International Loran Association Conference Boulder, Colorado 4 November 2003

1. Ongoing Loran Evaluations at theFederal Aviation Administration and theUS Coast GuardMitchell J. NarinsSystems EngineerFederal Aviation AdministrationNavigation Integrated Product Team International Loran Association Conference Boulder, Colorado 4 November 2003

2. Purpose of the Evaluations • To determine whether an enhanced Loran system can provide the: • Accuracy • Availability • Integrity • Continuity a) to support Lateral Navigation through all phases of flight – including Non-Precision Approach (NPA) b) to support Harbor Entrance and Approach (HEA) for maritime users • To determine what other ancillary benefits can be derived from the continued provision of enhanced Loran services • e.g., to support Stratum 1 timing and frequency users • To determine if providing these services via Loran is cost-beneficial (i.e., Benefits/Costs >1)

3. New SSX Stations: 1 US TTX Stations: 11 US, 1 Canadian SSX Stations: 13 US, 4 Canadian LSU Control Stations North American Loran System First New SSX Station Installation George, Washington

4. Program Participants • Government • FAA • Navigation and Landing Systems Engr, AND-740 • Navigation and Landing System Architecture, ASD-140 • CNS Test and Evaluation, ACB-440 • Flight Standards, AFS-400 • Aircraft Certification, AIR-130 • Special Programs, AVN-5 • US Coast Guard • HQ Aids to Navigation • Navigation Center • Loran Support Unit • Command and Control Center • Volpe National Transportation System Center

5. Industry Booz|Allen|Hamilton Free Flight Systems* Illgen Simulation Technologies, Inc. JJMA Locus, Inc. Megapulse, Inc. Peterson Integrated Geopositioning Reelektronika* Rockwell Collins Timing Solutions Si-Tex Marine* WR Systems Academia Ohio University Stanford University US Coast Guard Academy University of Rhode Island University of Alaska University of Wales* Program Participants *New FY 2003 Team Member

6. Loran Program Logo Collection Booz|Allen|Hamilton

7. 4 November: Loran Integrity Certification Dr. Per Enge, Stanford University Loran of the 21st Century CAPT Tom Gunther (USCG Ret.), Booz|Allen|Hamilton Loran-C Maintenance Support CDR John Macaluso, Loran Support Unit The Challenge of Finding Your Way in a World Hostile to Radio Navigation Dr. Durk Van Willigan On-air with the New Solid State Transmitter CDR Chuck Teaney (USCG Ret.) WR Systems The Case for Transitioning to Time of Emission Control in the US CAPT Curt Dubay, USCG Navigation Center Loran Operation Performance Report LCDR Max Caruso, USCG NavCen Detachment Supporting the Enhanced Loran-C System LT (jg) Zach Conover, Loran Support Unit Applications of Differential Loran CDR Doug Taggert (USCG Ret.), Overlook Systems Differential Loran CAPT Ben Peterson (USCG Ret.), Peterson Integrated Geopositioning Common-View LORAN-C for Precision Time and Frequency Recovery Dr. Tom Celano, Timing Solutions Corporation Predicted Differential Loran Performance in Boston Harbor Mr. Andre Grebnev, Megapulse, Inc. 5 November: Early Skywave Propagation Dr. Peter Morris, Northrup Grumman Early Skywave Examples from PCMS Data CAPT Bob Wenzel (USCG Ret.), Booz|Allen|Hamilton Mitigation of the Effects of Early Skywave CAPT Ben Peterson (USCG Ret.), PIG Getting a Bearing of ASF Directional Corrections CAPT Dick Hartnett, USCG Academy Modelling Loran-C Envelope-to-Cycle Differences in Mountainous Terrain Dr. David Last, University of Wales – Bangor Summer Vacation 2003 – ASF Spatial Mapping in CO/AR/FL/CA Mr. Greg Johnson, JJMA Analysis of Groundwave Propagation Effects for Loran RNP 0.3 Dr. Sherman Lo, Stanford University 6 November Loran-C Band Data Collection Efforts at Ohio University Mr. Curt Cutright, Ohio University Atmospheric Noise Analysis Mr. Lee Boyce, Stanford University FAA Tests and H-Field Antenna to Increase Loran-C Availability During P-Static Mr. Robert Erikson, FAA Technical Center Integrated GPS/Loran Navigation Sensor for Aviation Applications Mr. James Doty, Rockwell Collins Development of an Integrated GPS/LORAN Prototype Navigation System for Business and General Aviation Applications Dr. James Davis, Free Flight Systems Integrated GPS/ Loran Sensor for Maritime Operations Mr. Wouter Pelgrum, Reelektronika On Non-iterative Loran-C Time Difference to Latitude/Longitude Converters Dr. Paul Williams, University of Wales - Bangor Team Contributions to ILA 2003 • The U.S. Loran-C Evaluation Program has much to be proud of…and equally much to report out at this ILA Conference:

8. Loran-C Evaluation Program • FY 1994 • Federal Radionavigation Plan (FRP) announced that Loran-C service would terminate 31 December 2000 • Congressional lobbying (primarily by aviation groups) resulted in budgetary language to continue system development • FY 1997 ($4.6 M) • Congressional Mandate • The FY 1997 Congressional budget provided funds to the FAA for “upgrades to the Loran-C navigation system and... to implement an automatic blink system (ABS).” • FY 1998 ($3 M) • Congressional Mandate • The FY 1998 Congressional budget directed the FAA “to continue Loran-C upgrades initiated in fiscal 97.” • FY 1999 ($7 M) • Congressional Mandate • The Congressional budget provided funds to the FAA for “further development of the Loran-C navigation system.”

9. Loran-C Evaluation Program • FY 2000 ($10 M) • Congressional Mandate • The Congressional budget provided funds to the FAA for “further development of the Loran-C navigation system.” • FY 2001 ($20 M requested, $25 M provided) • First year included in President’s budget • FY 2002 ($13 M requested, $19 M provided) • FY 2003 ($13 M requested, $25 M provided) • FY 2004 ($0 requested, $20M - $25M expected) • Senate (Appropriations Report) raised the level of funding to $20 Million • House (Appropriations Report) raised the level of funding to $25 Million • Awaiting Conference Decision

10. A Most Substantial Investment * *Assumes $25 M in FY 04

11. Current US Loran-C Policy “While the Administration continues to evaluate the long-term need for continuation of the Loran-C radionavigation system, the Government will operate the Loran-C system in the short term. The U.S. Government will give users reasonable notice if it concludes that Loran-C isnot neededor isnot cost effective, so that users will have the opportunity to transition to alternative navigation aids. With this continued sustainment of the Loran-C service, users will be able to realize additional benefits. Improvement of GPS time synchronization of the Loran-C chains and the use of digital receivers may support improved accuracy and coverage of the service. Loran-C will continue to provide a supplemental means of navigation. Current Loran-C receivers do not support nonprecision instrument approach operations.” • 2001 US Federal Radionavigation Plan

12. Volpe GPS Vulnerability Study • The vulnerability study released on 10 September 2001 recognized the potential for Loran-C to be a robust backup system for GPS navigation and augmentation and timing. • “In an effort to provide the greatest benefit to the users, encourage the development of affordable vehicle-based backup such as GPS/inertial receivers, and, in the event Loran-C becomes a viable terrestrial backups to GPS, aviation certifiable Loran-C receivers, and GPS/Loran-C receivers.” • “Conduct a comprehensive analysis of GPS backup navigation and precise timing options including VOR/DME, ILS, Loran-C, inertial navigation systems, and operating systems. • “Continue the Loran-C modernization program of the FAA and USCG, until it is determined whether Loran-C has a role as a GPS backup system. If it is determined that Loran-C has a role in the future navigation mix, DOT should promptly announce this to encourage the electronics manufacturing community to develop new Loran-C technologies.”

13. Loran’s Potential as a GPS Backup ParameterLoranGPS • Frequency 100 kHz 1.2-1.5 GHz • Propagation Groundwave Line of Sight • Chief Propagation Errors Conductivity, troposphere Iono delay variations* variations • Penetration Walls, ground, 6' seawater Very little penetration • Modulation TD + CD Spread spectrum CD • Coverage To ground level To ground level • Signal Strength Relatively high Very low by design • Timing Basis Triple Cesium Rubidium at present • Tx Location Ground - stationary Space - moving • Utility: Aviation example En route, terminal airspace En route, terminal airspace Lateral-guided approach Lateral-vertical approach** • User communities Multiple (air, land, marine) Multiple ( air, land, marine) * Propagation errors are affected at different times and places by components of solar storms * GPS propagation variations are not correlated with Loran-C propagation errors. ** Vertical-guided "precision" approaches require WAAS or LAAS augmentations.

14. Loran-C NavigationCurrent Capabilities/Future Needs* Note: Most stringent requirements shown in aviation orange. * Includes Stratum 1 timing and frequency capability.

15. 0.1 ns 1 ns 10 ns 100 ns 1 µs 10 µs 100 µs 1 ms 10 ms 100 ms 1 s PTTI/R&D - NIF Scientific/ Experimental • High Precision Military • GPS Monitor Stations • GPS Weapons • AT3 Airborne Geolocation Demo • Bistatic Radar • Other Applications National Timing Labs Advanced Comms • Power Systems • Fault Location • Phasor Meas • Data Sharing CDMA2000 - Base Stations • Low Precision Military • Ground Terminals • VHF Special Comms • Wide Area Data Logging • Seismic monitoring • Nuclear Blast Detection • Digital Time Servers • NTP, etc Timing user survey not intended to be a complete representation of all users. Requirements have been generalized and averaged over user groups Astronomy • Authentication • Internet login Financial Transactions Could be served by Enhanced LORAN (eLoran) Timing User Spectrum

16. 10-15 10-14 10-13 10-12 10-11 10-10 10-9 10-8 10-7 10-6 10-5 VLBI National Timing Labs • High Precision Military • GPS Monitor Stations • Various Applications • High Precision Metrology • Equipment Calibration • Stratum 1 Comms • Telcos • Military GT • Digital Wideband CDMA2000 - Base Stations • Low Precision Metrology • Equipment Calibration • Low Precision Military • Combat Control Systems • Oscillator Manufacturers • Cal of low-cost xtal • Misc • Broadcast TV • Digital Modular Radio • IEEE P802.16 Wireless Frequency user survey not intended to be a complete representation of all users. Requirements have been generalized and averaged over user groups Could be served by eLORAN Frequency User Range

17. Status of theOngoing Loran Evaluation and Associated System Recapitalization • Accuracy • Availability • Integrity • Continuity Final Report due to the Departments of Transportation and Homeland Security March 2004

18. Loran Evaluation Activities • To determine Loran Accuracy Potential: • ASF* studies and calibration (for both conductivity and terrain) • Receiver/Integrated receiver studies • Loran Accuracy Performance Panel (LORAPP) • Differential Loran study • To determine Loran Availability Potential: • H-Field Antenna/P-static testing • CONUS All-in-view receiver analysis • Noise analysis • SSX and TFE modification evaluations • To determine Loran Integrity Potential: • Loran Integrity Performance Panel (LORIPP) • Time of Transmission/ASF studies • To determine Loran Continuity Potential: • Receiver/Integrated receiver/antenna studies *additional secondary factors

19. Loran Issue 1: Accuracy • Current Accuracy: 0.25 nm, 2drms, 95% • Target Accuracy (NPA): 0.16 nm (307 m) - RNP 0.3  0.43 nm (802 m) - RNP 0.5 • Target Accuracy (HEA): 8 – 20 m, 2drms, 95% IssuesPotential Mitigations • Old timing sources New cesium clocks • Old timing equipment New timing suite • Tube technology Solid State Transmitter (SSX) technology • Simple propagation model New ASF* tables/algorithms • No real-time corrections LORAPP (Differential Loran) *additional secondary factors

20. Flights to Support Characterization of ASFsAugust 2002 and March 2003

21. Loran 2 Loran 7 Loran 7 Loran 1 ~9.0 m ~3.0 m GPS 1 GPS 7 Loran 3 GPS 8 ~6.0 m GPS 3 Loran 8 GPS 2 GPS 7 ~13.0 m ~6.5 m ~2.0 m Typical Results NPA Requirement: 307 m!

22. Flights to Support Characterization of ASFs July – September 2003

23. Grand Junction, Colorado Little Rock, Arkansas Monterey, California Pensacola/Destin, Florida Loran ASF Measurement CampaignLots of Miles – Lots of Data

24. Loran Issue 2: Availability • Current Availability:0.997 • Target Availability (NPA): 0.999 - 0.9999 • Target Availability (HEA): 0.997 – 0.999  IssuesPotential Mitigations • Precipitation Static H-Field Antenna* • Atmospheric Noise H-Field, AIV Receiver • Loss of Station Power UPS • Lightning New Lightning Protection • Chain/Stick Availability All-in-view receivers • Tube overloads Solid State Transmitters *Awaiting safety certification

25. Loran Issue 3: Integrity • Current Integrity: 10 sec. alert @ + 100ns or other specified error conditions • Target Integrity (NPA): 0.9999999* 556m HPL, 10 sec. alert • Target Integrity (HEA): 0.99997** IssuesPotential Mitigations • Presumed Integrity/ Loran Integrity Panel (LORIPP) Auto Blink System Loran Accuracy Panel (LORAPP) *For Aviation: The probability of providing Hazardous or Misleading Information (HMI) is 1 x 10-7 **For Maritime: The probability of providing Hazardous or Misleading Information (HMI) is 3 x 10-5

26. Loran Issue 4: Continuity • Current Continuity: 0.997 • Target Continuity (NPA): 0.999 - 0.9999 • Target Continuity (HEA): 0.9985 – 0.9997 IssuesPotential Mitigations Same as Availability plus: • Receiver acquisition time New DSP technology New SSX Switch Units AIV/Integrated Receiver

27. Prototype Brassboard Locus Loran Card Installed in Rockwell Collins Multi-Mode Receiver • Flight Testing Results will be reported out on Thursday • Integrated GPS/Loran receiver for general aviation also being developed by Free Flight Systems and Locus

28. FreeFlight/Locus GA Multi-Mode Receiver • Similar to GPS/WAAS/Loran MMR development • Phase I Prototype testing of Integrated GPS/WAAS/Loran receiver testing to commence this fall

29. FreeFlight/Locus GA Multi-Mode Receiver • Phase II Prototype to be available for testing Spring 2004

30. Signal Processor77 x 51 mm Front End & ADC77 x 47 mm Megapulse/Reelektronika/Si-TekMulti-Mode Marine Receiver

31. The Loran Decision Process • What are we doing? • When are we doing it? • When will we be finished? • When will there be a decision? Final Report due to the Departments of Transportation and Homeland Security March 2004

32. Determine if Loran can provide the accuracy, availability, integrity, and continuity to support non-precision approach for aviation and harbor entrance and approach for maritime. Determine if Loran can provide benefits to timing and frequency users. Determine if Loran can provide navigation, timing, and frequency benefits in a cost effective manner (i.e., B/C >1.0). Review results of evaluation and make recommendation to Secretary of Transportation. Announce US Gov’t Decision regarding future of Loran. Loran Evaluation Team will provide report to the Department of Transportation NLT 31 March 2004. Loran Evaluation Team will provide report to the Department of Transportation NLT 31 March 2004. Loran Evaluation Team will provide report to the Department of Transportation NLT 31 March 2004. Positioning and Navigation (PosNav) Committee of the Department of Transportation Secretary of Transportation The Loran Decision Process Action Responsibility

33. The Loran Decision Process LORIPP LORAPP Loran Evaluation Team compiles technical findings and BCA Data into Draft Report December 2003 Internal FAA Review Loran Evaluation Team compiles comments into Final Report March 2004 Internal USCG Review Department of Homeland Security PosNav Committee members review the report Volpe FAATC PosNav Committee meets to discuss report findings and determine what recommendation should be forwarded to The Secretary of Transportation Secretary of Transportation Announces Decision PosNav Committee recommends decision to SecDOT

34. Department of Transportation Pos/Nav Committee • Hon. Jeffrey Shane, Undersecretary of Transportation for Policy, Chairman • Members • Federal Aviation Administration • Federal Highway Administration • Federal Motor Carrier Safety Administration • Federal Railroad Administration • Federal Transit Administration • Maritime Administration • National Highway Traffic Safety Administration • Saint Lawrence Seaway Development Corporation • Surface Transportation Board • Research and Special Programs Administration • US Coast Guard • US Department of Commerce (Geodetic Survey/Weather/Time) • US Department of Defense • US Department of Homeland Security (?)

35. Summary • FY ’03 – Team continued its excellent progress • FY ’04 – Work continues: • Development of multi-mode receivers for aviation and maritime users • Development of ASF models that include spatial factors based on both conductivity and terrain factors and temporal factors based on multiple seasonal measurements to support NPA • Design and development of differential Loran system and means to transmit ASF “corrections” to users to support HEA • Test of Differential Loran • Completion of timing and frequency testing to determine potential level of support to user communities • Completion of Benefit/Cost Analysis • Completion of p-static testing • Completion of LORIPP and LORAPP activities • Publication of evaluation report • US Government Loran Decision

36. Questions

37. Aviation Requirements: RNP* 0.3 (target); RNP* 0.5 (minimum) Performance RequirementValue • Accuracy (target) 307 metersAccuracy (minimum) 802 meters • Alarm Limit (target) 556 metersAlarm Limit (minimum) 926 meters • Integrity 10-7/hour • Time-to-alarm 10 seconds • Availability (minimum) 99.9%Availability (target) 99.99% • Continuity (minimum) 99.9%Continuity (target) 99.99% (Source: FAA Loran Evaluation Report, June 2002) *Required Navigation Performance

38. Marine HEA Requirements (Primary) Performance RequirementValue • Accuracy (target) 10 meters, 95%Accuracy (threshold) 20 meters, 95% • Alarm Limit (target) 25 metersAlarm Limit (threshold) 50 meters • Integrity (target) 3x10-5 • Time-to-alarm 10 seconds • Availability (threshold) 99.7%Availability (target/VTS) 99.9% • Continuity (threshold) 99.85% over 3 hours Continuity (target) 99.97% over 3 hours (Sources: FRP, DOT Task Force, TASC DGPS Mission Needs Analysis: Harbor Entrance and Approach, IMO Resolutions A.815(19) and draft revisions to A.860(20))

39. Marine HEA Requirements (Backup) Performance RequirementValue • Accuracy (backup) 20 meters, 95% • Alarm Limit (backup) 50 meters • Integrity (target) 3x10-5 • Time-to-alarm 10 seconds • Availability (minimum) 99.7% • Continuity (minimum) 99.85% (over 3 hours) (Sources: FRP, DOT Task Force, TASC DGPS Mission Needs Analysis: Harbor Entrance and Approach, IMO Resolutions A.815(19) and draft revisions to A.860(20))

40. Timing and Frequency Specifications Performance SpecificationValue • Frequency Accuracy (threshold) 1 in 1012 (averaged over 24 hrs) • No External Antenna (desired) • Backward Compatibility (desired) • Integrity Data Minimum of USE/NO USE Flag • Higher Accuracy Time of Day Time Tag (Year/DOY/Second) Leap Second information • Timing Accuracy <100nsec • Differential Data Daily Correction (Source: DOT Task Force, T1X1 letter of Oct 2002)