 Externally, lift wires prevent the wings from folding up, and run from the underside of the outer wing to the lower wing root.Conversely, landing wires prevent the wings from sagging, and resist the forces when an aircraft is landing, and run from the upper wing centre section to outboard on the lower wings.Additional drag and anti-drag wires may be used to brace the cabane struts which connect the fuselage to the wings, and interplane struts, which connect the upper and lower wings together.