There's an 18 foot sailboat I am interested in buying but it has a
fixed keel of about 3.5 feet. I've only had boats with a swing keel.

Can a boat with a fixed keel like this be LAUNCHED from the trailer or
does it require a crane to sling it into and out of the water?



Here is an idea....

Lets say your trailer has a retangular frame outline....8 foot wide by 20 feet
long.

And the frame is at the same level as the axle, which for normal size tires
will be about a foot.....now of course if you use smaller diameter tires or
dont have an axle you can probable get the frame down to 6 inches from the
ground...

Now, excluding the area for the tires and a "channel" down the center for the
keel, you have about 100 square feet left to work with at the four corners of
the trailer.

Now, build flotation chambers onto the frame bottom, making them about a foot
tall. If you have your trailer made, the welder can just well angle iron to
form the edges of the flotation chambers. Then bolt on plywood to the sides,
tops, and bottoms.

Make these chambers were they can flood quickly and easily when needed.

Lets assume the boat is already in the water, but some distance from the ramp.

Back the trailer into the water. Unattach it from the tow vehicle. The chambers
are air filled and trailer now has about a 1.5 foot draft.

Float the trailer over to the sailboat. Flood the chambers. The trailer is
designed so that it still has a couple hundred pounds of flotation even when
completely flooded (ie some foam here and there), so you can stand on it if
need be.

The trailer is designed so that when its flooded, it is at the right depth and
orientation that the sailboat can "sail" right up on it.

Float the boat onto the submerged yet floating trailer. Strap/secure her tight
to the trailer. Pump out the flotation chambers. Use high volume, low head
pressure pumps to do this quickly.

When its pumped out, the trailer will have a draft of 2 feet, or less if you
optimise the design.

Those 4 chambers that are 1 foot tall will float over 6000 pounds! (100 square
feet times 1 foot tall = 100 cubic feet, times 60 lbs per cubic foot = 6000
lbs).

Drive the boat/trailer back to the ramp, reattach to tow vehicle, and pull outa
the water...

Yeah, it would proably be dangerous and a pain in the ass if done wrong, but if
designed the right way, it should be a pretty workable solution.

It would also come in handy where not only is the ramp draft to shallow, but
the general launching area is as well, in which case you use this trailer to
get the boat out to deeper water.....

Heck, you could even forgo the trailer part...in some areas around here we have
docks, but even at the end of em its too shallow to keep all but the lowest
draft boats. But the decently deep water is usually only a few hundred feet to
a quarter mile further out.

So make what I described, except now it can be wider and longer (to make it
more stable. And it doesnt have wheels. Its really a floodable barge now. Now
you can keep your boat at the end of the dock even though its pretty shallow
there!

just an idea

take care

Blll