An aircraft structure comprising: a base , the base having an exterior surface and an opposite interior surface, the base having a longitudinal length between an inboard edge of the base and an opposite outboard edge of the base; a first stringer , the first stringer having an exterior surface and an opposite interior surface, the first stringer having a longitudinal length between an inboard end of the first stringer and an opposite outboard end of the first stringer, the exterior surface of the first stringer is secured to the interior surface of the base with the longitudinal length of the first stringer aligned with and extending along the longitudinal length of the base; a second stringer , the second stringer having an exterior surface and an opposite interior surface, the second stringer having a longitudinal length between an inboard end of the second stringer and an opposite outboard end of the second stringer, the exterior surface of the second stringer is secured to the interior surface of the base with the longitudinal length of the second stringer aligned with the longitudinal length of the first stringer and with the longitudinal length of the second stringer aligned with and extending along the longitudinal length of the base; the first stringer is longitudinally spaced from the second stringer; the base connects the first stringer to the second stringer and only the base connects the first stringer to the second stringer; the first stringer has a first cross-section configuration; the second stringer has a second cross-section configuration; and, the first cross-section configuration and the second cross-section configuration are different configurations. a base , the base having an exterior surface and an opposite interior surface, the base having a longitudinal length between an inboard edge of the base and an opposite outboard edge of the base; a first stringer , the first stringer having an exterior surface and an opposite interior surface, the first stringer having a longitudinal length between an inboard end of the first stringer and an opposite outboard end of the first stringer, the exterior surface of the first stringer is secured to the interior surface of the base with the longitudinal length of the first stringer aligned with and extending along the longitudinal length of the base; a second stringer , the second stringer having an exterior surface and an opposite interior surface, the second stringer having a longitudinal length between an inboard end of the second stringer and an opposite outboard end of the second stringer, the exterior surface of the second stringer is secured to the interior surface of the base with the longitudinal length of the second stringer aligned with the longitudinal length of the first stringer and with the longitudinal length of the second stringer aligned with and extending along the longitudinal length of the base; the first stringer is longitudinally spaced from the second stringer; the base connects the first stringer to the second stringer and only the base connects the first stringer to the second stringer; the first stringer has a first cross-section configuration; the second stringer has a second cross-section configuration; and, the first cross-section configuration and the second cross-section configuration are different configurations. <EOS>