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How dare they threaten sailors’ navigation nirvana?

2021 April 1

Here’s a tip for productive use of that surplus time made available by pandemic protocols: Dive into your repository of disused sailing clutter and excavate your old loran receiver. You might need it.

I am referring to that boxlike object with knobs, buttons and a small screen for displaying numbers that was rendered an antique curiosity by the miracle of GPS.

This may be news to Gen Z, but there was a time in human history when GPS did not exist.

You can’t blame people born after 1990 (sometimes called Zoomers) for being unaware of this because they’ve only lived in a time when GPS is so ubiquitous it seems civilization would descend into chaos without it. Actually, it might.

These days, navigation is just a side benefit of GPS. Power grids, financial markets, transportation systems, millions of smart phones all over the world and such crucial contributors to the consumer culture as Amazon cannot function without data extrapolated from GPS satellite signals. 

When this wonder first appeared, it was seen as an aid to navigation. That was a naive underappreciation of the invention. GPS was not an aid to navigation, it was all you needed for navigation. It turned everyone with the wherewithal to buy one of the ever more affordable devices into a navigator capable of the most precise position-finding man has ever known.

Some sailors wept for joy. Others were skeptical. It’s too good to be true, doubters warned as they polished their sextants. Keep practicing your navigating skills, they counseled, stay sharp at dead reckoning, master celestial navigation, keep your loran plugged in, don’t deposit your radio direction finder where it belongs (in the trash).

I couldn’t resist commenting on this at the time in an F&B column, poking good-natured fun at the Chicken Littles who worried the sky could really fall and bring the satellites down with it, victims of collision with asteroids or space debris, assault by solar flares or zapping by evildoers.

I didn’t have to eat those words. GPS has been our reliable friend for more than 25 years, improving as it has aged. It was amazing at first when it was accurate to 100 meters (even during the time when the U.S. government applied an intentional error for military security reasons), and now it’s more amazing, telling us where we are almost any place on earth within 16 feet.          

For good measure, the signals beamed from atomic clocks aboard GPS satellites are so precise they are used to control financial transactions, transmission of cellular tower data and power grids. 

And yet, the worriers are back, and this time they are worth listening to.

Hackers are targeting GPS; apparently that’s not hard to do. Signals from GPS satellites are weak because they have to travel so far from space, which makes them vulnerable to being jammed or overridden by fake signals, a criminal act called spoofing. This sort of mischief has accelerated, with numerous attempts at interference documented in just the last few years. Ships have reported GPS positions that placed them more than 100 miles inland in Russia when they were well offshore on the Black Sea. Russia and China have been blamed for intentional disruption of GPS.

These big bad actors are just part of the problem. GPS signals are such easy targets that it doesn’t take a sophisticated attack by a superpower to corrupt them. I’ve heard that teenagers use GPS jamming devices to defeat tracking apps used by their parents. You can buy something called an “anti-spy GPS jammer” to block “the ubiquitous messy signals in life” from Amazon for less than $100. (Your order will no doubt be tracked by GPS.) These do-it-yourself disruptions can affect other GPS receivers some distance from the source of the jamming.

The U.S. government owns the GPS system used in this part of the world and the Department of Defense spends close to $2 billion a year to manage and maintain it. I’m not complaining about any of my tax money spent for this. GPS is worth it. Besides, we get to use it free of charge. But I am complaining about another government agency that may be complicit in degrading the reliability of GPS.

In April 2020, the Federal Communications Commission announced it would approve a license for a 5G data network to be operated in the same space used by a key satellite navigation spectrum. The 5G signals can interfere with GPS signals.

This is bad news for us boat people, but at least it can be said that we have strong allies in trying to stop this misguided move to give faster cell phone service priority over an essential navigation system. Opposition to the FCC decision has been registered by the Defense and Homeland Security departments, aviation interests, scientists, advocates for first responders and, fittingly, BoatU.S.

If this sounds familiar, it is because something like it happened in 2012 when a company called Lightsquare almost got approval for a land-based broadband network with radio signals that intrude on the GPS spectrum and could have overwhelmed GPS receivers. Then, the FCC listened to scientists and others defending GPS, and denied the license. That sent Lightsquare into bankruptcy, but now it’s back with a new name, Ligado, and this time it has the
FCC’s support. 

With that joining the other enemies creeping up on GPS, it is obvious that a backup is needed, which brings us back to loran. 

A new version called eLoran is being developed with the promise that, for vessels within its range it will be almost as accurate as GPS, perhaps to within 100 meters. It uses high-powered radio signals for time difference calculations (remember those TDs from the early days of loran?) for navigation. When it’s set up to cover most U.S. waters, it is expected there will be 19 transmitting towers operated by the Coast Guard.

“It’s not your grandfather’s Loran-C,” said the president of Hellen Systems, a Virginia company that  develops and deploys eLoran systems. He explained it uses the same frequencies as old-school loran, but differs in that it has solid-state transmitters and digital signals.

I’m guessing that means our old loran receivers are not going to work. That’s a pity, but let’s just hope that the newfangled loran works as promised. Otherwise, who knows, the next backup in line could be, perish the thought, radio direction finding.

I checked, and a few RDF beacons are still around. Doubtless, more could be added if we had to return to the cave-man era of electronic navigation. I have a vivid, if not haunting, memory of having to haul the big RDF box up to the cabin top in a gale (because the signals could not penetrate below), and amid the crazy motion and dollops of spray, turning the antenna in search of signals and trying to recognize the codes in the faint beeping. We eventually triangulated a position somewhere in a city-sized expanse of water.

Of course, I’m spoiled by GPS. Aren’t we all?