presented to: by: date: federal aviation administration space-based navigation systems sun-n-fun...

Presented to:

By:

Date:

Federal AviationAdministrationSpace-Based

Navigation Systems

Sun-N-Fun

Larry Oliver – Flight Standards (AFS-430)

April 2006

Space-based Navigation Systems2Federal Aviation

AdministrationApril 2006

Agenda

• Review of GPS basics

• Development of Wide Area Augmentation System (WAAS) and Local Area Augmentation System (LAAS)

• Performance based navigation

• What are we doing? (Future forecast)



Global Positioning System (GPS)

• Comprised of 24 satellites

– Transmitting on the same frequency

• Currently more satellites

– Due to outliving original life expectancy

• Designing third generation satellite (2015) (dual frequency)

• Satellites broadcast signal; receiver captures and develops pseudorange position information



Your GPS

Receiver

Navigator

Database



Why Are We Going to GPS?

• Performance

• Cost

• Reliability

• Better use of space

– Routes

– Terminal area

– Arrivals/Departures



Angular (VOR) vs Linear

• Accuracy of a linear system versus angular

• No need to buy real estate on mountain tops for VORs

• No need to buy real estate 7 miles from runway end for OM Global system

Accuracy decreases with distance

Accuracy constant

VOR

GPSRoute

VOR or GPS RWY 27 Lakeland, Florida



Receiver Autonomous Integrity Monitor (RAIM)

• Outages may occur due to

– Insufficient number of satellites in view

– Unsuitable satellite geometry

– Aircraft pitch/bank angle (antenna blockage)

• RAIM predictions consider satellite outages/geometry

• You should do RAIM predictions for ETA



Pilot Limitations of GPS

• TSO-C129: Airborne Supplemental Navigation Equipment Using GPS

• TSO-C145: Airborne Navigation Sensors Using GPS Augmented by WAAS

• TSO-C146: Stand-Alone Airborne Navigation Equipment Using GPS Augmented by WAAS



Wide Area Augmentation System (WAAS)• System of ground based

receiver sites in North America

• Measure system error• Transmit data to a WAAS

Master Station (WMS)• Uplink to a geostationary satellite• Satellite transmits back to aircraft

– Accuracy typically within 2-3 meters• Excellent vertical accuracy

• LPV approaches down to 200 feet



LPV Approach

• Localizer performance with vertical guidance

• Looks and flies like an ILS

• Maintained in your onboard database

• Minimums as low as 200 feet AGL

– Visibility determined by airfield infrastructure

RNAV (GPS) Z RWY 7L Daytona Beach, Florida



Local Area Augmentation System (LAAS)

• Benefits of LAAS– Achieve ILS CAT II/III minima– Reduced infrastructure– Single system for all runway ends– Guided missed approaches– Flexibility in sequencing– Tighter spacing due to more accurate navigation– Parallel simultaneous instrument approach

procedures



Moving Toward a Performance-Based National Airspace System

• What is performance-based navigation?

• What kind of equipment will be used?

• When will it occur?



Required Navigational Performance (RNP)

Required Navigation Performance (RNP) is a critical component of the movement toward performance-based navigation in the National Airspace System. RNP is a concept of area navigation (RNAV) operations in which the aircraft navigation system provides containment, monitoring and alerting for flight within a given airspace.



Relevant FAA Documents

• TSO-C129• TSO-C145• TSO-C146• AC 90-94• AC 20-138• AC 90- (RNP)• Aeronautical Information Manual



Conclusions

• Major changes are underway!– Old nav aids will go away– Reliance on GPS will increase– New capabilities will be added

• Adding new airplanes and increasing number of flights– But new airports/runways will be rare

RNAV (RNP) RWY 19 Washington Reagan