М-4 (On NATO codification: Bison - "Bison") - the first-ever jet strategic bomber which has arrived in armies. It was created simultaneously with Ту-95, differing from it in the big speed, but in smaller radius of action. For the purpose of weight reduction large-panel assemblage was used, that strongly complicated plane manufacture. As aerodynamically pure wing (absence of gondolas for the chassis and engines on a wing) and as consequence - the "bicycle" chassis which did unusually difficult planting of the plane and practically impossible modernisation of bombing compartments and use of an external suspension bracket was feature. For example charge АН602 has been dumped with Ту-95 because of its impossibility to deliver on М-4.