Index

Thoughts on Raising a Submerged SJ23, (perish the thought).

INDEX - Outside Flotation, Ping Pong Balls, Bladder, Crane, Legalities.

• Remember, safety first and take your time.  There is no hurry to recover the vessel, she isn't going anywhere!  There is absolutely no point in adding a second casualty to the list, the boat being the first one.
• Assess the situation first and see it for what it is, not for what you want.  Determine all the hazards and then make a recovery plan that works all the way to the surface.  This will take some imagination.  Be ready to modify the plan when things change, and they will.  If your SCUBA skills are up to snuff then I wish you luck.  Remember that the buddy system is crucial during recovery work.
• If you don't feel capable get help from competent SCUBA divers or a professional recovery company.   Let them assess the situation.  A sunken sailboat with rigging still standing could be dangerous to dive on.  Loose lines, sail bags, cushions and hoisted sails all contribute to possible snags that will complicate the recovery, especially if the water has limited visibility.
• Mark the recovery area with a huge "diver down" flag to keep other traffic away and ensure the safety of the divers.  Four flags at the perimeter mark the area much better than a single flag.
• Finally, keep a look out for gators and other nasty critters with teeth.

A fibreglass sailboat weighs less underwater than on above.  I wish I could tell you the exact weight of a submerged SJ23 but my S.W.A.G. calculates it to approximately 1000 lbs.  If anybody can calculate this, I'd be happy to place the "correct" answer here.  I have witnessed a few recoveries and all of them required different techniques based on the situation; boat size, construction & condition, water depth, clarity &  current, surface weather and finally debris on the bottom.  These are the main issues to take into consideration.  There are two times during a recovery that are very dangerous: the first is when the boat is approached (lots of unknowns) and the second is just at the joyous moment when the boat starts to rise.  This last one is particularly dangerous because it may be difficult to control the direction of the boat or the rate of ascent.  I once watched a 35' sailboat being raised 100' in clear water.  We were above it when it started to rise and barely got out of the way as it charged for the surface.  It is amazing how quickly it can come up from that depth.  Don't get under her and don't hang on for the ride. 

NYLON STRAPS WITH OUTSIDE FLOATATION - Use two yellow nylon straps (lime green or yellow are easiest to see under water) and four vinyl 33 Imperial gallon barrels.  Make a harness that consists of two 3" (or wider) cargo straps, one placed around the hull ahead of the keel and the other placed behind the keel. (Same location as for crane lifting).  Snug up the belly straps and close the clamps, securing them so they cannot come undone.  These straps will also add some strength to the hull by simply holding the deck and hull together which is important at the surface.  The straps must also be tied to each other below the gunwales to keep them from sliding off the ends as the barrels raise the hull.  The more secure these straps are the better since there will be a terrific lifting force.  You could sew these straps together into a harness so everything is positioned correctly, but it may complicate the job of positioning it around the hull.  Objects on the bottom have a way of blocking your best intentions.
Each belly strap must have a loop sewn to the side to attach a vinyl barrel.  Position the loop so the barrel is at the water line to ensure the boat stays upright at the surface.  This also creates some freeboard to facilitate pumping water out.  The barrels must have a 3" wide weight bearing nylon strap around it and some 1.5" wide webbing around the ends so it is held captive.  Use two straps for improved weight distribution and strength.  Each barrel could be attached to the belly straps using a heavy D ring, a clevis or a fabric loop sewn to the webbing.  Keep in mind the limited dexterity of the diver's hands.
Stability at the surface is very desirable to control the boat and to facilitate pumping.  It would be rather disheartening to see the boat slip down again after all the work of raising her.  I've seen two recoveries fail at this stage.  When the boat is stable at the surface you know your plan is working.  In the case of an SJ23, you might have to block off the rudder aperture to prevent water from flowing into the cockpit.

• Inspect all straps for damage and other weakness before use.
• Always protect the strap from a sharp edge.
• Do not tie a knot in a strap.  This greatly reduces the strength and is next to impossible to untie.
• Do not use a strap if there is any sign of a cut, chemical or heat damage, excessive wear, worn stitching or other defects.
• Look for an approval code (ie: manufactured is accordance with CSA or OHSA) to determine its load carrying capacity.
• A strap that has experienced a dropped load should not be used again.

If the sails are hoisted under water, lower them before the boat rises.  You don't need the steering effect while being raised not do you need the wind load at the surface!  Empty the boat as much as possible to eliminate complications.  Remove the outboard engine.  Fill the four barrels with air, each of them a little at a time, so they have equal floatation and the boat stands upright on the bottom.  The boat must rise with the hull in an upright, horizontal attitude.  The barrel fill hole must be at the bottom so expanding air can escape as the boat rises.  Plug the holes when the boat is at the surface.  Tie the plugs to the barrels, close to the fill holes.  Do not climb into the boat when it is at the surface.  This is a recipe for disaster.  Decide now if pumping is prudent or to tow the full boat to shallow water.  A submerged boat is a cumbersome object to tow.  This decision is very situation dependent.  Go very slowly.  If there are no holes in the hull, then pumping gains you immediate security and improved control.  An empty boat is very easy to tow and a great relief.  It might be prudent to tow it to shallow water where you can float her permanently with less fear of doing further damage.

PING PONG BALLS - I saw this technique on Discovery Channel, Myth Busters.  Love those guys.  They raised a 25' fibreglass keel boat by pumping ping pong balls into the submerged hull.  The underlying concern is that the hull and keel are lifted by the hull to deck joint, something it is not designed to do.  At right is a profile of the SJ23 hull to deck joint.  While it is very strong, it is not designed to raise a hull and keel.  Using just internal floatation works only if the hull to deck joint is very strong.  The Myth Busters had to secure a piece of 3/4" thick plywood inside the forward hatch to prevent the balls from popping out.  The companion way was also blocked off for the same reason.  A diver placed the end of the hose at the bow and then moved it to the stern to distribute the lifting force.  The maximum depth that a ping pong ball can withstand is 90.'  Below that it implodes.  The advantages of this technique are: the hull holds the balls very securely, air is not lost through a small hole, no floatation barrels to strap to the outside the hull to bump against things and the hull will be stable at the surface where the water can be pumped out.

BLADDER - Buying enough ping pong balls to lift an SJ23 is rather expensive.  Go to a sporting good store and do the math.  Bladders can be substituted since they are much easier for a diver to handle.  If the bladder inlets are extended to the companionway with air lines, they can be filled from a central location making the recovery work safer for the divers.  The air bladders must be capable of relieving air to prevent bursting as the boat rises to the surface.  This feature makes them expensive and gives you an idea of the forethought required to execute a lift.

CRANE - The boats are carried along the factory assembly line by the shroud and backstay chain plates.  So if you want to use a crane these attachment points are strong, but not infallible.  Failing that, place the slings ahead of and behind the keel and hoist away using a compression square above the boat to prevent crushing the hull.  Remember to tie the belly slings to each other at the gunwales to prevent them slipping off the hull ends. Once the boat is at the surface, the water must be pumped out before it can be lifted out of the water.  If not, the hull will break from the weight of the water, in which case the water will drain out!
 

MY FIELD OBSERVATIONS

LEGAL STUFF - There may be legal implications that prevent you from salvaging so you should contact your insurance company (or the other person's insurance company) and the proper authorities before you attempt to raise her.  I've heard that the insurance company automatically owns the boat and you must pay for salvage rights to raise her.  In other cases they simply want to be informed to notify the Coast Guard of a salvage operation.  Then there are environmental regulations regarding fuel and oil spillage.  Rules and regulations vary from one locale to another and it pays to know them in advance.

I've seen enough sailboats on the rocks or a beach but hope I never see an SJ23 on the bottom!  Good luck.
 

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