Drive train

A drive train for helicopters, which comprises at least one engine capable of supplying mechanical power, a reduction gear and a main gearbox designed to drive in rotation the rotor(s) of said helicopter, the reduction gear comprising an output shaft, driven in rotation by said engine and coupled in rotation with the input shaft of said main gearbox, the reduction gear being housed in a housing in two assembled parts, called the “front housing” and the “rear housing”, said output shaft being supported and guided in rotation by several rolling bearings mounted in said housings, wherein said drive train further comprises a mount, designated “redundant”, and wherein said redundant mount is disposed around the output shaft and between a wall of said main gearbox and the front end of the front housing, and wherein said redundant mount is configured, dimensioned and attached to said wall of the main gearbox and to the front end of the front housing so as to create, in the event of rupture of said front housing, a secondary load absorbing path passing through this redundant mount, through the output shaft of the reduction gear and through said rolling bearings.