High-fidelity aerodynamic optimization based on the Reynolds-averaged Navier–Stokes (RANS) equations is used to investigate the aerodynamic performance of the Flying-V aircraft configuration in the twin-aisle and single-aisle classes. Lift-constrained drag minimization is performed at the start-of-cruise operating point with the aircraft planform fixed and free. Aircraft weights are estimated using empirical methods. The planform-fixed case has design freedom in section shape and twist, while planform-free cases add chord, span, and sweep angles. At a cruise static margin of 6% and an altitude of 13,000 m, exclusive of nacelles, pylons, and excrescences, the optimized fixed-planform twin-aisle-size Flying-V aircraft produces a cruise lift-to-drag ratio of 25.5. Planform optimization, which reduces chord and sweep and increases span, enables a cruise lift-to-drag ratio of 26.7 at the same altitude. The optimized single-aisle-size Flying-V aircraft produces cruise lift-to-drag ratios of 20.2 and 23.2 at altitudes of 10,973 and 13,711 m, respectively, again excluding drag contributions from nacelles, pylons, and excrescences. High-fidelity aerodynamic optimization shows that the Flying-V aircraft is capable of excellent aerodynamic performance at cruise. Strong shocks are absent on all optimized designs. The configuration excels in the twin-aisle class and attains sufficient aerodynamic performance at the single-aisle size to justify further study.
Yazdi et al. (Mon,) studied this question.