The single engine, high wing Moskalyev SAM-5bis-2 was a 1934 light transport developed into four more different types, of which the SAM-25 was the last.
The whole surface, including the ply-skinned leading edge, was fabric covered.
Behind the cabin the fuselage narrowed to the SAM-5bis-2-style tail, with a blunted triangular fin and more rounded rudder, though the latter was now fuller, with trim tabs.
A blunted triangular plan tailplane was mounted on top of the fuselage and carried rounded, tabbed elevators, separated for rudder movement.
[1] Data from The Osprey Encyclopedia of Russian Aircraft 1875-1995[1]General characteristics Performance