Patent ID: 8161619

Claim:
A method of providing a fail-safe load path for a torque tube in an aircraft, the method comprising: providing the torque tube, the torque tube comprising: a composite tube comprising: a body having a body interior diameter and a body exterior diameter and including an end having an edge, the body interior diameter and the body exterior diameter being constant along the end of the body to the edge thereof; a wall thickness; and a set of helically-shaped grooves, each groove of the set of grooves disposed through a portion of the wall thickness, each groove of the set of grooves beginning at the edge and ending in the body, each one of the grooves including bearing surfaces; an end fitting comprising: a sleeve configured to mate with the body interior diameter; a set of ribs configured to mate with the set of helically-shaped grooves, each one of the ribs including bearing surfaces corresponding to the groove bearing surfaces; and a sheath being integral with the sleeve and having a constant sheath interior diameter configured to mate with the body exterior diameter, a portion of the body being sandwiched between the sleeve and the sheath; and adhesive installed within a gap between the rib bearing surfaces and the groove bearing surfaces; and securing a first end fitting of the torque tube to a first component in an aircraft load path.