thunderboat

An unlimited class hydroplane, particularly one powered by a Second World War surplus V-12 fighter aircraft engine. Delightfully obnoxious for the awful racket they made, they are increasingly rare as availability of engines has dwindled to almost nothing. It was the Sound of Summer in places where unlimited hydroplanes were raced and could be heard for miles and miles.

"Bring your camera and some earplugs, we're going to the thunderboat races.