Three-engined flying boat, development of the MDR-3 redesigned under A.N.Tupolev's supervision. Two tandem engine pairs of the MDR-3 were replaced by three (two tractor and one pusher) M-34R engines. Wing struts eliminated, wing area increased. Tail surfaces area was also increased, tail was raised like on the MK-1/ANT-22. The hull was almost identical to the MDR-3. Wing had mixed cover - aluminum on inner section, fabric on outer panels.
|Engines||3*750/830hp Mikulin M-34R|
|Speed at 0m||232km/h|
|Speed at ***m||211km/h|