GPS IN AVIATION GPS IN AVIATION AND THE COMING AND THE COMING

AGE OF AGE OF AUTOMATED AUTOMATED

LANDING SYSTEMSLANDING SYSTEMSBy Pete HandBy Pete Hand

FRS 144 April 17FRS 144 April 17thth, 2006, 2006

OutlineOutline

A Brief History of GPS used in A Brief History of GPS used in aviationaviation

Goals and Objectives Goals and Objectives GPS Aviation Technology throughout GPS Aviation Technology throughout

the yearsthe years ILSILS MLSMLS WAASWAAS LAASLAAS

Outline ContinuedOutline Continued

Automated LandingsAutomated Landings In the MilitaryIn the Military For Commercial useFor Commercial use The future of automated landing The future of automated landing

systemssystems TALS TALS

A Brief HistoryA Brief History June 1991Portable/panel mount GPS that interfaces with June 1991Portable/panel mount GPS that interfaces with

autopilotautopilot On February 10On February 10thth, 1993, the National Aeronautic Association , 1993, the National Aeronautic Association

selected the Global Positioning System Team as winners of selected the Global Positioning System Team as winners of the 1992 Robert J. Collier Trophy, the most prestigious the 1992 Robert J. Collier Trophy, the most prestigious aviation award in the United States. This team consists of aviation award in the United States. This team consists of researchers from the Naval Research Laboratory, the US Air researchers from the Naval Research Laboratory, the US Air Force, the Aerospace Corporation, Rockwell International Force, the Aerospace Corporation, Rockwell International Corporation, and IBM Federal Systems Company Corporation, and IBM Federal Systems Company

February 17, 1994 The Federal Aviation Administration February 17, 1994 The Federal Aviation Administration announces that GPS is operational an integrated as a part of announces that GPS is operational an integrated as a part of the U.S. air traffic control system. the U.S. air traffic control system.

In 1998, Vice President Al Gore announced plans to upgrade In 1998, Vice President Al Gore announced plans to upgrade GPS with two new civilian signals for enhanced user GPS with two new civilian signals for enhanced user accuracy and reliability, particularly with respect to aviation accuracy and reliability, particularly with respect to aviation safety. safety.

Wikipedia entry and http://www.aero.org/education/primers/gps/gpstimeline.htmlWikipedia entry and http://www.aero.org/education/primers/gps/gpstimeline.html

History continuedHistory continued

Originally only used by the military Originally only used by the military (Air Force), but the FAA has (Air Force), but the FAA has approved its use in commercial approved its use in commercial aviationaviation

Commercial GPS uses a different Commercial GPS uses a different frequency from the Air Force usesfrequency from the Air Force uses

First commercial GPS use in 1996First commercial GPS use in 1996

GPS in Commercial GPS in Commercial AviationAviation

““The objective of NAS Implementation is The objective of NAS Implementation is to develop the operational infrastructure to develop the operational infrastructure to support the certification process for to support the certification process for satellite navigation and provide the satellite navigation and provide the technical basis for the development of GPS technical basis for the development of GPS operational procedures for all phases of operational procedures for all phases of flight. NAS Implementation communicates flight. NAS Implementation communicates and cooperates with numerous and cooperates with numerous governmental and non-governmental governmental and non-governmental agencies to pave the way for a smooth agencies to pave the way for a smooth transition to satellite navigation.”transition to satellite navigation.” http://gps.faa.gov/programs/index.htm - National http://gps.faa.gov/programs/index.htm - National

Airspace SystemAirspace System

GoalsGoals Ultimately, the FAA, NAA, NAS, etc. wish Ultimately, the FAA, NAA, NAS, etc. wish

to have GPS-based aviation systems to have GPS-based aviation systems which operate all flightswhich operate all flights

Would create the possibility for “drone Would create the possibility for “drone commercial aviation” – highly unrealistic, commercial aviation” – highly unrealistic, but a rising possibilitybut a rising possibility

Would make it virtually impossible or Would make it virtually impossible or terrorists to hijack planes – although if terrorists to hijack planes – although if they ever did they could control every they ever did they could control every plane in the sky…plane in the sky…

Ethical problems? Economic problems? Ethical problems? Economic problems? Safety problems? All an issue…Safety problems? All an issue…

Improvements in Landing Improvements in Landing TechnologyTechnology

Selective Availability technology – used by the Selective Availability technology – used by the gov through 2000 – accuracy only to 100 gov through 2000 – accuracy only to 100 metersmeters

2001 – best non-SA accuracy only to 15 2001 – best non-SA accuracy only to 15 metersmeters

Differential GPS – used by the Gov until late Differential GPS – used by the Gov until late 2001 – up to10 meters accuracy2001 – up to10 meters accuracy

WAAS – still used by the gov – able to attain WAAS – still used by the gov – able to attain accuracy of up to 3 metersaccuracy of up to 3 meters

LAAS – developed in 2001 – current accuracy LAAS – developed in 2001 – current accuracy is 16 m laterally and 4 m vertically – but goal is 16 m laterally and 4 m vertically – but goal is go have both accuracies down to 1 meteris go have both accuracies down to 1 meter

Early GPS - ILSEarly GPS - ILS

Instrument Landing System Instrument Landing System 2 separate systems – one vertical guidance 2 separate systems – one vertical guidance

and one horizontal guidance systemsand one horizontal guidance systems Localizer antenna located at the end of the Localizer antenna located at the end of the

runway – 2 signals transmitted on a carrier runway – 2 signals transmitted on a carrier frequency between 108 MHz and 111.975 frequency between 108 MHz and 111.975 MHz MHz

Localizer receiver on the aircraft measures Localizer receiver on the aircraft measures difference in depth of modulation – when the difference in depth of modulation – when the difference is 0 the localizer is in line with the difference is 0 the localizer is in line with the center line of the runwaycenter line of the runway

ILS continuedILS continued

glideslope antenna array is sited to glideslope antenna array is sited to one side of the runway touchdown one side of the runway touchdown zone – follows the path of an aircraft zone – follows the path of an aircraft down the center of the runway down the center of the runway

The GS signal is transmitted on a The GS signal is transmitted on a carrier frequency between 328.6 carrier frequency between 328.6 MHz and 335.4 MHzMHz and 335.4 MHz

uses a technique similar to that of uses a technique similar to that of the localizer the localizer

ILS DiagramILS Diagram

ILS in UseILS in Use

Localizer Antenna at Whiteman Airforce Base

MLSMLS Microwave Landing System – developed by FAA Microwave Landing System – developed by FAA

NASA and the Department of DefenseNASA and the Department of Defense-“designed to provide precision navigation -“designed to provide precision navigation

guidance for exact alignment and descent of guidance for exact alignment and descent of aircraft on approach to a runway”aircraft on approach to a runway”

- provides azimuth (The angle of rotation - provides azimuth (The angle of rotation (horizontal) that a ground based parabolic (horizontal) that a ground based parabolic antenna ), elevation and distanceantenna ), elevation and distance

- supplements ILS – has both vertical and - supplements ILS – has both vertical and horizontal guidance systemshorizontal guidance systems

- MLS use suspended by FAA in 1994 in - MLS use suspended by FAA in 1994 in support of then new WAAS technologysupport of then new WAAS technology

MLS DiagramMLS Diagram

WAASWAAS ““WAAS is a GPS-based navigation and landing system WAAS is a GPS-based navigation and landing system

that is meant to improve safety by providing precision that is meant to improve safety by providing precision guidance to aircraft for all phases of flight at thousands guidance to aircraft for all phases of flight at thousands of airports and landing strips where there is no ground- of airports and landing strips where there is no ground- based landing capability. WAAS consists of 25 ground based landing capability. WAAS consists of 25 ground reference stations, 2 leased geostationary satellites, 2 reference stations, 2 leased geostationary satellites, 2 master stations, and 4 uplink stations. The ground master stations, and 4 uplink stations. The ground reference stations are strategically positioned across the reference stations are strategically positioned across the United States to collect GPS satellite data. WAAS is United States to collect GPS satellite data. WAAS is designed to improve the accuracy, integrity, and designed to improve the accuracy, integrity, and availability of information coming from GPS satellites availability of information coming from GPS satellites and to correct signal errors caused by solar storms, and to correct signal errors caused by solar storms, timing, and satellite errors. Unlike conventional ground-timing, and satellite errors. Unlike conventional ground-based navigation aids, WAAS provides curved precision based navigation aids, WAAS provides curved precision approach paths in order to avoid obstacles, restricted approach paths in order to avoid obstacles, restricted airspace, noise-sensitive areas, and congested airspace.”airspace, noise-sensitive areas, and congested airspace.” http://www.gao.gov/new.items/d0511.pdfhttp://www.gao.gov/new.items/d0511.pdf

How it WorksHow it Works 25 ground stations through out the United 25 ground stations through out the United

States – compare GPS signal with known States – compare GPS signal with known coordinatescoordinates

Report to WAAS Master Station – sends Report to WAAS Master Station – sends singal to WAAS satellitesingal to WAAS satellite

WAAS satellite sends signal back to planeWAAS satellite sends signal back to plane ““The WAAS-enabled GPS receiver adds the The WAAS-enabled GPS receiver adds the

correction factor to the GPS signals to correction factor to the GPS signals to derive a corrected GPS signal which is far derive a corrected GPS signal which is far more accurate than the original GPS signal.”more accurate than the original GPS signal.” http://gps.faa.gov/Programs/WAAS/waas.htmhttp://gps.faa.gov/Programs/WAAS/waas.htm

WAAS DiagramWAAS Diagram

History of WAASHistory of WAAS Developed by the DOT and the FAA in Developed by the DOT and the FAA in

early 1995early 1995 First precision approach technology was First precision approach technology was

Instrument Landing System – a glide path, Instrument Landing System – a glide path, laser guided systemlaser guided system

Soon replaced by MLS – Microwave Soon replaced by MLS – Microwave Landing System in the late 80’s which Landing System in the late 80’s which used microwaves to locate the aircraftused microwaves to locate the aircraft

Soon replaced by the highly more Soon replaced by the highly more accurate, and much cheaper WAAS accurate, and much cheaper WAAS systemsystem

More HistoryMore History

July 10, 2003 – WAAS signal July 10, 2003 – WAAS signal activated for general aviationactivated for general aviation

March 2005, FAA leases services of March 2005, FAA leases services of WAAS geostationary satellite from WAAS geostationary satellite from Lockheed Martin through 2016Lockheed Martin through 2016

2006 – WAAS available in 99% of the 2006 – WAAS available in 99% of the continental United Statescontinental United States

Problems with WAASProblems with WAAS

Signal often affected by cloudy weatherSignal often affected by cloudy weather Signal affected by “jamming” – not so Signal affected by “jamming” – not so

much a problem anymore with new much a problem anymore with new technologies, but was a problem at the technologies, but was a problem at the start of GPS landing systemsstart of GPS landing systems

System can only cover a limited System can only cover a limited amount of the country due to possible amount of the country due to possible receiver locations – however this receiver locations – however this percentage has reached 99% of the percentage has reached 99% of the countrycountry

LAASLAAS ““LAAS is a precision approach and landing LAAS is a precision approach and landing

system that relies on the Global Positioning system that relies on the Global Positioning System (GPS) to broadcast highly accurate System (GPS) to broadcast highly accurate information to aircraft on the final phases information to aircraft on the final phases of a flight. LAAS is being developed of a flight. LAAS is being developed specifically to augment GPS satellites to specifically to augment GPS satellites to support precision approaches and landing support precision approaches and landing capability to aircraft operating within a 20- capability to aircraft operating within a 20- to 30-mile radius of the airport. LAAS to 30-mile radius of the airport. LAAS approaches will be designed to avoid approaches will be designed to avoid obstacles, restricted airspace, noise-obstacles, restricted airspace, noise-sensitive areas, or congested airspace.”sensitive areas, or congested airspace.” http://www.gao.gov/new.items/d0511.pdfhttp://www.gao.gov/new.items/d0511.pdf

History of LAASHistory of LAAS Concept first in 1992Concept first in 1992 System requirements first analyzed in 2001 – System requirements first analyzed in 2001 –

developmental stage beginsdevelopmental stage begins Developed in late 2001Developed in late 2001 Due to be implemented in 2006, however due Due to be implemented in 2006, however due

to the FAA budget the project has been to the FAA budget the project has been deferred to 2009 deferred to 2009

Only 18 million left in the budget as of the end Only 18 million left in the budget as of the end of 2004 – will only carry LAAS development of 2004 – will only carry LAAS development through 2005 – implementation will require through 2005 – implementation will require 600 million dollars600 million dollars http://www.gao.gov/new.items/d0511.pdfhttp://www.gao.gov/new.items/d0511.pdf

How it WorksHow it Works ““The Local Area Augmentation System The Local Area Augmentation System

(LAAS) will augment the Global (LAAS) will augment the Global Positioning System to provide an all-Positioning System to provide an all-weather approach, landing, and surface weather approach, landing, and surface navigation capability. LAAS focuses its navigation capability. LAAS focuses its service on a local area (approximately a service on a local area (approximately a 20-30 mile radius), such as an airport, 20-30 mile radius), such as an airport, and broadcasts its correction message via and broadcasts its correction message via a very high frequency (VHF) radio data a very high frequency (VHF) radio data link from a ground-based transmitter.”link from a ground-based transmitter.” http://gps.faa.gov/Library/laas-f-text.htmhttp://gps.faa.gov/Library/laas-f-text.htm

LAAS DiagramLAAS Diagram

Problems with LAASProblems with LAAS Only covers 20-30 miles around a single Only covers 20-30 miles around a single

airport – WAAS covers much more of the airport – WAAS covers much more of the country and is much more effectivecountry and is much more effective

VHF uplink signal currently slated to VHF uplink signal currently slated to share the frequency band from 108 MHz share the frequency band from 108 MHz to 118 MHz with existing ILS localizer – to 118 MHz with existing ILS localizer – users will have to own more than one set users will have to own more than one set of radio gear to operate the systemof radio gear to operate the system

potential for a single point of failure – potential for a single point of failure – caused by weather, solar activity, or caused by weather, solar activity, or jamming – airports with LAAS have no jamming – airports with LAAS have no back up…if the system goes you’re out of back up…if the system goes you’re out of luck!luck!

Automated LandingsAutomated Landings

Auto-pilot can already do take-offs, and Auto-pilot can already do take-offs, and in-flight performance – the one untested in-flight performance – the one untested area is landingsarea is landings

When automated landings are perfected, When automated landings are perfected, un-piloted flights may become a reality.un-piloted flights may become a reality.

LAAS has brought automated landings LAAS has brought automated landings into possibility – with 1 meter accuracy into possibility – with 1 meter accuracy as opposed to the 100 meter accuracy of as opposed to the 100 meter accuracy of less than 15 years agoless than 15 years ago

Possibilities with WAAS and Possibilities with WAAS and LAASLAAS

WAAS and LAAS, or a combination of the two WAAS and LAAS, or a combination of the two are bringing ever closer the idea of are bringing ever closer the idea of unmanned flight – both in the military and unmanned flight – both in the military and civilian realmscivilian realms

Greatly reduces the risk of terrorism Greatly reduces the risk of terrorism involving planes, but also puts human lives in involving planes, but also puts human lives in the hands of robotsthe hands of robots

Not yet at the level where we can abandon Not yet at the level where we can abandon pilotspilots

New LAAS system – if it is ever implemented New LAAS system – if it is ever implemented would make it possible to have un-piloted would make it possible to have un-piloted flightsflights

To SummarizeTo Summarize

- Technology has gotten much better Technology has gotten much better in the past 10 yearsin the past 10 years

- LAAS accuracy can not be beat, but LAAS accuracy can not be beat, but WAAS coverage can not be beat, WAAS coverage can not be beat, thus…thus…

- Final system likely to have LAAS at Final system likely to have LAAS at major airports with WAAS around major airports with WAAS around the rest of the countrythe rest of the country

Auto-landings history Auto-landings history (Military)(Military)

In 1947, The UK Blind Landing Experimental Unit (BLEU) was In 1947, The UK Blind Landing Experimental Unit (BLEU) was established within the Royal Aircraft Establishment, now QinetiQ. established within the Royal Aircraft Establishment, now QinetiQ. BLEU conducted the world’s first fully automatic landing in 1950 BLEU conducted the world’s first fully automatic landing in 1950 and had significant involvement in the development programme and had significant involvement in the development programme for the world’s first Cat IIIb landing system for civil airliners. for the world’s first Cat IIIb landing system for civil airliners.

Later technology developed by QinetiQ's predecessor include the Later technology developed by QinetiQ's predecessor include the Microwave Aircraft Digital Guidance Equipment (MADGE), Microwave Aircraft Digital Guidance Equipment (MADGE), developed as a tactical approach and landing system and was developed as a tactical approach and landing system and was subsequently adopted by the Royal Navy for precision recovery of subsequently adopted by the Royal Navy for precision recovery of aircraft to the INVINCIBLE class aircraft carriers. aircraft to the INVINCIBLE class aircraft carriers.

Recent work by QinetiQ's forebears on automatic landing systems Recent work by QinetiQ's forebears on automatic landing systems has focussed on the use of differential and relative-GPS systems. has focussed on the use of differential and relative-GPS systems. A number of flight trials were conducted during the 1990s to A number of flight trials were conducted during the 1990s to explore the use of GPS as a means for recovery of helicopters to explore the use of GPS as a means for recovery of helicopters to restricted sites, concentrating particularly on ship operations. restricted sites, concentrating particularly on ship operations.

QinetiQ's recent ship trial aboard HMS INVINCIBLE has QinetiQ's recent ship trial aboard HMS INVINCIBLE has demonstrated the world’s first fully automatic STOVL shipboard demonstrated the world’s first fully automatic STOVL shipboard recovery and landing.recovery and landing.

Taken from http://www.qinetiq.com/home/newsroom/news_releases_homepage/2005/2nd_quarter/Taken from http://www.qinetiq.com/home/newsroom/news_releases_homepage/2005/2nd_quarter/QinetiQs_JSF_world_first.htmlQinetiQs_JSF_world_first.html

Automated Landing Automated Landing Systems – Big NewsSystems – Big News

““September 25, 2002 -- San Diego, California. General September 25, 2002 -- San Diego, California. General Atomics Aeronautical Systems, Inc., the leading Atomics Aeronautical Systems, Inc., the leading manufacturer of unmanned aircraft systems, has manufacturer of unmanned aircraft systems, has successfully landed its IGNAT unmanned aircraft using a successfully landed its IGNAT unmanned aircraft using a company-developed automatic landing system. company-developed automatic landing system. Aeronautical Systems has funded and has now fully Aeronautical Systems has funded and has now fully demonstrated the capability of automatically landing its demonstrated the capability of automatically landing its aircraft without the direct control of the pilot. The aircraft without the direct control of the pilot. The automatic landing software uses differential global automatic landing software uses differential global positioning system (GPS) which provides an accurate positioning system (GPS) which provides an accurate cross section of where the aircraft is in space and in cross section of where the aircraft is in space and in relation to the ground. Using this formula, the aircraft relation to the ground. Using this formula, the aircraft descends at a pre-programmed rate to a fixed point on the descends at a pre-programmed rate to a fixed point on the ground. This company-funded effort resulted in the first ground. This company-funded effort resulted in the first automatic landing of the IGNAT on 12 September.”automatic landing of the IGNAT on 12 September.” http://www.ga.com/news.php?http://www.ga.com/news.php?

subaction=showfull&id=1032940800&archive=&start_from=&ucsubaction=showfull&id=1032940800&archive=&start_from=&ucat=1&heat=1&he

New Landing SystemsNew Landing Systems ““the means for guiding and controlling the means for guiding and controlling

aircraft from an initial approach altitude to a aircraft from an initial approach altitude to a point where safe contact is made with the point where safe contact is made with the landing surface. Such systems differ from landing surface. Such systems differ from low-approach systems in three major low-approach systems in three major respects: (1) They furnish not only guidance respects: (1) They furnish not only guidance but control of the aircraft as well. (2) They but control of the aircraft as well. (2) They furnish information on the aircraft's position furnish information on the aircraft's position with respect to the terrain below it, and the with respect to the terrain below it, and the rate at which the landing surface is being rate at which the landing surface is being approached. (3) They do not require the pilot approached. (3) They do not require the pilot to assume manual control near the ground”to assume manual control near the ground” http://www.accessscience.com/Encyclopedia/http://www.accessscience.com/Encyclopedia/

0/06/Est_063500_frameset.html?doi0/06/Est_063500_frameset.html?doi

TALSTALS

Tactical Automated Landing System – Tactical Automated Landing System – currently the only commercially-oriented currently the only commercially-oriented automated landing systemautomated landing system Not available for commercial use but currently Not available for commercial use but currently

in development for commercial usein development for commercial use Designed by the army to reduce dangers of Designed by the army to reduce dangers of

landing at night, but becoming more and more landing at night, but becoming more and more commercially orientedcommercially oriented

Could be used in planes as early as 1212 – Could be used in planes as early as 1212 – radar landing system dependent on LAAS radar landing system dependent on LAAS technologytechnology