Ikarus IO
 The Ikarus IO (Serbian Cyrillic:Икарус ИО - Извиђач Обални) was a biplane flying boat produced in Yugoslavia in the late 1920s. It was a conventional flying boat design for its day featuring a large single-bay wing cellule the staggered wings of slightly uneven span braced with N-struts. The pilot and observer sat side by side in an open cockpit and a gunner sat in an open position ahead of them on the bow. The pusher engine and frontal radiator were carried on struts in the interplane gap.