Fleet Videos of performance with Two Different Motors

As some of you already know, Fleet is a planing-hull derivative of my very successful Flint design. For some background you can look at this post and at this post.

Fleet awaiting more trial runs

Fleet was designed from the outset to perform well in the very speed/length ratio spectrum in which normal planing hulls are at their worst. By that I mean the so-called "semi-displacement" or "semi-planing" range - widely thought to be in the S/L ratio range of 1.5 to 2.5.

Speed/Length ratio is basically the speed of a boat (expressed in knots), divided by the square root of the waterline-length (expressed in feet) of the boat. So let us take Fleet as an example: -

• LWL (length on the waterline) equals 14 feet
• Assume S/L ratio of 2.5
• Speed divided by 2.5 equals 3.74 (i.e. square root of 14 ft LWL)
• Therefore, Speed in knots equals 2.5 times 3.74
• Speed equals 9.35 knots (10.8 mph, or 17.3kph)

Now those speeds sound modest, but for a small boat like Fleet it represents a very satisfying speed indeed. More importantly, because this hull has been proportioned to operate within this S/L ratio, the boat trims well, instead of pointing her bow in the air like the standard planing hulls, which chew fuel at a high rate just to pull a large wake.

So far Ive been able to carry out several test runs in Fleet using both a 9.8hp Tohatsu two-stroke and a 2hp Honda four-stroke. The 9.8hp Tohatsu is based on the powerhead from the 6hp and 8hp models, so is suitable for this light-weight boat. My next test will be using a 4hp motor, which I think is about the optimum size from an efficiency perspective. In my part of Australia, 4hp (2.9kW) is the largest motor allowed without boat registration.

Here are two Youtube clips - firstly using the 2hp Honda, with which I achieved a consistent 7.9 knots measured by GPS with my weight aboard, and 7.1 knots with my wife joining me (she only weighs 60kg/132lbs. The 9.8 Tohatsu gave 15.5 knots (17.8 mph or 28.6 kph) with two heavy men aboard plus gear.

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Flint and Alby Sailing Videos

Ive written a fair amount about a group of my designs which make use of a very simple boat-building method, know by a range of names including "Stitch-and-Glue", "Taped-Seam", "Tack-and-Tape", "Composite-Chine", and so on.

A taped-seam hull under construction - in this case a hull made from my First Mate design.

There are some significant advantages associated with this construction method, with notable ones being:-

• if properly designed, hull panels can be marked directly onto the sheets of plywood used in the boats construction;
• the builder can produce a "flat-pack" kit ahead of time, which allows those who have limited building space to get a head-start on the job;
• again, if the boat has been properly designed, accurately marked, and carefully cut, the hull can be built without a fixed strong-back and station mould assembly - a very significant saving in time and resources;
• the amount of timber framing in the hull can be reduced to a minimum, saving cost, reducing weight, and avoiding rot-traps - all without sacrifice in strength;
• the vulnerable edge-grain of the plywood is exceptionally well protected within a cocoon of thickened epoxy and glass firbes;
• sanding, painting, and maintenance are all made easier due to the clean interior (and exterior) of the hull.

Please do not get me wrong - I am not advocating this system over other methods of construction. All construction methods have advantages and disadvantages, and every boat design and building project must be carefully considered in the light of many compromises. What I am saying is that taped-seam/stitch-and-glue/composite chine should be given the respect that it deserves.

I continue to design boats to be built glued-lapstrake (glued-clinker), glued-strip-plank, cold-moulded, and taped-seam. Frequently the design itself determines which method will be the most appropriate, and it is very important that the builder understands the design, materials, and application very clearly. Education is the word!

Here are two video clips of taped-seam (stitch-and-glue etc) boats under sail.

The first is a clip shot by Paul Hernes, a Phoenix III owner-builder, showing a boat built to my Flint design by Paul McShea. Flint was designed primarily to be a rowing boat, but her hull shape assumes that some will feel the need to sail her, and/or mount a small outboard motor. The plans include details for a sailing rig, daggerboard and rudder. However, Paul McShea had a Heron rig on hand, and it happens to be just about the right size and shape for Flint.

https://vimeo.com/111257166

Ive also been able to shoot a short clip showing my Alby design under sail, showing-off her tanbark-coloured balance lugsail. There are plenty of eight foot long pram dinghies in the world, but what is important about Alby is that she has an unusually large carrying capacity, and due to the design of her chine-line, she is still able to travel quite fast while leaving a relatively flat wake. Both Alby and Flint have easily-driven hulls for their size.

This particular Alby carries a short foredeck, which is a variation from the plans - something I do not recommend.

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Videos Showing Details of Phoenix III Balance Lug Rig

During a recent visit from Paul Hernes (builder of the first Phoenix III) I was able to take a number of still and video shots of the details of the balance lug rig on Pauls Phoenix III.

This was my first ever attempt at video filming and editing, so please be patient with the results. However, you may find some of the clips to be worthwhile as they do show how well the boat has been developed by Paul over the years. Here they are: -

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