Whether you use vector or raster charts you still have the burden of keeping them updated, just like your paper charts. You do keep them updated to the latest USCG Notices to Mariners, don't you?
The Local Notices to Mariners bulletin is available as a free weekly mailing from the Coast Guard. Call them to get your name on their mailing list. This method is the slowest. Because of production and mailing delays, these update notices will actually be several weeks the times. There are several faster ways to get the latest updates. You can use an electronic bulletin board service or take a look at www.navcen.uscg.mil and download the latest updates to your printer.
The simplest, least expensive, but the most laborious way, is to hand enter the updates from the Notices to Mariners into the computer. For this reason be sure that the navigation software you select is annotation-capable, as well as user friendly. Each program handles this option in different ways, so be sure to check this out before you buy.
Some GPS plotters may not offer this capability.The fastest, easiest, but more expensive, way to keep your charts current is to subscribe to your vendor's chart-update service. Resolution Mapping offers a monthly service that provides a correction overlay. Transas provides an on-demand or quarterly update on CD-ROM or floppy disks and via the Internet.(See sidebar Electronic Charting Terminology.) Others like BSB/NDI and ARCS offer updated CD-ROMs that provide you with the latest version of the charts. The new ENC vector charts by NOAA, and distributed by Maptech under a CRADA, will come with free weekly chart updates.
You should be aware, however, that any chart updates received via CD-ROM or floppy disks will contain the latest version of the chart and changes up to the time of production. They will not include the Notices to Mariners changes that occurred between production and shipment. These changes must be manually updated to make the charts current.
The IHO has decreed that no ECDIS or ECS navigation program may be used in lieu of paper charts. To be perfectly legal, mariners must have paper charts and the latest Notices to Mariners on board. The changes need not be posted to the charts, but you must show the capability to do so if the need should arise. They have also recently finalized the specifications of the electronic chart standard. The new standard, S57 ed.3, requires vector-ized charts on all electronic charting systems used on board commercial vessels. Recreational boaters can use the more basic functionality of an ECS navigation program with ARCS, BSB/NDI, ENC or Maptech raster charts, but also must have paper charts and updates immediately available.
Next fall Maptech will distribute new CDs for U.S. waters. These CDs will contain the new NOAA ENCs for the 80 deep-water ports and raster charts for the surrounding areas. The price will include free weekly chart updates for one year. NOAA and the USCG want you to have the capability of downloading the latest updates and corrections via a commercially provided Internet site. They feel that this will be the best and perhaps the only way to ensure that all mariners can comply with the IHO standards and have immediate access to the most current data.