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Thread: Follow the ARC
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post #36 of Old 12-04-2012
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Re: Follow the ARC

Originally Posted by billyruffn View Post

LP said they got a reaction from LA with the light but LA took no action. It could have been that LA was getting ready to take action, like I mentioned above, but was waiting until they got within a few hundred yards to see which way the crossing was going to happen. LP had no way of knowing whether this was happening or if LA was tracking them on radar, as they got no reply on VHF. I think that's were LA messed up -- how hard is it to get on the radio to call the boat that's "at Lat X, Long Y and just flashed a light at me"?
Yeah, that's the inexplicable part of this encounter, to me...

Well, at least they were showing their tricolor light... These kind of encounters seem to happen every year in the ARC, but I remember a few years ago one boat being similarly "stalked" by another that was running dark, showing no lights whatsoever... Perhaps after shooting their wad on the entry fee, they had nothing left over for those pricier LEDs, huh? (grin)

Originally Posted by billyruffn View Post
It's also hard at night to judge a constant bearing. I've noticed during the day that what seems like a constant bearing on a boat 1-2 miles away becomes a rapidly changing bearing once they're inside a 1/4 mile. In a big sea like that LA and LP were in, it's particularly hard to judge a constant bearing because the boat's moving around so much.
You've certainly got that right... Mark has asserted that this close encounter "clearly" would have been averted had only both boats been equipped AIS and transponders, and mocks us wankers who might still rely on such a hopelessly outdated tool as a hand-bearing compass in such a situation...

However, with the sea state and conditions as described, and the courses being steered by both at the time fluctuating constantly and markedly, the utility of a technology as accurate and precise as AIS will be greatly diminished... The information displayed will be fluctuating wildly, between showing a collision course, and a safe crossing, or no crossing at all... And, of course, the effort to interpret the information displayed, and "average it out" in order to determine the proper course of action, will necessarily involve an inordinate amount of time staring at an AIS display screen, rather than across the water, as the situation is developing...

In this particular situation, I think a well-dampened hand bearing compass - used in conjunction with a pair of trusty old Mark I eyeballs, by a wanker who fully appreciates the danger of a "Constant Bearing, Decreasing Range" target at sea, at night - might have still have been the most useful tool for either crew to have had at their disposal...

Last edited by JonEisberg; 12-04-2012 at 08:11 AM.
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