Conceptual design of PrandtlPlane civil transport aircraft

According to aircraft manufacturers and several air transportation players, the main challenge the civil aviation will have to deal with in the future is to provide a sustainable growth strategy, in order to face the growing demand of air traffic all over the world. The sustainability requirements are related to air pollution, noise impact, airport congestion, competitiveness of the air transportation systems in terms of travel time and passengers’ comfort. Among the possible ways to allow a sustainable growth of the air transportation systems, disruptive aircraft configurations have been object of study for several years, in order to demonstrate that the improvement of aircraft performance can enable the envisaged growth. This paper presents the study of a possible novel configuration called ‘‘PrandtlPlane,’’ having a box-wing layout derived from Prandtl’s ‘‘Best Wing System’’ concept. The paper deals with the definition of top level requirements and faces the conceptual study of the overall configuration, focusing on fuselage sizing as well as on the aerodynamic design of the box-wing system. This latter is designed through an optimization-driven strategy, carried out by means of a low fidelity aerodynamic tool, which simulates the flow condition in the subsonic range and introduces correction to take the transonic effects into account. Design procedures and tools are presented, showing preliminary results related to a PrandtlPlane compliant with ICAO Aerodrome Reference Code ‘‘C’’ standard, such as Airbus A320 and Boeing 737, whose wingspan is limited to 36 m. Activities and results here shown are part of the first phase of the research project ‘‘PARSIFAL’’ (Prandtlplane ARchitecture for the Sustainable Improvement of Future AirpLanes), funded by the European Commission under the Horizon 2020 Program, which aims to demonstrate that the PrandtlPlane configuration can improve aircraft payload capability, keeping their dimensions compatible with present airport infrastructures

PRELIMINARY TAKE-OFF ANALYSIS AND SIMULATION FOR A PRANDTLPLANE COMMERCIAL AIRCRAFT

The paper describes the take-off performances and characteristics of an unconventional aircraft, called PrandtlPlane. The PrandtlPlane has a box-wing architecture, founded on the “Best Wing System” concept due to L. Prandtl, that minimizes the induced drag once wingspan and lift are given. This configuration has the potential to be a more efficient alternative to conventional tube-and-wing aircraft, and it is under investigation in the framework of the PARSIFAL project, funded by the European Union in the Horizon 2020 program. A numerical simulation tool for the take-off dynamics of the aircraft, based on the non-linear equations of motion, has been developed in order to evaluate the performance of the aircraft in take-off condition. The VLM solver has been integrated into this tool in order to evaluate the aerodynamic performance of the aircraft in ground effect at each moment of the manoeuvre. The same assessments have been made for a conventional tube-and-wing reference aircraft, with the aim of conducting a performance comparison with the reference PrandtlPlane. The preliminary results obtained show the aerodynamic and aeromechanical advantages of the reference PrandtlPlane, in terms of runway length and passenger comfort