This canoe was specially ordered with the extra large sponsons so only the customer could tell us why. My guess is that they were particularly safety conscious and just wanted some additional flotation. The images below show the page from the 1947 catalog which describes sponsons, a page from the 1948 catalog showing some more typically sized sponson canoes including an 18 foot long Otca with twin sails, and that same Otca at the WCHA Assembly last year. Sponsons can be a good safety feature but they do add weight and take some extra time to restore. You will also probably want to remove the drops and bolt the bow seat directly to the gunwales for better mast support if you plan to sail it again. Have fun,
Benson