An improved trawl door that provides by combination of certain camber relationships of leading edge slats relative to a main deflector body, in certain aspect ratios, with certain thickness relationships for plates forming leading edge slats and a main deflector body where such leading slats and such main deflector body are formed with a similar curvature to their exterior (i.e. “outer”) and interior (i.e. “inner”) side surfaces, a trawl door that provides a maximally efficient trawl door of superior efficiency, of superior stability, useful at a wide range of angles of attack. In certain embodiments a perforate slat is disposed above a leading edge slat. In certain other embodiments, a perforated slat is disposed above a main deflector body, and certain constructions of support plates are useful for protecting the various perforated slats.
