NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lights etc.
From: Doug Royer
Date: 2003 Oct 14, 12:04 -0700
From: Doug Royer
Date: 2003 Oct 14, 12:04 -0700
Steven,I'm not sure how to interprate what you stated as to my tolerance of what my nerves can stand.Do you think I'm being overly defensive taking such a stance?It's like a game of chess at best and a game of billiards at worst out there.I'm not the one who will most likely be hurt in a collision with a small vessel but the paperwork generated and time lost by a collision are substantial.I don't mean to come off as flippant about this because of the seriosness of the subject. Do you know anything about ARPA radar?When I'm on vessels that have ARPA my job is basically done.All the OOD or ABS has to do is place the curser over the target and click on it.The true course and speed,CPA+time of CPA,Lat. and Lon.,projected positions and new CPAs into the future are shown relative to my vessels same positions instantaniously.Multiple targets are chosen and tracked.What a tool! On vessels that dont have it the old relative motion plots or boards are used and are more time consuming but just as accurate.It only takes at max. 6 min of time to find all the above info per vessel the old way.These are the ways I will know if one is anchored or not and fairly quickly.When visual contact is made the running lights are used to determine instantanious changes in the targets aspect and may give forwarning of the need to start plotting new relative motion info or watching ARPA.So,useing relative motion plots I already know you are anchored or drifting.When visual contact is made I can,by the running lights or absence of them,have an idea of what you're up to and plan accordingly.Here's an example of what I mean by I prefer the white all around mast light.I accure you at 27 nm on radar.At max. in 6 min.I know the above info but cannot see you visually yet.Because the white mast light is high above your vessel that is the 1st thing I'll accure visually way before I see any of your running lights.One can't always see those tricolor mast lights at distance clearly enough to discern the vessels aspect.I would rather see the all around green + red mast lights etc. instead of the tricolor. Now that said,I use at min. 10x binos.Even on large vessels one can't always hold them steady enough to get good visuals at distance.A few years ago I got a pair of motion stabilised binos in 10x and with some lens coating that makes even darkness a little brighter.These are the best thing since sliced bread!What a differance in the ability to see things at distance useing these over other binos.Also,I've found that useing any set of binos with the eye cups or blinders attached helps in seeing things at distance better. To tell you what I found last night reguarding the all around lights.I went to the commercial docks to see the nav. light configurations of these vessels.These vessels are all over 7 m (most are 65-100 ft. in lenght.All have regulation lights and all have all around mast lights at the top of their masts.I asked a few of the guys and they stated that yes,in these waters,they have them on while underway because other vessels see them before any other lights because they are at the highest point on the vessel and can be seen at a further distance.It gives another boat a visual clue something is out there sooner than not useing them.Most small boats here don't have radar or very good ones if they do I'm told.Apparently the C.G. looks the other way for safety reasons on this practice here for now. -----Original Message----- From: Steven Wepster [mailto:wepster@MATH.UU.NL] Sent: Tuesday, October 14, 2003 01:53 To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM Subject: Re: Lights etc. Doug, I feel strengthened now in my choice of navigation lights. Thank you for that. I'd like to ask two more questions to you. If you were in shallow waters, would you be confused by my white light and think that I am anchored? Or is radar giving enough evidence that I am not, even when my speed is only about a knot (in which case the whole question is beginning to loose its significance)? Second question: do you ever get confused by the sector boundaries of the tricolor light on a jawing yacht? Jared, I have no idea how cp translates into power needs. I want to remind you that a sailing vessel, when under way, will have side- and stern lights on, besides the optional red-over-green. That will add an extra 12.9 cp, spoiling the benefit. In my country we have a choice of 10W or 25W bulbs and I use the latter. I believe that the bulbs and housings are designed to meet the regulations. Steven.