1 July 2011
Overlooking such inferior systems as CONSOLAN (http://www.answers.com/topic/consolan) and OMEGA (http://en.wikipedia.org/wiki/Omega_Navigation_System) , we had another existing navigation system called LORAN (http://en.wikipedia.org/wiki/LORAN) for Long Range Navigation). Developed following World War Two, and consistently upgraded, LORAN used a very low frequency signal to place an airplane or ship within several hundred feet of a desired location. This resulted in what navigators call a Fix – a known position based upon a signal sent from a known position and received by the navigator-user. LORAN has been successfully incorporated into tens of millions of receivers afloat and airborne. GPS has an enhanced “fixing” ability, with a smaller location error and better signal safeguards for the user. The Estimated Position and the Dead Reckoning Plot -- other position solutions used by a navigator -- are of lesser value because they are not based upon a signal from a known, stationary position, but rather from a “best guess” of where you are. While EPs and DR plots can be very accurate (especially in the case of a DR plot from an electronic Inertial Navigator (INS), they cannot be considered a fix.
But along came GPS, and the DOD opened it up to civilian/commercial use if at a lesser accuracy than enjoyed by military users.
So, early in 2010, as a “cost-cutting efficiency,” Obama shut-down LORAN. His rationale was that it would save $35 million a year (or, 2/100,000 of one percent of his own budget) and free-up several hundred Coast Guardsmen who had been maintaining the continental LORAN stations employed in generating the signal. The $35M a year, he said, would go to help pay-down the national debt while depriving movers all over the world of the LORAN they had long safely used with gratitude. All the tens of millions of LORAN receivers instant junk.
There were many cries of caution regarding Obama’s plan. One was based upon the fact that GPS is fragile; that its signal is blocked by weather; that there are GPS “holes” where the signal is lost, that the GPS signal is very faint and easily disrupted; that by its nature it has to continuously check itself for update accuracy (a problem LORAN did not share in any large measure). “No problem!” Obama ensured us. Cries that ending all ground-based navigation signals used by aircraft (VORs, NDBs, ILS, etc.) would mean that the country could be left directionless and commercial aviation destroyed if GPS failed or was sabotaged were laughed at.
Well, now the chickens have come home to roost electronically. The EM spectrum is ever more crowded. You see, there are just so many frequencies in the electromagnetic spectrum. It’s not like the Fed, which can just keep printing ever valueless paper money. When the EM spectrum is full, it’s full. Obama can’t print more frequencies. While technology keeps inventing more ways to squeeze the spectrum, there is a finite limit. To the rescue comes the Federal Communications Commission, which is the licensing authority for all radio and TV signals. Hardly unanticipated is the ever greater number of communications providers’ new products. Anyone who has ever used a cell phone or the Internet knows this. Thus, into the fray comes a company called LightSquared. The company is implementing a network of hundreds of thousands of communications transceivers to upgrade its cell phone network and introduce Wireless-by-Satellite service (http://www.washingtonpost.com/business/economy/wireless-by-satellite-startup-hits-fcc-roadblock-over-gps-interference-findings/2011/06/30/AGfe7WsH_story.html). Just one problem: the service will knock-out an estimated 500 million GPS receivers. Most people have experience with this. The top of the FM radio band – 108 MHz – is also the bottom of the aviation navigation band (108 – 118 MHz). Thus you can hear FM music on your analog airplane nav receiver, or navigation signals on your old FM radio (this was inflight entertainment on our nav radio in our Trichamp back in the day).
This situation has created quite a dust-up in communications and navigation circles, as you can imagine. The United States Global Positioning Industry Council is trying to get the FCC to stop LightSquared’s plan. LightSquared is trying to force all GPS makers to upgrade their receivers to be more signal discriminate. The GPS industry says there is no technology to make this happens. The FCC has not made a decision on this case yet, apparently awaiting instructions from The White House.
Meanwhile, spotted around the world, there are now some abandoned Coast Guard stations that once provided a service used and appreciated worldwide. To save $35M a year and make useless hundreds of millions of dollars worth of existing hardware. And soon, perhaps, airliners will use signals from smoke pots and flares as they once did in the 1920s and 1930s. And President Obama has gone golfing again.
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