NAUI Master Scuba Diver 260 Boating, Diving, and Seamanship Weight must be carefully arranged in these boats to keep the bow down, especially in high wind. Any metal boat also requires measures protecting against electrolysis. The most popular sizes for open skiffs range from 5.5 to 7 m (16 to 21 ft), although both smaller and larger ones are available. There is generally more room than in an inflatable, but they also ride wetter, so it is best to suit up before leaving the dock. Diving procedures are almost identical to inflatables, but in some larger skiffs it may not be necessary to don cylinders in the water. However, many divers prefer to remove their scuba units, along with weight belts, before climbing back on board. The outboard motor can often be an effective stepladder for climbing back into the boat, but a better choice is a fixed, sturdy ladder with flat rungs that extends into the water. The engine should usually be shut off before anybody enters the water. Occasionally currents, sea conditions, or lack of an anchorage make it necessary to drop off divers while the boat is moving. This is called liveboating. It should not be attempted without considerable training under supervision of all concerned, including the boat crew. The divers should be ready to exit as soon as the skipper announces arrival at the site. Then the engine is placed in neutral and, on command, the divers execute a backward roll. They should immediately swim clear of the boat to allow the skipper to move out of the area. Before returning on board, swim well clear of any shallow reefs or obstructions, because boarding will take longer than the entry. The boat is vulnerable to running aground while drifting without power. Do not approach the boat until the skipper signals you that the engine is in neutral. Remove your scuba unit, hand it to someone on the boat, then climb aboard quickly as soon as you are given the order. This is a special procedure that requires considerable practice and experienced boat handlers. RUNABOUTS, CABIN CRUISERS, AND LARGER YACHTS Runabouts come in a wide variety of layouts and sizes, from those 6 m (20 ft) long with rudimentary cabins to those 9 m (28 ft), which is near the largest size that can be trailered. Trailer boats are limited by beam (width) rather than by length on U.S. Interstate highways. As with skiffs, boats designed for fishing generally make the best dive boats. For ease in boarding, there should be no rail around the rear of the deck. On larger boats with inboard engines, a step-through gate is desirable. Many runabouts are powered by automobile engines, converted for marine use with an outdrive (referred to as an inboard-outboard). Because of their seaworthiness and greater fuel capacity, the effective range of these boats extends to over 80 km (50 mi). They are dry riding, allowing divers to travel fully clothed, in comfort, to and from the dive site. The owner will have many important decisions to make regarding deck space versus comforts. A bewildering array of options is available that can quickly deplete a budget. However, some are essential for a dive boat. These include a VHF radio, a good fathometer (depth measuring device) to find reefs, and a swim step to make it easier to get back on board. Also highly recommended are strakes, which are horizontal ribs that run along the hull, to deflect spray and make the ride smoother. Another desirable accessory is a LORAN navigation unit, or a GPS (Global Positioning System) unit, which uses electronic coordinates to help you return to favorite dive spots without long fathometer search runs. Although there is more room to move about on this FIGURE 12-2. INFLATABLE DIVE BOAT
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