It’s not unusual to see the words “street art” and “abandoned” in the same sentence. Deserted factories, disused train carriages and even abandoned towns have been given new leases of life at the hands of talented graffiti artists. Still, there always seem to be new types of forsaken objects and places to fuel the imagination. For “The Boneyard Project: Return Trip” exhibition at the Pima Air & Space Museum in Tucson, Arizona, the canvases were surplus military airplanes.