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    Re: Lights etc.
    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{at}MATH.UU.NL]
    Sent: Tuesday, October 14, 2003 01:53
    Subject: Re: Lights etc.
    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?
    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.

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