A wing airframe for a wing of a tiltrotor aircraft includes a wing airframe core assembly and a wing skin assembly disposed on the wing airframe core assembly. The wing skin assembly includes a lower wing skin assembly disposed on the bottom side of the wing airframe core assembly. The tiltrotor aircraft includes a fuselage underneath the wing. The lower wing skin assembly has one or more buckle zones outboard of the fuselage. The buckle zones are locally susceptible to buckling in response to an impact of the tiltrotor aircraft, thereby protecting the fuselage from being crushed by the wing.