [8]

Detailed information about SBAS can be found here.

En Route Navigation

En Route Navigation

GNSS overcomes many of the deficiencies in today’s air traffic infrastructure thanks to its accurate, continuous, all-weather positioning.[2] During en-route flight, the availability of GNSS will ensure high robustness through the redundancy and high reliability of the service.[1]

In the future, higher accuracy and service integrity will allow aircraft separation to be reduced in congested airspace, to cope with traffic growth. GNSS will be used in en-route flight phase of commercial aircraft.

Detailed information about En Route Navigation can be found here.


Approach

Portable GNSS device

Approach, landing and take-off are critical flight phases and the major need of commercial operators is to have full operations in all weather conditions. As a consequence, precision approach is a mandatory requirement.

The GNSS, with the aid of ground-based augmentation (local elements), will satisfy the needs for precision approach as defined in the aeronautical standards, and could replace or complement the navigation infrastructure of airports in regions where the system is inadequate. The most prominent example is the airports that are not equipped with instrument landing systems.

Detailed information about Approach can be found here.

Attitude Determination

Flight dynamics

The Attitude Determination is one of the many applications where GNSS can be effectively employed.[9]

The attitude of an aircraft, i.e., the orientation in space, can be determined by measuring the relative positions of multiple GNSS antennas mounted on different positions of the aircraft. Usually, a set of 3 or more GNSS antennas placed on board of an aircraft can provide the complete information to compute the aircrft's attitude. [10]

Detailed information about Attitude Determination can be found here.

Air Traffic Control

Air traffic controllers need position, heading, speed and time information for the continuous management of all aircraft. Some areas of the world lack the appropriate ground infrastructure, including secondary radar and communication links. Standardized transmission of GNSS navigation data will lead to advanced systems and techniques for safer air traffic monitoring.

The Automatic dependent surveillance-broadcast (ADS-B) is currently the most important system used in ATC side, which relies on GNSS as primary data source, to obtain aircraft's horizontal positions.

Detailed information about Air Traffic Control can be found here.

Notes


References

  1. ^ a b Galileo Application Sheet - Aviation Applications, ESA and European Commission, October 2002
  2. ^ a b ESA Portal - Navigation Applications - Aviation, ESA, June 2007
  3. ^ a b Performance-based navigation Manual, ICAO, March 2007
  4. ^ SARPS Amendment 77, Annex 10 to the Convention on International Civil Aviation, Aeronautical Telecommunications: International Standards and Recommended Practices, Volume 1, Radio Navigation Aids, November 2002.
  5. ^ EUROCONTROLPolicy on GNSS in Europe, 2009
  6. ^ a b Federal Aviation Administration Site, Global Positioning System
  7. ^ Garmin WAAS Certification
  8. ^ ESA Portal, EGNOS navigation system begins serving Europe’s aircraft
  9. ^ TUDelft - Attitude Determination and Formation Flying
  10. ^ Static and dynamic GNSS attitude function testing of airborne equipment, H. Kannemans, National Aerospace Laboratory NLR, April 2005