Parametric analyses and design refinement studies were performed for conventional, canard, and spanloader aircraft configurations to determine the lightest ramp weight configuration with a nuclear propulsion system. Mission requirements for these analyses were: 400,000 and 600,000-lb payloads, 0.75 cruise Mach number, 1000 n.m. emergency chemically-fueled range, and a 9000-ft field length. The canard configuration was between one and ten percent lighter in ramp weight than the other candidates at both ...