The Gnosspelius Gull was a 1920s British experimental ultra-light monoplane designed by Major O.T.

Gnosspelius and built by Short Brothers at Rochester for the 1923 Lympne light aircraft trials.

[2] Tests using this had indicated that incorporating a small step into the upper surface of the wing at the point of its greatest thickness would reduce drag, and Gnosspelius had started work on the design of a small glider using this discovery when, in early 1923, two prizes intended to promote the development of light aircraft were announced.

The wing used the RAF 19 section, modified by the inclusion of a 3⁄8 in (10 mm) step in the upper surface.

Wide-span ailerons were hinged to the rearmost wing spar, operated by torque-tubes with dog clutches at the junction between the centre section and the removable outer panels.