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Two things to toss in the pot; Firstly, how we grapple (wrecks down to 70m, though I don't dive that deep - yet). Find the wreck on GPS, or whatever. Drop a reference shot. This should be a very heavy weight, with a small, highly visible buoy; on the mimnum line to prevent windage or current drift. Then use this a visual clue to square spiral or circular search, or parrallel lines if you know the orientation of a long wreck. This gives you a visual clue to grapple by. Us an excess of line and low speeds. This has been the cause of some polite discussions; I favour the routine described below, others believe that line=depth and speed <10kts will work. Hey ho. Secondly, a GPS offshore engineer described the routine when laying transatlantic cable and the cable snapped; down whips the end through a kilometre of water. The end could be absolutely anywhere. They back up six km, and head to one side of the cable track by 1 km. Ove the side goes a *three km* grapple line, and the ship moves across the track of the cable at 90 degrees at one quarter of a knot true motion. Works every time. I recommend then, using double the depth of line, and less than one knot speed. Rocky bottoms do cause problems, but off-shore there aren't too many of them. When you hook, you know it. Tying the hook on *is* a good idea, especially if you intend to tie the boat off; I feel better with a live boat on the surface, myself. BTW in heavy swell, like a couple of meters, use extra line. Think *big* think *slow*. McJason.
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