Wing spar splice joint

A wing spar joint for coupling the inboard ends of a right wing spar and a left wing spar, each wing spar comprising an elongated structural member including a planar web portion terminating in longitudinal edges, a top chord and a bottom chord extending from the longitudinal edges of the web portion, the top and bottom chords terminating in longitudinal edges and including a flange integral with the longitudinal edge of each of the top chord and the bottom chord, the wing spar joint comprising:

• a forward fitting adapted to be disposed against the forward surface of the web portion of the wing spars and spanning the joint defined by the inboard ends of the wing spars;
• an aft fitting adapted to be disposed against the aft surface of the web portion of the wing spars and spanning the joint defined by the inboard ends of the wing spars;
• a spar cap, including an upper spar cap adapted to be disposed on the upper surface of the flange of the top chord, and a lower spar cap adapted to be disposed on the inner surface of the flange of the top chord, the upper spar cap and the lower spar cap spanning the joint defined by the inboard ends of the wing spars;
• a lower chord fitting adapted to be disposed adjacent the lower chord of the wing spars, the lower chord fitting spanning the joint defined by the inboard ends of the wing spars;
• a strap member adapted to be disposed between the lower fitting and the lower chord of the wing spars spanning the joint defined by the inboard ends of the wing spars;
• a first plurality of fasteners inserted through mating holes in the forward fitting, the web portion, and the aft fitting so as to secure the forward fitting and the aft fitting together through the web portion of the wing spars;
• a second plurality of fasteners inserted through mating holes in the upper spar cap, the upper chord, the lower spar cap and the forward fitting for securing the upper spar cap, the lower spar cap and the forward fitting together through the upper chords of the wing spars;
• and
• a third plurality of fasteners inserted through mating holes in the lower chord fitting, the strap member, the lower chord and the forward fitting for securing the lower chord fitting, the strap member and the forward fitting together through the lower chord of the wing spars,
• wherein the forward fitting, aft fitting, spar cap and strap member are secured together with the wing spars to form a rigid connecting joint at the inboard ends of the wing spars.