Tension-torsion strap comprising a plurality of laminae stacked one on top of the other along an elevation axis, each lamina comprising, successively along an extension axis, a body portion, then a distal connection portion, then a distal portion, which portions respectively form a layer of a body and of a distal connection region and of a distal fastener of the tension-torsion strap, the distal fastener comprising a fixing means for fixing said distal fastener to a blade, said tension-torsion strap extending in thickness along an elevation axis orthogonal to the extension axis from a first face of a lamina to a second face of another lamina, the tension-torsion strap comprising a periphery provided with an edge extending in elevation from the first face to the second face, each body portion extending transversely from one part of said edge referred to as "first side edge " to a part of said edge referred to as "second side edge ", each distal connection portion extending transversely from one part of said edge referred to as "first distal connection edge ", which extends the first side edge of the lamina, to a part of said edge referred to as "second distal connection edge ", which extends the second side edge of the lamina, each lamina comprising in said distal fastener a portion of said edge referred to as "distal end edge ", which extends from the first distal connection edge to the second distal connection edge of the lamina, said laminae forming at least one wide laminated element and one narrow laminated element (6, 7): - said body portions being stacked and identical in the region of said body, each body portion having a body width parallel to an axis orthogonal to the extension axis and the elevation axis, said body width being at a minimum in the region of a centre of the body, said body width increasing longitudinally in a first direction from the centre to the distal connection region and in a second direction opposite the first direction, said body width of a lamina being at a maximum in the region of an interface section with the distal connection region, - said distal portions being stacked and identical in the region of the distal fastener, - each distal connection portion of a wide laminated element protruding laterally relative to the first distal connection edge and the second distal connection edge of each distal connection portion of a narrow laminated element (6, 7), - the first distal connection edge and the second distal connection edge of each lamina each following a non-circular, concave curve, the distal connection portion of each lamina having a distal width between its first distal connection edge and its second distal connection edge which increases in the first direction, characterised in that the body width varies continuously between the centre and the distal connection region, and in that the tension-torsion strap includes a shrink sleeve arranged around said body. - said body portions being stacked and identical in the region of said body, each body portion having a body width parallel to an axis orthogonal to the extension axis and the elevation axis, said body width being at a minimum in the region of a centre of the body, said body width increasing longitudinally in a first direction from the centre to the distal connection region and in a second direction opposite the first direction, said body width of a lamina being at a maximum in the region of an interface section with the distal connection region, - said distal portions being stacked and identical in the region of the distal fastener, - each distal connection portion of a wide laminated element protruding laterally relative to the first distal connection edge and the second distal connection edge of each distal connection portion of a narrow laminated element (6, 7), - the first distal connection edge and the second distal connection edge of each lamina each following a non-circular, concave curve, the distal connection portion of each lamina having a distal width between its first distal connection edge and its second distal connection edge which increases in the first direction,