An aircraft, comprising: an aircraft fuselage having a plurality of frame members and an outer skin; a vertical stabilizer having a multi-spar box, the multi-spar box including a front spar, a rear spar, at least one mid spar positioned between and spaced apart from the front and rear spars (45, 50), a first side skin extending between the front and rear spar, and a second side skin, opposite the first side skin, extending between the front and rear spar (45, 50), the front and rear spars (45, 50) and the first and second side skins (60A, 60B) defining an interior of the multi-spar box; a base rib assembly positioned in the interior of the multi-spar box and secured to the multi-spar box, the base rib assembly having a pair of opposing front longitudinal lugs, a pair of opposing rear longitudinal lugs, and at least one pair of opposing middle longitudinal lugs (150, 155) disposed between the front longitudinal lugs and the rear longitudinal lugs; a pair of front clevises corresponding to the pair of front longitudinal lugs, the front clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each front clevis having a first mounting arm, a second mounting arm, and a third mounting arm; a pair of rear clevises corresponding to the pair of rear longitudinal lugs, the rear clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each rear clevis having a first mounting arm, a second mounting arm, and a third mounting arm; a pair of middle clevises corresponding to the pair of middle longitudinal lugs (150, 155), the middle clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each middle clevis having only a first mounting arm and a second mounting arm; and a plurality of retaining members inserted through mounting holes (132, 142, 152, 157) in each front, middle, and rear longitudinal lugs (130, 140, 150, 155) and through mounting holes (242, 267, 282) in each corresponding front, middle, and rear clevises (220, 245, 270) to secure the vertical stabilizer to the aircraft fuselage. an aircraft fuselage having a plurality of frame members and an outer skin; a vertical stabilizer having a multi-spar box, the multi-spar box including a front spar, a rear spar, at least one mid spar positioned between and spaced apart from the front and rear spars (45, 50), a first side skin extending between the front and rear spar, and a second side skin, opposite the first side skin, extending between the front and rear spar (45, 50), the front and rear spars (45, 50) and the first and second side skins (60A, 60B) defining an interior of the multi-spar box; a base rib assembly positioned in the interior of the multi-spar box and secured to the multi-spar box, the base rib assembly having a pair of opposing front longitudinal lugs, a pair of opposing rear longitudinal lugs, and at least one pair of opposing middle longitudinal lugs (150, 155) disposed between the front longitudinal lugs and the rear longitudinal lugs; a pair of front clevises corresponding to the pair of front longitudinal lugs, the front clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each front clevis having a first mounting arm, a second mounting arm, and a third mounting arm; a pair of rear clevises corresponding to the pair of rear longitudinal lugs, the rear clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each rear clevis having a first mounting arm, a second mounting arm, and a third mounting arm; a pair of middle clevises corresponding to the pair of middle longitudinal lugs (150, 155), the middle clevises extending through corresponding apertures in the outer skin and secured to one of the plurality of frame members, each middle clevis having only a first mounting arm and a second mounting arm; and a plurality of retaining members inserted through mounting holes (132, 142, 152, 157) in each front, middle, and rear longitudinal lugs (130, 140, 150, 155) and through mounting holes (242, 267, 282) in each corresponding front, middle, and rear clevises (220, 245, 270) to secure the vertical stabilizer to the aircraft fuselage.