Professional Mariner #66 – Aug/Sep 2002

Imagine being able to know the name, speed, destination and even the cargo of an approaching ship simply by looking at an electronic display in your wheelhouse. Soon, you won’t have to imagine; the concept will shortly become reality with AIS — automatic identification system — a new technology designed to improve maritime safety, security and vessel traffic management.

AIS employs a shipboard transponder system that continually transmits data on a common VHF radio channel to other nearby ships and people onshore who are monitoring the information. An AIS display will look like a radar display with overlaid electronic chart data that shows not only where ships are — but also the names of those ships, their course and speed, their destination, and what cargo they are carrying.

The safety benefits of AIS are obvious enough. Today’s generation of navigation electronics doesn’t allow mariners to identify any given radar target, particularly when multiple contacts are being tracked. This problem becomes a particular concern at night and in bad weather. AIS, however, provides a standard system by which ships can readily receive a bounty of information.

AIS isn’t just about being on the receiving end of the data, though. It also allows ships to transmit information automatically, rather than having ship personnel be distracted from more pressing tasks when navigating in congested waters, tricky currents or adverse weather conditions.

This image shows the AIS display aboard a ship making a turn at the Hillsborough D Cut in Tampa Bay. The box on the uppper right provides information about the ship, including its position in the channel, distance to the beginning of the turn, heading and speed.

Since the terrorist attacks of Sept. 11, the security benefits of AIS have become more apparent. AIS gives the U.S. Coast Guard, other agencies and seafarers a new mechanism to track vessels and spot suspicious behavior.

The International Maritime Organization’s regulations will require that nearly all large ships be outfitted with AIS equipment. The regulations will be phased in over the next five years, depending on the types and sizes of the ships. In addition, the United States is expected to apply the regulations to ships that ply inland waters that are not covered by the IMO.

Beginning July 1 this year, all newly built ships must be fitted with AIS equipment. In time, AIS units will be required on all ships at least 300 grt that are engaged in international voyages, all cargo ships 500 grt and larger not engaged in international voyages, and all passenger ships, regardless of size.

Stuart Tolman, U.S. sales manager for Leica Geosystems Inc., said his company recently received an order for 14 AIS units for Holland America cruise ships. The cost for AIS equipment ranges from under $10,000 to about $15,000 for full-blown, top-of-the-line units.

“This is another navigation tool,” Tolman said. “And the more tools you have and use correctly, the safer the oceans will be.”

Capt. Larry Simpson, a field application engineer with Ross Engineering Co. in Largo, Fla., said AIS represents a leap forward for ocean navigation. AIS will give mariners information at their fingertips they previously could only dream of having.

“It’s going to be huge,” Simpson said. “With AIS, you know who’s all around you.”

This AIS display depicts a ship in the middle of a turn in a channel in Tampa Bay. The box at the lower right displays information about another vessel in the area selected by the pilot of the ship. In this case, the pilot wanted data on Egmont, the pilot boat he planned to meet at the sea buoy.

Aircraft have been required for years to carry AIS-like transponders that give real-time information about identity, direction, speed and the like to people on the ground.

One of the obvious benefits of AIS is that it provides an improvement over radar. It extends a radar’s range, it works better in bad weather, and it can identify ships that are out of sight — such as around bends in rivers or on the other side of islands.

Pilots in Tampa Bay, Fla., have been using basic AIS devices for about five years when piloting tankers, cargo ships and other vessels into the bay.

Kathy Dalpiaz, operations manager of the Tampa Bay Pilots Association, said some pilots were leery of the devices at first. Now they swear by them, especially in the thunderstorms that plague that area of Florida.

“You hear them say, ‘Thank God I had it, because I couldn’t see a thing,'” Dalpiaz said.

Besides providing a step up from radar, AIS also supplies information that was previously unavailable electronically.




According to the Coast Guard, a Class A AIS unit will broadcast a ship’s navigational status, speed (to within 0.1 knots), course, heading, position and identification number every two to 10 seconds while underway and every three minutes while at anchor.

In addition, every six minutes, an AIS unit will broadcast information that includes a ship’s radio call sign, its dimensions to the nearest meter, the cargo it is carrying, its draft, its destination and its estimated time of arrival.

Tolman said that type of information is invaluable anywhere, but particularly in high-traffic areas such as the English Channel, New York and Los Angeles.

Not surprisingly, much of the talk about AIS these days turns to security, since the terrorist attacks of Sept. 11 are still fresh in everyone’s minds.

AIS will allow the Coast Guard to keep track of vessels — and perhaps more importantly, spot suspicious or out-of-the-ordinary behavior. If the vessel turns off its AIS, the Coast Guard and others would be aware of that and could act accordingly.

Matthew Wood, assistant national sales manager with Furuno USA, said some shippers would like to see future AIS models be equipped with a silent alarm, the type that banks have to notify police when a robbery is in progress. That way, mariners could transmit distress signals silently if terrorists or pirates were overtaking them.

There is the added question of whether AIS could become a tool for terrorists to track and monitor ship traffic — just like mariners and the Coast Guard.

“The downside is that because it is automated and anyone can buy one, it is in the public domain,” Wood said.

Already, though, mariners who have been testing AIS units say it makes them feel safer and more secure. Capt. Douglas Grubbs, of the Crescent River Port Pilots Association, told a congressional subcommittee earlier this year that an AIS-based vessel traffic management system is under development in New Orleans.

The Lower Mississippi River is one of the largest port complexes in the world, with hundreds of thousands of vessel movements each year along the stretch from Baton Rouge, La., to the Gulf of Mexico. Grubbs told committee members that mariners on that stretch have been on heightened alert since Sept. 11 and that AIS gives them the information they need to act appropriately.

“We cannot afford to drift again into vulnerable complacency,” Grubbs testified. “This means that emergency measures must become standard operating procedure, that complete, accurate, real-time situational information must be readily available to both operators and law enforcement personnel, and that maritime personnel learn how to identify and respond to potential threats quickly and efficiently.”

For now, a German governmental agency has been testing different AIS units to make sure they can communicate with each other and operate as designed. A Leica model was the first to be officially approved.

The IMO is also considering an accelerated implementation schedule for AIS on existing cargo ships. And some people are suggesting that AIS units be required on smaller boats, such as recreational sailboats and fishing vessels that now don’t fall under the AIS regulatory regime.

Jorge Arroyo, U.S. Coast Guard regulatory project officer for AIS, said the Coast Guard is developing its own regulations beyond those required by the IMO. The rules, which should be published shortly, will specify which vessels not addressed by the IMO rules will have to carry AIS in U.S. waters.

The Coast Guard is already using vessel traffic management systems with AIS in New Orleans, Berwick Bay, La., Prince William Sound in Alaska, and Sault Sainte Marie, Mich.

In the meantime, the day is near when AIS will become mandatory equipment on ships. And everybody agrees that is a good thing.

“It is a significant development that represents a blend of technologies that hadn’t been applied to the marine market before,” Wood said.

By Professional Mariner Staff