Portage Considerations

A fully laden Winsome is too heavy for her crew to lift or carry any distance. Fortunately, she fits well on any open (Canadian) canoe trolley. These will easily take the weight because they are designed to carry large canoes with their considerable cargo. As with a canoe, you do need to make sure that the boat is centred on the trolley, and lash the boat to the trolley so that it stays that way.

There are two portage scenarios we have tried:

1. (Storing and) Wheeling the boat from home or car park to slipway.
2. Extracting the boat from a canal to carry round locks.

In both cases, one is dealing with the complete, ready-to-sail, hull. This is probably too heavy for most couples to manhandle, so a trolley is essential. Whenever the boat is out of water, it really is better off resting on something, and a trolley serves that purpose, as you can see from the first photograph. If you have to keep your boat out of the water, but are lucky enough to have a river or canal at the end of your garden, you could probably get away with leaving her on the lawn on her side, but otherwise you need something to keep the hull off the abrasive ground.

If you don't need to transport the boat any distance on land other than on a trailer or roof rack, you can consider manhandling the empty hull. This weighs about 120 pounds, but is quite easy for two people to lift and carry short distances. Once the propeller and rudder are fitted - which you can do on the trailer or roofrack - you can put the boat in the water and fit the "engine" and seats while afloat. This is a little more fiddly than doing it on a trolley, but not much.

But if, like us, you live 2oo yards from the nearest launch point, or if you want to scoot past a fleet of narrow-boats passing through a flight of locks (yawn), then you need something that will carry a fully laden boat, whatever it is has to fit in the boat, and you need to consider how to get the boat in and out of the water.

The system we have developed consists of a Canadian Canoe trolley (currently we're using an Eckla one, but anything that will take the weight will probably do), an inflatable boat roller, and a hand pump (optional) to inflate the roller quickly.

The fully laden boat can be launched over the bank directly from the trolley, but it's harder to do recover the boat from the water that way. The roller is used to extract the boat from the water. You need to beach or come alongside somewhere you can reach down, grab the foot of the bow, and lift her out of the water onto the roller. If you can do that, you can then haul the boat ashore, pushing down on the bow to lift the (heavier) stern clear of the water and the bank. You then have your boat ashore and dripping, her bow resting on the ground and the roller just under the propeller shaft.

Now you may need to manoevre her a little so that the roller is well forward of the middle of the boat, enabling you to lift the stern and your partner to place the trolley underneath the boat just aft of the centre of gravity (which in a fully laden boat will be about a foot astern of mid-ships). Make sure the boat is centred on the trolley and aligned. The second picture shows the boat recovered from the canal and resting on the tolley and the roller. You can then lash the boat onto the trolley and remove the roller. You can do this with a single 6M cambuckle lash, but the lashing needs to go twice round the boat about a foot apart because it not only has to keep the boat on the trolley but also keep her aligned. When you hit bumps and rocks on the road, the trolley has a tendency to twist if not lashed down tightly. and if you aren't careful you end up "crabbing".

With the trolley in place and the boat lashed down, one person can wheel a Winsome by bearing down gently on the stern to raise the bow and pushing her forward. You do need to think about keeping the bow off the ground, and also about the length of the boat, but it's otherwise fairly easy and we've bypassed a lock flight of nearly a mile in this way, saving ourselves at least an hour. The length of the boat means you need to plan your turns (especially when going under bridges on canal towpaths) because the boat overhangs about 9 feet in front of her only contact with the ground. But after you've side-swiped your first toddler into the water you will quickly get the hang of it.

Why not have multiple gears?

We have tried different gear ratios on Winsome during the last 18 months. The gear box itself is fixed at 1:2, but by using different sized cog wheels on the pedal units, we can change the overall ratio from about 1:6 to about 1:9. The difference this makes is interesting - especially if you don't know anything about how boat propulsion works.

The "cruising speed" of Winsome is about 4 miles an hour. You can make her go at 5.5 miles an hour if you give it a bit of welly, and a very strong crew might manage the absolute maximum of about 7 miles an hour for a short time before exhausting themselves. The interesting thing - if you've only pedalled bicycles before - is that none of these figures is determined by the gearing!

Winsome goes at her 4 mph cruising speed at 300 rpm on the propeller. The effect of the gear ratio is simply to change how fast you have to pedal and how hard you have to push to maintain that speed. This is a personal preference for the customer. The first production boat, for example, will have quite a low 1:6 ratio. This means pedalling at about 50 rpm to sustain the cruising speed of 4 mph. For most of this year, we've been using a ratio of about 1:7.5, which requires about 40 rpm on the pedals to maintain cruising speed. The first ratio we used was about 1:9, and that needed only around 33 rpm, a leisurely pace that only I seem to have liked. Obviously, the work needed to keep the boat moving at a given speed is the same, so to cruise at 33 rpm you have to push harder than you do when cruising at 50 rpm.

We have had several cyclists try the boat, and most are convinced that what she needs is a decent set of gears. While impressed with how fast she goes, they insist that with decent gears they could have achieved twice the speed that they did. And with a proper gear box, they argue, you could start with a low ratio until you get going, then change up.

We'd rather not have variable gears, because any gear changing system introduces drag, and we don't have a lot of power to play with if we want a Winsome crew to be able to talk to each other and enjoy the ride. Gear shift mechanisms also introduce cost and complexity. But the main reason we're ignoring the cyclists is that they're wrong - the boat could not be made to go any faster with gears. Gears only control how quickly you have to pedal, and how hard you have to push, to sustain a particular speed, and the range of speeds that Winsome can achieve isn't wide enough to need a higher gearing to keep pedalling rates within human capability.
The "right" gear ratio is simply the one that is optimum for the crew in terms of rate and pressure at the speed they intend to go. There is an optimum speed where the pedals feel as though they are just about keeping pace with the boat. This speed, which I have referred to as the "cruising" speed above, is just over 4 mph.

The power Winsome requires to propel her at 4 mph is probably about 200 watts. The theoretical power curve in the diagram above is for a propulsion system with no drag at all - an ideal you cannot actually achieve. This ideal power system requires only 100 watts to maintain 4.2 mph, but the power-speed curve starts to head skywards above that. So, for example, it requires double the theoretical power to achieve 5mph, and nearly 4 times the power to achieve 6mph. Winsome's so-called "hull speed" - the practical limit on the speed of any boat whose hull is immersed in the water as distinct from planing on top of it - requires 6 times the cruising power. The theoretical 600 watts required to reach hull speed translates to well over a horsepower (765 watts) in the real boat, and it would require a couple of very strong men to deliver that!

This is where boats differ from bikes. The terminal velocity of a bike - the speed beyond which you require huge amounts of power - is determined by air resistance. If you can pedal fast enough, and push hard enough, you can drive a bike to higher and higher speeds with relatively small increases in pedal speed and force. Even so, a cyclist would struggle to reach half the terminal velocity of his bike, even with 21 different gears, whereas the Winsome pedaller can reach half the terminal velocity of his machine using only one gear, literally without breaking sweat!

Winsome Technical Details

Winsome is a two person, pedal-powered launch. She's just over 17 feet long and 3 feet wide, and cruises at 4 mph. Her maximum speed is around 7 mph, but that requires unsustainable effort on the part of the crew, whereas you can maintain 4 mph seemingly for hours on end. The two pedal units are 90 degrees out of phase, so that one or other of the crew is always on a power stroke, reducing overall effort and eliminating the need for any kind of fly-wheel. Winsome is designed to achieve her cruising speed on a continuous power input of about 250 watts - 125 watts per person - and the effort required is comparable to cycling on level ground at a wobble-free speed. Cruising in Winsome is less taxing than walking the same distance, and does not inhibit conversation, for example.

The pedals drive the propeller through a custom gearbox with patented lubrication-free nylon crown gears that are virtually silent. The gear box has a 1:2 input output ratio, and the pedal mechanisms offer a further 1:3 to 1:4.5 ratio making a total of between 1:6 and 1:9. To drive Winsome at cruising speed requires a prop speed of between 300 and 350 rpm, so customers can choose between a reasonably fast pedal cadence of 50 rpm or a fairly slow and heavy one of about 35 rpm by their choice of cog. Keen cyclists, for comparison, prefer a cadence of between 80 and 90 rpm, but keen cyclists generally proceed at a brisk and aerobically taxing pace.

Winsome's propeller is 12" in diameter with an 18" "pitch" - the theoretical distance moved by the propeller tip in one complete rotation. The propeller is a resin casting delivering reasonable weight for its manufacturing cost. The propeller - pictured above - is designed for robustness and to shed weed and other debris as far as that is feasible.

The boat is steered using a finger-tip fore and aft tiller mounted under the right hand of the forward facing crew member, connected to a balanced rudder. The boat is extremely manoeuvrable both forwards and when going astern.

Winsome was designed to be transported to, launched on and recovered from rivers, canals, lakes and broads. The adjustable seats, pedal mechanism, gear box and rudder can all be removed from the boat, leaving a bare hull weighing around 55 kg which can be loaded on the roof rack of an estate car. Fully laden she weighs just over 70 kg, and can be wheeled on a canoe trolley along towpaths, around locks and to and from a car park or home.

Welcome to the Winsome Launch Blog

This weblog was created for owners and potential customers of the Winsome pedal launch. This has been under development by Swallow Boats of Cardigan, Wales, for nearly three years, and will officially go on sale at the end of September, 2006. The hull design and propulsion mechanics were settled 2 years ago, allowing a a prototype Winsome to be built, extensively tested and exhibited at boat shows.

The production boat - pictures above - is slightly lower and sleeker than the prototype, and is made of glass fibre sandwich for lightness, strength and low maintenance. Official technical and sales information can be found on the boat builders web site at www.swallowboats.com. This web log is where we hope testers and customers will share practical experiences of using the boat.