The marriage of the PC, GPS, and electronic charts is a double-edged sword. The system, when it is operational, definitely reduces workload for a short-handed boat, and helps with navigation in tight spots.

But the system is not foolproof. One must use the same care with these systems as with conventionally plotted positions.

There are two major risks that we’ve seen. First, many charted objects are out of position. In the Caribbean Islands, for example, it was not unusual to find Beowulf anchored on land according to the charts. The fact that you are off by an eighth or quarter of a mile (sometimes more!) is not a problem as long as you don’t depend on the charting system for pin-point accuracy. The old adage about never trusting any single source of nav data still applies – always confirm your charted position with the radar, a visual bearing or the depth sounder.

The second problem is inopportune “crashes” of the charting system and/or computer.

We’ve been using Nobeltec Visual Series. In the main, it has proven reasonably reliable and easy to use. However, it does crash occasionally for unexplained reasons. The most recent example was working our way into Newport, Rhode Island at night. Just two miles from the harbor entrance the Nobeltec program locked up. Of course we had our paper charts right there, and were taking radar bearing at the time. Still, it was a bit disconcerting to think we might have been trying to trace our way back out of a difficult anchorage in an emergency – where this could have cost us the boat!

While we will be looking for a more stable program or perhaps an upgrade of the Nobeltec software, we are definitely hooked on the concept and use of electronic charting.

This article elicited responses from some of our readers, which we’ve posted here:

I have had a “lock-up” experience with the Nobletec Navigation Suite just recently approaching an anchorage. it was no big deal since we had good visibility. However, terminating the application by simultaneously pressing CTRL, ALT and DELETE and Restarting the computer and the software isn’t that big a deal either.

– Peter H. Eberle, UHURU II, Grand Cayman (added 06 October 00)

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Re: your comments on electronic charts – We use Nobletech Visual Navigator and occasionally have the same lock-up problems. Interestingly we have also found that the removal by the US Govt of the deliberate error does not seem to have made ours more accurate. We use Maptech raster charts.While on that, we are looking for second hand Maptech raster CD charts for New Zealand – anyone upgraded to vector charts and want to sell their raster charts?

– Mike Scott (added 21 July 00)

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I just wanted to drop you a note on your “chart software lockup.” I grew up on a boat and have sailed extensively. I have a Masters in Computer Science and make my living developing software. Microsoft Windows (NT, 95, 98, 2000) all use libraries called DLL’s. A single program might interact with 50, 100 DLL’s. When the program gets installed it looks at the DLL’s on your system and copies in any versions that it shipped with that are newer or that you do not have. There is no guarantee that newer is better or that it is even accurate. The software uses the “date” on the file to determine newer but this date can be changed accidentally. When you install a second program it will do the same with the DLL’s. No guarantee that the first and second program will even work with each other’s DLL’s. They are likely to share some DLL’s.

The net result is what we in the software industry call “DLL Rot”. Software quits working for inexplicable reasons and programs, which used to work, crash. An example of DLL Rot is the computer that I am sending this e-mail to you on. For some reason Microsoft’s installer program no longer works on this computer. I can’t install Office 2000. This is only a minor irritant to me because I have 9 computers in my office that I use.

If I were to use a “charting” program I would install it onto a computer preferably running Windows NT or 2000 and then NEVER EVER EVER install another program on that computer.

Maybe this will help you or somebody else that you pass the information on to.

– Philip (added 21 July 00)