As we proceeded up the Hudson River today, a tow hove into view ahead. Penny, at the helm, noted that he was upbound, too. After a few minutes, I looked up and observed that the tug was not only closer but behind the barge; he was in fact, downbound. A glance at the AIS display (on CE) showed the triangle symbol facing the wrong way! Further investigation showed that all the data was correct, including course, but his heading was fixed at 17 degrees! So we learned something today, fortunately not the hard way: a simple glance at that elongated triangle may not always tell the truth! Regards, John "Seahorse" ************************************** See what's free at http://www.aol.com.

I'm used to seeing a projected course track that extends outward from the target, the distance proportional to the ship's speed. At least that's how Furuno displays show it when using the Furuno AIS. Very handy, as you can graphically see where the target is going to cross your course line. Not sure if all units work that way or if that would also have been confused by the tug. John Marshall N5520-Serendipity On Jun 3, 2007, at 5:39 PM, Truelove39@aol.com wrote: > As we proceeded up the Hudson River today, a tow hove into view > ahead. > Penny, at the helm, noted that he was upbound, too. After a few > minutes, I looked > up and observed that the tug was not only closer but behind the > barge; he was > in fact, downbound. A glance at the AIS display (on CE) showed the > triangle > symbol facing the wrong way! Further investigation showed that all > the data > was correct, including course, but his heading was fixed at 17 > degrees! So we > learned something today, fortunately not the hard way: a simple > glance at > that elongated triangle may not always tell the truth! > > Regards, > > John > "Seahorse" > > > > ************************************** See what's free at http:// > www.aol.com. > _______________________________________________ > http://lists.samurai.com/mailman/listinfo/passagemaking-under-power > > To unsubscribe send email to > passagemaking-under-power-request@lists.samurai.com with the word > UNSUBSCRIBE and nothing else in the subject or body of the message. > > Passagemaking Under Power and PUP are trademarks of Water World > Productions, formerly known as Trawler World Productions.