The project showed the importance for gound handling to be robust. Gound handling is not the financial game changer in aircraft design. Span limitations for short-medium range aircraft of 36 m at airports drives the design (ICAO). The standard jet configuration can be optimized, if is Top Level Aircraft Requirements (TLAR) are challenged. Examples are take-off distance (longer) and cruise Mach number (slower). The best Box Wing Aircraft (BWA) configuration may be a rather conventional one with tail aft and a wing configuration similar to a biplane but with wing sweep as required for cruise Mach number. The proposed configuration is the "Smart Turboprop" especially combined with a braced wing and partial natural laminar flow on the wing. This aircraft configuration offers substantial fuel savings and DOC improvements.
Bundesministerium für Forschung, Technologie und Raumfahrt