The Udet U 12 Flamingo was an aerobatic sports plane and trainer aircraft developed in Germany in the mid-1920s.
The U 12 was a conventional, single-bay biplane of wooden construction with the wings braced by large I-struts.
The U 12 proved extremely popular and sold well, due in no small part to Ernst Udet's spectacular aerobatics routines while flying the aircraft.
One particularly acclaimed part of his act included swooping down towards the airfield and picking up a handkerchief with the tip of one wing.
[1] The popularity of this aircraft was insufficient to rescue Udet Flugzeugbau from its dire financial position, but when the company's assets were taken over by the state of Bavaria to form BFW, production of the U 12 soon resumed in earnest.