Nautical vehicle consisting of a central, tubular body (1) of fibre glass, hermetically sealed with a streamlined bow (2) in front and a bevelled zone at the back in the lower half which gives way to a keel. The upper plane of the vehicle has a longitudinal slot containing a seat (22). There are provided extending dismountable arms (23) at each side at the end of which are floats (24). In front of the seat (22) are provided a couple of pedals (9) connected via a cardan transmission and a reversing mechanism to a propeller.