19 hydroplane boat plans, instant access download! simple easy to build small inboard and outboard boat plans. perfect for the backyard boat building enthusiast.. The dyno jet utilizes the popular jet pump powering system. there are plenty of "jet skis" that have suffered hull damage but the propulsion system is still in good. Didi mg30 built by tamas csaba in hungary . our stock design file . click on design links below to see more info. go to pricelist for plans & study packs.