1. © David Last Resilient PNT Forum V Helsinki, Finland 30 May 2016 Resilient PNT: Time for a Change Professor David Last Past-President, Royal Institute of Navigation Picture: earthobservatory.nasa. gov//newsroom/BlueMarble/

3. The founders of Chronos and UrsaNav have formed a new collaboration … in the UK and the USA … to enhance the resilience and reliability of the many economic and business models that depend on space-based timing and positioning services.

4. Low-frequency eLoran transmissions from Anthorn in (the) UK will continue despite the switch off of the legacy Loran-C transmissions by the French, Norwegians, Danes and Germans. Signals from the Russian Loran-C equivalent … are still available.

5. Sources: bbc.co.uk, chronos.co.uk, gpsworld.com

6. Navigation or Timing – or even Data? Old model: Focus is on navigation Stations owned by governments Stations operated by governments Stations paid for by governments By-products: precise timing; robust data; land navigation Navigation carries all costs Services free to all New model: Focus is on precise timing Stations owned by governments Stations operated commercially Stations paid for by users Additional services: robust data, maritime and land navigation Costs spread across services Basic service free, licences for Precise services and equipment

7. Picture: Caverly, James, “GPS Critical Infrastructure Usage/Loss Impacts/Backups/Mitigation,” http:// www.swpc.noaa.gov/sites/default/files/images/u33/GPS-PNTTimingStudy-SpaceWeather4-27.pdf. Timing Requirements of US Critical Infrastructure and Key Resources

8. GPS Timing Receiver Pictures: Charles Curry, ‘Time from the sky’, http://www.chronos.co.uk/index.php/en/news-and-pr/news-page/1620-time-from-the-sky-insight-into-gps GPS timing is locked to the US Naval Observatory Master Clock

9. Picture: Caverly, James, “GPS Critical Infrastructure Usage/Loss Impacts/Backups/Mitigation,” http:// www.swpc.noaa.gov/sites/default/files/images/u33/GPS-PNTTimingStudy-SpaceWeather4-27.pdf. Timing Requirements of US Critical Infrastructure and Key Resources

10. Picture: Charles Curry, ‘Delivering a National Timescale Using eLoran’ https://rntfnd.org/wp-content/uploads/Delivering-a-National-Timescale-Using-eLoran-Ver1-0.pdf. Maximum Time Interval Error (MTIE) diagram. To meet the Primary Reference Clock standard, the measurements must lie below mask marked with dots. Blue: GPS timing. Red: eLoran timing.

11. Picture: Charles Curry, ‘Time from the sky’, http://www.chronos.co.uk/index.php/en/news-and-pr/news-page/1620-time-from-the-sky-insight-into-gps. GPS antenna on the roof of a tall building

12. Pictures: www.insidegnss.com, http://rntfnd.org/2016/04/21/us-govt-touts-eloran-at-ny-stock-exchange/.

13. Pictures: http://www.ursanav.com/wp-content/uploads/Resilient-Timing-and-UTC-Service.pdf/ Basic eLoran timing service from four stations (within 1 microsecond of UTC) Precision eLoran timing service from four stations and 71 differential sites (within 100 nanoseconds of UTC)

14. Picture: General Lighthouse Authorities of the United Kingdom & Ireland Anthorn is currently delivering UTC-locked timing to a population of approximately 165 million living in 10 countries.

15. © David Last Resilient PNT Forum V Helsinki, Finland 30 May 2016 Resilient PNT: Time for a Change Professor David Last Past-President, Royal Institute of Navigation Picture: earthobservatory.nasa. gov//newsroom/BlueMarble/