Virtual Navigation Is Here, Like It Or Not

Even though contemplating it can come across like the old "if a tree falls in the woods" brainteaser, the age of "virtual navigation" is here, and it's very real, indeed. Even as you read this, navigation aids that exist only electronically, and only with the sophisticated gear to "see" them, are guiding oceangoing vessels in and out of San Francisco Bay, and around parts of that busy harbor, day and night, in good weather and bad.

On March 12, 2014, the U.S. Coast Guard began operating 25 fully functioning "virtual" and "synthetic" electronic aids to navigation, or eATON, as the agency labels them, in San Francisco waters. It's their latest advance in a nationwide system based on rapidly evolving Automated Identification System (AIS) technology. The goal is to make waterways safer, and to help the agency's mission and operations become more efficient.

AIS is a VHF radio broadcast technology that allows vessels to identify each other while underway and continuously share vital information such as course, speed, and destination, all in the interest of safe navigation. International maritime agreements have required AIS equipment on large commercial vessels (more than 300 gross tons) since 2004, and such transmitters and receivers, while not required, are increasingly found on smaller vessels, including a growing number of recreational boats.

The Coast Guard, which operates AIS shore stations, now uses the technology to identify its aids to navigation and to signal the characteristics and coordinates of each to electronic charts and other navigation displays, and even via properly integrated personal computers, tablets, and cell phones. The broadcast system is now fully operational throughout the U.S., except in the Great Lakes. In addition to standard AIS capabilities, the technology includes three types of electronic aids classified as Synthetic, Real, and Virtual — and each has different uses and applications.

Three Tools For Today's Future

Synthetic eATON refers to a physical buoy, fixed marker, or other conventional aid to navigation that transmits its exact position to a shore station every three minutes. The shore station, in turn, broadcasts an AIS signal with the buoy's 9-digit Maritime Mobile Service Identity (MMSI) number, similar to the one in your boat's VHF radio that looks as if it is coming from the buoy. From your helm, you would see a real buoy bobbing in the waves, and you'd see the same buoy on the chartplotter even though the buoy itself is not equipped with AIS.

While not yet functioning within the system, the Real — also called Physical — AIS eATON would be an actual buoy or other conventional aid that is equipped to broadcast signals of its own. For example, installed aboard a lighted buoy would be a GPS chip and an AIS transmitter with its own power supply. The Coast Guard will be testing that technology over the next year to determine its best use as part of the overall U.S. navigation system. But when it comes to the Virtual AIS eATON, well, what you don't see is what you get.

"For the Virtual type, we're broadcasting a signal from a base station [or another ATON] to, for lack of a better term, a hole in the ocean," reports Commander John Stone of the Aids to Navigation Branch in the Office of Navigation Systems at Coast Guard headquarters. "It would be a spot where there's no physical aid to navigation. You could only see it if you had an AIS receiver or an integrated radar."

The advantage of the virtual aid in the maritime here and now, Stone explains, is that it allows the Coast Guard to deploy navigation markers on a temporary basis, or in an emergency, like marking a temporary hazard or sunken vessel. In fact, during the 2013 America's Cup race, the Coast Guard marked security zones with virtual buoys to control the spectator fleet in San Francisco harbor. Last winter, when unusually heavy ice in the Chesapeake Bay's Pocomoke River dragged 16 buoys off station, the Coast Guard remotely deployed virtual aids to mark the shipping channel.

As a practical matter for recreational boats equipped with AIS, Stone notes that virtual aids, like the ones marking the ship-traffic lanes in the San Francisco ocean approaches, can help small craft stay out of trouble, too. In fact, he relates the case of one local boater who lost his bearings offshore in fog last year but, with AIS, found the "SF" buoy, now equipped as a Synthetic eATON, marking the ship-traffic lanes. That enabled him to "work his way home and still avoid commercial traffic," Stone reports.

But while more and more recreational boaters may be adopting and adapting to AIS equipment, the vast majority still don't use it and may never find that level of electronic sophistication practical, or even necessary. BoatUS reminded the Coast Guard of these facts as the agency began discussing its plans for an eATON system nearly 18 months ago. In testimony to the U.S. House of Representatives subcommittee on Coast Guard and Maritime Transportation, BoatUS president Margaret Podlich said, "Unlike commercial vessels, recreational boats are much less likely to have sophisticated electronics needed to access some of the newer proposed systems, such as virtual buoys projected on electronic charts. There's still a significant need for the tried-and-true physical ATONs in areas where boaters operate, such as shallow-draft harbors and channels. Although we understand the need for budget restrictions," she continued, "we emphasize that the removal of many of these ATONs could lead to higher numbers of boaters in distress, loss of property, and a greater number of search-and-rescue operations."

For the Coast Guard's part, Stone says his agency recognizes these important considerations: "To date, we have not replaced any physical aid to navigation with a virtual aid. A key goal right now is seeking stakeholder input on how to best use this technology within our ATON constellation." In fact, last year the agency, along with NOAA and the Army Corps of Engineers, held 12 "listening sessions" around the country intended to bring the maritime community at large up to speed with the emerging world of eATON, as well as a host of technological advances in "e-NAV" and navigation-information delivery. The two-hour sessions, Stone recalls, proved as instructive for the Coast Guard as for the maritime community in each port.

"We found out very quickly that we weren't capturing the viewpoints of recreational boaters at these meetings," Stone says. "The majority of attendees came from the commercial maritime community, which was critically important, but that left out a huge segment of waterway users from whom we needed input." To fix that, and to continue gathering opinion, perspective, and experience from people who are out on the water regularly, Stone's office developed an online survey that any boater can access. He says the survey is "specifically focused to grab the recreational boaters' opinions" on the future of navigation. In fact, the sailing-in-the-fog-off-San Francisco anecdote came to Stone's attention via the comments section in the online survey.

Will Virtual eATON Bump Your Buoys?

One question on the feedback survey asks respondents to pick their "biggest concern" from a list of six potentially negative future scenarios. One choice — and it's been on the minds of some in-the-know boaters already — is "reduction in aids to navigation." In other words, if these virtual aids prove to work exceptionally well, would the Coast Guard start replacing buoys, daymarks, and other physical aids with the electronic-only variety? Stone says no, but with careful qualification.

"Can I say we're going to take our 48,000 aids to navigation and cut back to — oh, pick a number — at some point in the future?" he says. "No. But if we determine that the best aid to navigation at a particular location is a virtual aid, then, yes, we'd consider replacing it, because we're constantly looking for the best ways to provide service to the mariner. I wouldn't look at that as a reduction in aids to navigation, but as improvements to the system. And we wouldn't be going down that road without close input from all our stakeholders."