Print On Demand Navigational Charts Coast Pilot® Electronic Navigational Chart Dates of Latest Edition Raster Nautical Charts

(Reformatted from June 1998 "Workboat Magazine")

The National Oceanic and Atmospheric Administration has launched a number of ambitious programs designed to update its suites of paper and electronic charts and get them into mariners' hands quickly.

These initiatives are now being tested, and mariners will likely see the products available for sale by the end of the year, according to officials at the Office of Coast Survey, a division of NOAA's National Ocean Service.

RASTER, VECTOR UPDATES
NOAA has been gradually changing the way it makes charts. Until four years ago, cartographers would use a manual drafting and engraving process to produce charts. It took almost eight months to revise and print a chart for public use. Today, thanks to advanced computer technology and digital files, NOAA has cut the lag time to about two months.

And, an even short turnaround is planned. Soon it could take just a few days for electronic updates.

In 1995, the agency introduced raster nautical charts, which are georeferenced electronic images of paper nautical charts. These are exact reproductions of the paper charts familiar to mariners, except that they appear on the user's computer screen. (All 1,000 NOAA paper charts are available as digital raster charts). The raster charts have been wildly popular since their introduction, with 1.2 million of them sold in just three years.

To further improve the accuracy and timeliness of the charts, NOAA is developing a weekly update service. The agency has already entered into a partnership with MapTech Inc., Greenland, N.H., which will provide the updates.

Here's how the service will work: NOAA will receive, in advance of public release, all navigation-related corrections from the Coast Guard, National Imagery and Mapping Agency and the Canadian Hydrographic Service. Updated files will be sent to MapTech via a high-speed data line. The company will create an "electronic patch" for the mariner's CD-ROM collection of raster charts.

Patches will be available to paid subscribers via the Internet and on floppy disk, as well as through marine speciality stores and chart agents. The coast hasn't been set yet.

'Electronic patches' containing chart upgrades will be available via the internet.

When a patch is applied, revisions will appear on the user's computer screen, but he can still return to the old chart. The new information will include such things as the repositioning of buoys, the removal of obstructions and alteration of navigation channels due to dredging.

Very little is required of a mariner to use raster charts. He needs a computer--any kind of PC or portable will do--navigation software, which costs around $500, and the data charts, priced at about $200.

The update service will be tested in June, with the goal of bringing it totally online by the end of the year.

The entire system can be up and running for less than $3,000 according to David Enabnit, technical director of the Office of Coast Survey. "You could go to any computer store and get your computer, and your high school son could set the program up." he said.

"The real advantage is real-time positioning," Enabnit added. "There are also voyage-planning features and offtrack alarms."

Rasters are currently used by the Navy, Coast Guard, NOAA and on many boats in the workboat industry. However, although easy to use and highly accurate, they aren't recognized yet by the Coast Guard as a primary tool for navigation. Coast Guard regulations require that up-to-date paper charts be aboard a vessel as a backup.

NOAA is also moving ahead with developing digital, electronic vector charts. Unlike rasters, which provide an exact picture of the area being navigated, each vector chart is backed up by a database that will provide additional information and offer better links with radars and other shipboard systems. The digitalization of data will also make vectors more accurate than rasters, NOAA said.

Vectors intended for deep-draft, commercial vessels will allow a ship's navigation system to provide warnings and information that is based on the ship's particular characteristics. For example, depending on the vessel's draft, the system will indicate areas that would be dangerous to transit.

Because of cost considerations, NOAA is initially concentrating on the nation's 100 most-heavily trafficked ports. These vector charts will be available early next year for a yet-to-be determined price.

Plans are also under way to put the inland river system on vector charts. Data will be taken from the U.S. Army corps of Engineers and other sources.

"There's a big need for charts that are kept up to date, because there's a large amount of changes on (the Mississippi River) and a big amount of traffic," said the chief of the Corps Marine Chart Division, Capt. David B. MacFarland.

Navigation on the rivers is now done mostly with outdated paper charts prepared by the Corps. "The vector chart will give mariners on the rivers access to piloting and navigation information they didn't have in the past," MacFarland said.

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