Powered outrigger canoe

Aloha! I'm new to this site and I must admit a lot of the things that I've read are over my head but I'm learning as I go. If anyone can point me in the right direction, I 'd really appreciate it. I'm trying to build a plywood outrigger canoe, maybe 18', that will hold two adults and run with maybe 5hp or less outboard engine and I can't figure what hull shape would best suit my needs. I'm looking for an easy build with either a flat-bottom vee shape like a Malibu outrigger or a rounded vee stitch and glue style like a Quattro 16. Which would be better under power? I don't need to go fast- 10 kts or less but I will be going out about 6-8 miles in open ocean so fuel efficiency is important since I'll be carrying about 6 gallons at most. Any comments/suggestions is greatly appreciated. Mahalo, Shinchan

 

Down in the Phillipines the powered outrigger canoe is known as a Banca Boat and are very common. Most are powered by an air cooled Volkswagen engine. For the building plans of an outrigger canoe, see "Selway Fisher Boat design. Paul Fisher has designed a couple of outrigger canoes and plans are available. Rigging it for power shouldn't be too difficult. An air cooled Briggs and Stratton engine or small outboard should do the trick for an 18 footer.

 

For ocean use I would definitely go with a round bottom so that you can roll with the waves if you get sideways to them. Flat bottoms are only good for rivers and lakes in a canoe, I wouldn't want a flat bottom at all in a canoe, thats for wide body jon boats. I built outriggers onto a canoe last summer and I found it helpful to have an adjustable height mechanism, so that you could adjust the point at which they hit the water according to the load. I think it is also a good idea to have a high sided, 20 inch transom canoe, whether you are in rivers or oceans, and use a 20 inch shaft outboard. The possibility of a stern wave or wake capsizing you is very real in a 15 inch transomed boat, I almost had it happen to me in shallow water once. For an 18 foot canoe you could go all the way up to 10 hp with no problem, even with a 15 inch transom, as long as it was a newer, lightweight outboard and you had a tiller extension. With a 20 inch transom, you could go up to 15 hp probably. There was a guy here in this town, Dick Cook, who used to put a 25hp on a 19 foot Grumman, but I don't recommend doing it. (He died from capsizing his canoe in 2001 by the way. He was written about in the book "Coming Into the Country" by John McPhee). Also, I would have a one-way check valve or some kind of way to get rid of moisture and vent air on your outriggers if they are sealed, because they will build up moisture, especially if they are glassed. Best of luck.

 

Mahalo for the information, I going to do more research and probably look to (slightly)modify a set of plans to include a small outboard. Thanks again, Shinchan