Spira international wooden boat plans. following are the stock plans available for the various types of boats, separated into the different categories.. All power boats 16′ long and under. tech support. the best technical support: we will help you succeed! all our plans and kits come with full technical support.. Boat plans for the 15 "i finally finish my 15′ dinghy from your plans. today, my son and i took the dingy out on her first main voyage..