Note: Sent this last night but it appears to have not gone through or was restricted to size. After multiple attempts on Joe's and my part to get this loaded, now breaking it into 4 parts. Part 4 of 4 12. Buoyancy sled a) Tire around sail i) Pros: (1) Simple solution ii) Cons: (1) Only solves issue of snap roll during towing (2) Doesn't address ramp launching/recovery issues. (3) Still have to get to the channel and dive site b) Inflatable collar around lower hull i) Pros: (1) Decreases draft of submersible to aid ramp launching/recovery. (2) Meets requirements for: (a) Shallow water ramp launch/recovery (b) Maneuvering in skinny water (3) With significant decrease in draft, towing speed and handling should improve ii) Cons: (1) Removal prior to diving will be problematic (2) It will be even more difficult to reattach at the end of the dive due to its flexible nature and trapped air in a varying sea (3) Subject to puncture and thus stranding the submersible in a busy passage way or even damage (4) Still have to get to the channel and dive site (5) Towing tracking issues can be expected (6) Where to get a custom inflatable fabricated? c) Pontoon collar i) Pros: (1) Decreases draft of submersible to aid ramp launching/recovery. (2) Meets requirements for: (a) Shallow water ramp launch/recovery (b) Maneuvering in skinny water (3) Relatively simple solution (4) With significant decrease in draft, towing speed and handling should improve (5) More durable than an inflatable collar (6) Easier removal and reattachment at the dive site (7) Fabrication should be easy (8) Simple solution ii) Cons: (1) Still have to get to the channel and dive site (2) Towing tracking issues can be expected d) Semisubmersible pontoon boat i) Pros: (1) Meets requirements for: (a) Shallow water ramp launch/recovery (b) Maneuvering in skinny water (2) Should be a reasonably cost solution (3) Relatively easy to construct (4) Have constructed an unpowered one for salvage from 55 gal. poly drums, 8" x 8" wooden beams, stainless steel strapping, and carriage bolts (5) If powered by outboards, bow can designed to be semisubmersible (6) If towed, stern should be designed to be semisubmersible (7) Vessel available for other applications ii) Cons: (1) Only safe to operate in relatively protected seas e) Semisubmersible planing sled (see Flickr reference at end) i) Pros: (1) Previously built by Perry Submersibles in early 70s for Cubanaut operations (depicted in Skin Diver about 1974) (2) US Army and the Navy's SEALs have used similar designs (surplus sleds may be available for modification) (3) Meets requirements for: (a) Shallow water ramp launch/recovery (b) Maneuvering in skinny water (4) Potentially quick delivery to dive site (5) Can be built so no additional personnel are required for launching and recovery other than the sub pilot (6) Vessel available for other operations (7) Functional in higher sea state ii) Cons: (1) More costly solution if not using a salvaged or surplus hull (2) Daily operations at high speeds have increased costs due to high fuel consumption rate f) Submersible sled (i.e. LRT) i) Pros: (1) At sea launch/recovery docking of the submersible happens at depth avoiding the issues of sea, wind, and possible lifting at the surface (2) Meets requirements for: (a) Shallow water ramp launch/recovery (b) Maneuvering in skinny water ii) Cons: (1) Requires support divers (2) Complicated air delivery system (3) Diver killed during LRT ops and believe this method of recovery has now been abandoned in Hawaii (4) Failure of the LRT could result in dragging the attached submersible down with it. Recently rendered images of the semisubmersible planing sea sled and travel lift trailer have been loaded at: http://www.flickr.com/photos/bottomgun/ While no solution is outstanding in resolving operations in the skinny waters associated with Florida waters, I tend towards the powered, semisubmersible, planing sea sled or Kittredge's 40-ft. steel tender. A distressed or 2nd hand fiberglass boat could probably be modified into a sea sled. Plans for George's tender use to be $100 and he stated that it only took 2 of them two weeks to cut the hull plates and form up the rough hull. He and his wife navigated the tender from Maine to Florida and back for the winter with a K-250 on the stern ramp. With a small diesel it should be economical to operate. Respectfully, Jay K. Jeffries Andros Is., Bahamas Mankind have a great aversion to intellectual labor; but even supposing knowledge to be easily attainable, more people would be content to be ignorant than would take even a little trouble to acquire it. - Samuel Johnson
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