This relatively large workboat was required to function with small engines but,
nevertheless, carry a good payload. She also had to have waterjet propulsion
for shallow water and diver safety. I am a great believer in the Sea Sled shape
for carrying loads on the plane but the shape does swallow considerable amounts
of air under the hull which is death to the functioning of waterjets. A central
pod was added to get over the problem and the lines were also modified to allow
efficient low speed running when off the plane.
The objectives were achieved and the craft handled well.
I believe the Sea Sled is a better shape than the more
familiar catamaran for giving a stable platform
and carrying loads on the plane. Cats are fine when relatively light but draught
increases rapidly with load and drag increases – particularly if the
bridge deck hits the water.