Adam F Posted February 5, 2005 Report Share Posted February 5, 2005 Q: How should I set me gear up for finding a wreck? I quess that the plotter zoomed in to max and the Sonar to full zoom and max gain? Am I correct and its my numbers letting me down? Adam Quote Link to comment Share on other sites More sharing options...
shytalk Posted February 5, 2005 Report Share Posted February 5, 2005 sounds like dodgey numbers , the plotter is of more use when the wreck has been found if you were looking 8 miles south of needles the wreck s are of reasonable size and if the numbers are close you should trip over it Quote Link to comment Share on other sites More sharing options...
duncan Posted February 5, 2005 Report Share Posted February 5, 2005 possibly the format of the numbers - if they have been passed around it's likely they started life in one format (min/sec v dec.) (even a different datum) and have been re written. doesn't your plotter show a wreck on it's chart? if you wan't to pm me the wreck and numbers I can cross reference it against some data I have for you. if you know which way a wreck is actually facing then it's worth using your plotter to run a grid search across it but if you don't you are as likely to miss it as hit it even on a 100m square (which isn't big enough if the above errors have got in). If it's nice and big like this........ or this then you should of course just trip over it! Quote Link to comment Share on other sites More sharing options...
Manic Moore Posted February 7, 2005 Report Share Posted February 7, 2005 Adam I have a couple of detailed charts that are littered with wrecks but no names. If you pm me your co ordinates from Saturday I will check them on the charts to see if there is anything close. Also I have not seen that wreck name on any of the diving sites? Regards Gordon Quote Link to comment Share on other sites More sharing options...
Swainiac Posted February 8, 2005 Report Share Posted February 8, 2005 Adam, deep in the bowels of my exhaustive reference book library, I have a title, "Shipwrecks of the Wight". This gives accuarate listings of many major wrecks mainly in the west and south wight area, basically penned for divers, but of use to anglers. You may have a lend, I'll dig it out chap. Rich Quote Link to comment Share on other sites More sharing options...
toerag Posted November 10, 2005 Report Share Posted November 10, 2005 I normally have my plotter zoomed in so that I can fit about 4 or 5 track lines on the screen 30m apart. Sounder needs to be on bottom lock and zoomed up to the max as you suggested. To be honest with you, it's almost certainly your numbers putting you in the wrong place. If you have your plotter on WGS84 and you have ED50 numbers then you're probably 200yds out to start with. If I don't know the datum of my numbers then I use the datum convertors on the 'wrecksite' to work out all possibilities and put them in my plotter to start with. Having multiple waypoints makes plodding around much easier to do as you have things to refer to and I tend to search at 3-6knots depending on tide. I don't normally look for wrecks anymore unless I have multiple sets of numbers or genuine confirmed ones. There's too many dodgy decca lists and sinking positions kicking around to make anything else worth searching for. Many wreck symbol positions in the plotter won't be good enough to find the wreck, and if they're marked as PA or PD then you've no hope at all. In reality, I consider anything less then 600 tons to be a small wreck, average is 2-3k tons and big stuff is 6k tons + Think about it, the 'Commodore Clipper' is 13k tons and only 120m long, and there's not many wrecks that big lying around. A small wreck is probably only 6m wide and 60m long. If the wreck is intact, big and lying across the tide then you may get a boil on the surface downtide of the wreck. Most wrecks tend to hold a shoal of mackerel or scad above them too. If it's rough you won't find 'flat' wrecks either, your sounderbeam loses too much power as you roll around, and the swell will make the bottom go up and down. Also, my Koden running at 120Khz is a lot better than my Lowrance running at 200khz. Good luck!! Quote Link to comment Share on other sites More sharing options...
Bob F Posted November 11, 2005 Report Share Posted November 11, 2005 Adam, Like others have said, it's most probably your numbers. If you are sure about the Coordinate system (Degrees, Minutes, decimals or Degrees Minutes seconds) and the Datum (usually WSG84 or OSG36), then you should find the wreck if it's a reasonable size. Your plotter should see it easily enough even if not on zoom. Tip: if the last three digits of either the Lat or Long start with a number greater than 599, the numbers must be decimal, rather than seconds. For example. N 50.29.730 must be a decimal number (you can't go above 60 secs if the numbers were in seconds) Tip: You can use your GPS to do the datum conversion for you. If you are not sure which datum the numbers represent, enter the waypoint twice. First, set your GPS datum to WSG84, enter the number as a waypoint and save as "wrk1-84. Then set your GPS datum to OSG36, enter the same number again, and save as a slightly different name (like wrk1-36). Now you can search for the wreck at both waypoints. It will not matter which datum your GPS is set to when you are searching for the wreck because the GPS will convert your numbers to the datum you are using at that time; the wreck should be at one of the two waypoints. If you find the wreck at wrk1-36 you will know that the numbers you were given were in OSG36 format. Tip: You can do the same for the Coordinate system. If you don't know if the numbers are in decimal or seconds, enter them twice; once with the coordinate system set to decimals (usually denoted as just degrees-minutes), and then set the cooridinate system to degrees-minutes-secs and enter the same number again. So, if I have numbers for a mark and don't know which datum or coordinate system they used, I will enter the same numbers 4 times: 1 - WSG84 Degree-minutes-Decimal 2 - OSG36 Degree-minutes-Decimal 3 - WSG84 Degree-minutes-secs 4 - OSG36 Degree-minutes-secs Remember, most numbers will have been taken prior to EGNOS (WAAS) being available, so they will have a error of 15 meters on average, so you will need to do a bit of searching. It works for me anyway. Quote Link to comment Share on other sites More sharing options...
shytalk Posted November 11, 2005 Report Share Posted November 11, 2005 much easier to start off with the correct numbers!!!!! Quote Link to comment Share on other sites More sharing options...
great white Posted November 12, 2005 Report Share Posted November 12, 2005 Pete I thought you just know where they all are. You are definatly the best person i know at this game, perhaps we need some tips on how to get our memories to work like yours Charlie Quote Link to comment Share on other sites More sharing options...
shytalk Posted November 12, 2005 Report Share Posted November 12, 2005 unfortunately i dont seem to get the chance to often qt needs feeding about Quote Link to comment Share on other sites More sharing options...
Maverick Martin Posted November 12, 2005 Report Share Posted November 12, 2005 Pete You are welcome out on Maverick any time you like so long as you dont mind slumming it on a craft a little smaller than you are used to Martin Quote Link to comment Share on other sites More sharing options...
Bob F Posted November 12, 2005 Report Share Posted November 12, 2005 Pete, Anytime you fancy a bone-shaking, spine-braking ride in a small boat, and launching in freezing cold water upto your wedding tackle, let me know... Bob F Quote Link to comment Share on other sites More sharing options...
toerag Posted November 15, 2005 Report Share Posted November 15, 2005 BobF - your method is completely correct, I just couldn't be arsed to type that all out.... It's also useful to compare your plotter conversion with the one on the wrecksite to see if there's any anomalies. I hate numbers people give you like 49-59-30 1-10-20 - you never know if they should be 49-59-300 1-10-200 or 49-59-030 1-10-020! Quote Link to comment Share on other sites More sharing options...
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