The Dąbrowski D.1 Cykacz (Ticktock) was an unusual, small, low-powered, single-seat biplane, intended to provide wider access to flying.

Jerzy Dąbrowski's first aircraft design, produced early in 1924 while he was a student at the Warsaw Technical University, was an unusually clean biplane with an entirely wooden structure.

The whole fuselage was a smooth, oval section semi-monocoque structure with wooden frames and ply skin and the engine was in its forward part, though with its cylinders exposed for cooling.

The biplane's single, open cockpit was under the upper trailing edge where there was a cut-out to increase the pilot's field of view.

[1] When first tested, the Cykacz was reluctant to take off, partly because the Tomtit engine was unreliable and had to be kept below the high output shaft speeds for which the propeller was designed.