Vittorio Cipolla, Karim Abu Salem and Filippo Bachi
The present paper aims to assess the reliability and the limitations of analysing flight stability of a box-wing aircraft configuration known as PrandtlPlane by means of methods…
Abstract
Purpose
The present paper aims to assess the reliability and the limitations of analysing flight stability of a box-wing aircraft configuration known as PrandtlPlane by means of methods conceived for conventional aircraft and well known in the literature.
Design/methodology/approach
Results obtained by applying vortex lattice methods to PrandtlPlane configuration, validated previously with wind tunnel tests, are compared to the output of a “Roskam-like” method, here defined to model the PrandtlPlane features.
Findings
The comparisons have shown that the “Roskam-like” model gives accurate predictions for both the longitudinal stability margin and dihedral effect, whereas the directional stability is always overestimated.
Research limitations/implications
The method here proposed and related achievements are valid only for subsonic conditions. The poor reliability related to lateral-directional derivatives estimations may be improved implementing different models known from the literature.
Practical implications
The possibility of applying a faster method as the “Roskam-like” one here presented has two main implications: it allows to implement faster analyses in the conceptual and preliminary design of PrandtlPlane, providing also a tool for the definition of the design space in case of optimization approaches and it allows to implement a scaling procedure, to study families of PrandtlPlanes or different aircraft categories.
Social implications
This paper is part of the activities carried out during the PARSIFAL project, which aims to demonstrate that the introduction of PrandtlPlane as air transport mean can fuel consumption and noise impact, providing a sustainable answer to the growing air passenger demand envisaged for the next decades.
Originality/value
The originality of this paper lies in the attempt of adopting analysis method conceived for conventional airplanes for the analysis of a novel configuration. The value of the work is represented by the knowledge concerning experimental results and design methods on the PrandtlPlane configuration, here made available to define a new analysis tool.
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Keywords
Giuseppe Palaia, Vittorio Cipolla, Vincenzo Binante and Emanuele Rizzo
This paper aims to present a preliminary study on a disruptive vertical take-off and landing (VTOL) configuration based on the best wing system concept by L. Prandtl.
Abstract
Purpose
This paper aims to present a preliminary study on a disruptive vertical take-off and landing (VTOL) configuration based on the best wing system concept by L. Prandtl.
Design/methodology/approach
A preliminary design has been addressed from several points of views: a conceptual design has been carried out thanks to in-house optimization tool; aerodynamic performances, propulsion design and mechanical design have been addressed to make the first prototype for preliminary vertical flight tests.
Findings
The study shows the feasibility of box-wing configuration for VTOL aircraft.
Practical implications
The work shows a general design procedure for box-wing unmanned air vehicle (UAV) configuration. The study of this configuration can be easily adopted in wider range, from UAV to general aviation. In the last category, it can be a promising configuration for the future of urban air mobility.
Originality/value
This work lays the foundation for studying and testing box-wing configuration for unmanned VTOL aircraft. The design procedure can be scaled to manned aircraft belonging to general aviation aircraft.
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Pierpaolo Pergola and Vittorio Cipolla
The purpose of this paper is to deal with the study of an innovative unmanned mission to Mars, which is aimed at acquiring a great amount of detailed data related to both Mars’…
Abstract
Purpose
The purpose of this paper is to deal with the study of an innovative unmanned mission to Mars, which is aimed at acquiring a great amount of detailed data related to both Mars’ atmosphere and surface.
Design/methodology/approach
The Mars surface exploration is conceived by means of a fleet of drones flying among a set of reference points (acting also as entry capsules and charging stations) on the surface. The three key enabling technologies of the proposed mission are the use of small satellites (used in constellation with a minimum of three), the use of electric propulsion systems for the interplanetary transfer (to reduce the propellant mass fraction) and lightweight, efficient, drones designed to operate in the harsh Mars environment and with its tiny atmosphere.
Findings
The low-thrust Earth-Mars transfer is designed by means of an optimization approach resulting in a duration of slightly more than 27 months with a propellant amount of about 125 kg, which is compatible with the choice of considering a 500 kg-class spacecraft. Four candidate drone configurations have been selected as the result of a sensitivity analysis. Flight endurance, weight and drone size have been considered as the driving design parameters for the selection of the final configuration, which is characterized by six rotors, a total mass of about 6.5 kg and a flight endurance of 28 minutes. In the mission scenario proposed, the drone is assumed to be delivered on the Mars surface by means of a passive entry capsule, which acts also as a docking station and charging base. Such a capsule has been sized both in terms of mass (68 kg) and power (80 W), showing to be compatible with 500 kg-class spacecraft.
Research limitations/implications
As a general conclusion, the study shows the mission concept feasibility.
Practical implications
The concept would return incomparable scientific data and can be also be potentially implemented with a relatively low budget exploiting of the shelf components to the larger extent, small identical spacecraft buses and modular low-cost drones.
Originality/value
The innovative mission architecture proposed in this study aims at providing a complete coverage of the surface and lowest atmospheric layers. The main innovation factor of the proposed mission consists in the adoption of small multi-copter UAVs, also called “drones,” as remote-sensing platforms.