Posted on 06/24/2009 8:17:23 AM PDT by pabianice
I still remember when they tested SATNAV on our old ATF. I think it was called the SRN-19. Nice, huge, and often would fail to capture enough sats for the required time to give a fix.
And yes, we still met with the XO at sunset to shoot the stars, although I was never good at that!
Using the sextant aboard a P-3. Stand on seat. Put left knee on top of seat, next to head rest. Hold sextant with inboard hand. Put outboard hand on anything reachable for steadying. Hold cel body in bubble for two minutes as timer runs. Curse pilots for heading changes after you told them you need a constant heading for shoot. Fall off seat in turbulence, spraining something. Curse pilot again. Plot lines of position. Curse as triangle is size of Rhode Island. Shoot again. Timer fails. Curse some more; put ice on sprain. Repeat every 20 minutes for 11 hours.
The author is not properly up to date. GPS now has WAAS, an augmentation system consisting of additional GPS ground stations and satellites. It is no longer only a Navstar/GPS satellite constellation.
The Federal Radionavigation Plan calls for the decommissioning of NDBs, VORs, TACANs, and eventually, ILS. LORAN has been the intended backup for GPS, with over $160 million already spent to complete the upgrades required for eLORAN- a greatly enhanced version.
eLORAN offers accuracy close to GPS, can work under tree canopies and even inside buildings, and is extremely difficult to maliciously jam (unlike GPS). Being ground-based, LORAN stations are far less vulnerable and costly than the GPS satellites.
Terminating eLORAN is a huge waste of an investment already made, and will leave pilots, commercial users, and telecom providers with no backup whatsoever to GPS, and has significant national security implications.
Terminating LORAN is incredibly shortsighted, and a very bad idea.
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