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Aerospace
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Flight Dynamics, Control & Simulation
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Flight Dynamics, Control & Simulation

A special issue of Aerospace (ISSN 2226-4310). This special issue belongs to the section "Aeronautics".

Deadline for manuscript submissions: closed (20 October 2023) | Viewed by 35737

Special Issue Editors

Prof. Dr. Daniel Ossmann

E-Mail Website
Guest Editor
Department of Mechanical, Automotive and Aerospace Engineering, Munich University of Applied Sciences, Lothstraße 34, 80335 München, Germany
Interests: fault detection and isolation; robust control; flight control; wind turbine control
Special Issues, Collections and Topics in MDPI journals
Dr. Karim Abu Salem

E-Mail Website
Guest Editor
Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Castelfidardo, 39, 10129 Torino, TO, Italy
Interests: aircraft design; green aviation; aerodynamics; flight mechanics; innovation; multidisciplinary optimization; flight dynamics; new aircraft concepts; hybrid-electric aircraft
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The research in the field of transport aviation is constantly facing new complex and ambitious challenges. More and more, new aircraft concepts, new types of propulsion, novel techniques for aircraft control, and overall disruptive innovations are being studied, investigated, and developed. The study of flight dynamics has always been of particular relevance when it comes to investigate the behaviour of innovative transport aircraft, to assess their stability and controllability characteristics, and to evaluate their performance. Depending on the level of fidelity used, flight simulation models, methods, and tools make it possible to characterize the aeromechanical behaviour of aircraft at any stage of design process, from the initial conceptual stages to the most advanced detailed analysis. Such models are relevant to the advancements of different fields of transport aeronautics, such as the enhancement of flight safety, the optimization of mission performance, the development of new concepts for aircraft operations (e.g., urban air mobility), and the establishment of virtual certification methods. This Special Issue aims to collect as broadly as possible the most up-to-date contributions regarding the application of flight dynamics models for the characterization of transport aircraft aeromechanic features. In particular, great emphasis is placed on the development and application of simulation models aimed at analysing the performance of aircraft with a high degree of innovation, whether in terms of architecture, systems, or propulsion. In addition, the development and validation of new methodologies for aeromechanical analysis and optimization, advanced simulation, novel flight control techniques, and flight dynamics analysis tools for multidisciplinary design workflows, also represent contributions of great relevance to increase the knowledge in the field.

Prof. Dr. Daniel Ossmann
Dr. Karim Abu Salem
Guest Editors

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Aerospace is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • flight dynamics
  • performance analysis
  • flight simulation
  • advanced controls
  • new aircraft concepts
  • innovation
  • multidisciplinary optimization
  • flight mechanics

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Related Special Issue

Published Papers (15 papers)

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Editorial

Jump to: Research

6 pages, 177 KiB  
Editorial
The Key Role of Research in Flight Dynamics, Control, and Simulation for Advancing Aeronautical Sciences
by Karim Abu Salem
Aerospace 2024, 11(9), 734; https://doi.org/10.3390/aerospace11090734 - 6 Sep 2024
Viewed by 1114
Abstract
In the evolving field of research on civil and commercial aviation, the study of flight dynamics, control, and simulation is pivotal for technological progress [...] Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)

Research

Jump to: Editorial

26 pages, 8242 KiB  
Article
Modelling and Control of an Urban Air Mobility Vehicle Subject to Empirically-Developed Urban Airflow Disturbances
by Richard G. McKercher, Fidel Khouli, Alanna S. Wall and Guy L. Larose
Aerospace 2024, 11(3), 220; https://doi.org/10.3390/aerospace11030220 - 12 Mar 2024
Cited by 4 | Viewed by 1831
Abstract
Urban air mobility is expected to play a role in improving transportation of people and goods in growing urban areas while contributing to sustainable urban growth and zero-emissions future aviation. The research presented herein computationally investigated the performance of control laws for a [...] Read more.
Urban air mobility is expected to play a role in improving transportation of people and goods in growing urban areas while contributing to sustainable urban growth and zero-emissions future aviation. The research presented herein computationally investigated the performance of control laws for a generic Urban Air Taxi (UAT) subjected to empirically-developed urban airflow disturbances. This involved developing a representative flight dynamics model of a UAT in steady level cruise flight with an inner-loop autopilot. Active Disturbance Rejection Control (ADRC) and Proportional-Integral-Derivative (PID) control laws were implemented to investigate the controlled and uncontrolled acceleration responses and compare them to the acceleration limits in ISO 2631. Using a linear flight dynamics model, ADRC demonstrated improved performance over PID control with equal initial tuning effort. PID was able to reduce passenger accelerations to unharmful, though still uncomfortable, levels while ADRC further reduced the lateral accelerations to comfortable levels. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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19 pages, 4770 KiB  
Article
RBFNN-Based Anti-Input Saturation Control for Hypersonic Vehicles
by Bangchu Zhang, Yiyong Liang, Shuitao Rao, Yu Kuang and Weiyu Zhu
Aerospace 2024, 11(2), 108; https://doi.org/10.3390/aerospace11020108 - 24 Jan 2024
Cited by 6 | Viewed by 1290
Abstract
In hypersonic flight control, characterized by challenges posed by input saturation, model parameter uncertainties, and external disturbances, this paper introduces a pioneering anti-input saturation control method based on RBFNN adaptivity. We have developed adaptive laws to enhance control system adaptability and robustness by [...] Read more.
In hypersonic flight control, characterized by challenges posed by input saturation, model parameter uncertainties, and external disturbances, this paper introduces a pioneering anti-input saturation control method based on RBFNN adaptivity. We have developed adaptive laws to enhance control system adaptability and robustness by integrating mission profiles, actuator saturation failure modes, and self-evolving neural network design. Furthermore, our approach introduces a novel anti-input saturation auxiliary system, effectively addressing input saturation constraints. This innovation ensures system stability and precise tracking, even in severe input saturation constraints. The results reveal that the system’s steady-state tracking error remains under 2% under input saturation constraints, and the convergence speed demonstrates an impressive 20% improvement. These findings underscore this research’s substantial advancement in hypersonic flight control. It may significantly enhance the controllability and performance of hypersonic vehicles in real-world scenarios. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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21 pages, 3830 KiB  
Article
Tau Theory-Based Flare Control in Autonomous Helicopter Autorotation
by Umberto Saetti, Jonathan Rogers, Mushfiqul Alam and Michael Jump
Aerospace 2024, 11(1), 33; https://doi.org/10.3390/aerospace11010033 - 29 Dec 2023
Cited by 3 | Viewed by 2127
Abstract
A novel trajectory generation and control architecture for fully autonomous autorotative flare that combines rapid path generation with model-based control is proposed. The trajectory generation component uses optical Tau theory to compute flare trajectories for both longitudinal and vertical speed. These flare trajectories [...] Read more.
A novel trajectory generation and control architecture for fully autonomous autorotative flare that combines rapid path generation with model-based control is proposed. The trajectory generation component uses optical Tau theory to compute flare trajectories for both longitudinal and vertical speed. These flare trajectories are tracked using a nonlinear dynamic inversion (NDI) control law. One convenient feature of NDI is that it inverts the plant model in its feedback linearization loop, which eliminates the need for gain scheduling. However, the plant model used for feedback linearization still needs to be scheduled with the flight condition. This key aspect is leveraged to derive a control law that is scheduled with linearized models of the rotorcraft flight dynamics obtained in steady-state autorotation, while relying on a single set of gains. Computer simulations are used to demonstrate that the NDI control law is able to successfully execute autorotative flare in the UH-60 aircraft. Autonomous flare trajectories are compared to piloted simulation data to assess similarities and discrepancies between piloted and automatic control approaches. Trade studies examine which combinations of downrange distances and altitudes at flare initiation result in successful autorotative landings. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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16 pages, 8024 KiB  
Article
High-Speed Virtual Flight Testing Platform for Performance Evaluation of Pitch Maneuvers
by Hao Li, Yuping Li, Zhongliang Zhao, Xiaobing Wang, Haiyong Yang and Shang Ma
Aerospace 2023, 10(11), 962; https://doi.org/10.3390/aerospace10110962 - 15 Nov 2023
Cited by 2 | Viewed by 1479
Abstract
To research serious nonlinear coupling problems among aerodynamics, flight mechanics, and flight control during high maneuvers, a virtual flight testing platform has been developed for a large-scale, high-speed wind tunnel, based on the real physical environment, and it can significantly mitigate risks and [...] Read more.
To research serious nonlinear coupling problems among aerodynamics, flight mechanics, and flight control during high maneuvers, a virtual flight testing platform has been developed for a large-scale, high-speed wind tunnel, based on the real physical environment, and it can significantly mitigate risks and reduce the costs of subsequent flight tests. The platform of virtual flight testing is composed of three-degrees-of-freedom model support, measuring devices for aerodynamic and motion parameters, a virtual flight control system, and a test model. It provides the ability to realistically simulate real maneuvers, investigate the coupling characteristics of unsteady aerodynamics and nonlinear flight dynamics, evaluate flight performance, and verify the flight control law. The typical test results of a pitch maneuver with open-loop and closed-loop control are presented, including a one-degree-of-freedom pitch motion and a two-degrees-of-freedom pitch and roll motion. The serious pitch and roll-coupled motion during a pitch maneuver at a high angle of attack is revealed, and the flight control law for decoupled control is successfully verified. The comparison of the test results and the flight data of a real pitch maneuver proves the reliability and capability of virtual flight testing. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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17 pages, 18844 KiB  
Article
Coordinated Control of Quadrotor Suspension Systems Based on Consistency Theory
by Xinyu Chen, Yunsheng Fan, Guofeng Wang and Dongdong Mu
Aerospace 2023, 10(11), 913; https://doi.org/10.3390/aerospace10110913 - 26 Oct 2023
Cited by 3 | Viewed by 1271
Abstract
This paper designs a cooperative control method for the multi-quadrotor suspension system based on consistency theory and realizes the cooperative formation trajectory tracking control of the multi-quadrotor suspension system by designing a consistent formation cooperative algorithm of virtual piloting and a nonlinear controller. [...] Read more.
This paper designs a cooperative control method for the multi-quadrotor suspension system based on consistency theory and realizes the cooperative formation trajectory tracking control of the multi-quadrotor suspension system by designing a consistent formation cooperative algorithm of virtual piloting and a nonlinear controller. First, a new quadrotor suspension system model is established based on the traditional quadrotor model using the Newton–Euler method. This model can accurately reflect the influence of the load on the quadrotor while obtaining the swing of the load. Then, the vertical and horizontal positions are designed separately based on the quadrotor motion characteristics, and the formation algorithm based on the virtual pilot consistency theory ensures that the final convergence of each position is consistent. An integral backstepping controller and an integral backstepping sliding mode controller are designed for quadrotor position, attitude, and load swing control to achieve accurate and fast quadrotor trajectory tracking control while reducing load swing. The stability of all the controllers is demonstrated using Lyapunov functions. Finally, a multi-quadrotor suspension system formation cooperative simulation experiment is designed to verify the designed control method. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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23 pages, 12213 KiB  
Article
Modeling and Application of Out-of-Cabin and Extra-Vehicular Dynamics of Airdrop System Based on Kane Equation
by Yi Wang and Chunxin Yang
Aerospace 2023, 10(10), 905; https://doi.org/10.3390/aerospace10100905 - 23 Oct 2023
Cited by 1 | Viewed by 1428
Abstract
The application of the Kane equation in analyzing airdrop dynamics problems is rare. The main objective of this paper is to apply the Kane equation dynamics model to the analysis of the status continuity problem during the out-of-cabin process and the line sail [...] Read more.
The application of the Kane equation in analyzing airdrop dynamics problems is rare. The main objective of this paper is to apply the Kane equation dynamics model to the analysis of the status continuity problem during the out-of-cabin process and the line sail phenomenon during the extra-vehicular process. In the out-of-cabin process, an analysis of off-aircraft security and traction ratio impact was conducted. Furthermore, the BP neural network model was trained to predict the status transition of the payload for a multiple airdrop mission. In the extra-vehicular process, the spring network method was used together with the Kane equation to analyze the form and overload of the parachute line. The modeling avoids complex equations and derivations. The results suggest significant potential applications of the Kane equation in precision airdrop missions during out-of-cabin and extra-vehicular processes without heavy reliance on experimental data. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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14 pages, 4181 KiB  
Article
Nonlinear Rigid-Elastic Coupled Modeling and Oscillation Mechanism Analysis of Rotor-Body-Slung-Load System
by Yu Tian, Luofeng Wang, Zhongliang Zhou and Renliang Chen
Aerospace 2023, 10(10), 872; https://doi.org/10.3390/aerospace10100872 - 7 Oct 2023
Cited by 2 | Viewed by 1215
Abstract
In order to reveal the mechanism of Category II rotor-body-slung-load coupled oscillation (RBSLCO) with the frequency range of 2.5~8 Hz, a novel nonlinear rigid-elastic coupled model is presented for the helicopter and slung load system (HSLS) with explicit formulation. The slung load system [...] Read more.
In order to reveal the mechanism of Category II rotor-body-slung-load coupled oscillation (RBSLCO) with the frequency range of 2.5~8 Hz, a novel nonlinear rigid-elastic coupled model is presented for the helicopter and slung load system (HSLS) with explicit formulation. The slung load system model is coupled with the current rigid-elastic coupled helicopter model, considering fuselage hook point rigid-elastic coupled movements, cable stretching, and hook point force from the slung load system. The results show that carrying the heaviest load is the vital state for Category II RBSLCO. As slung load mass ratio increases, rotor-fuselage coupling becomes stronger and the oscillation frequency shifts slightly, causing a maximum of 15% reduction in stability margin. In addition, even when the load is lightweight, another form of Category II RBSLCO may appear involving fuselage bending and cable stretching. This Category II RBSLCO behaves like the vertical bouncing but is divided into a high-frequency anti-phase oscillation and a relatively low-frequency in-phase oscillation. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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33 pages, 8401 KiB  
Article
L1 Adaptive Control Based on Dynamic Inversion for Morphing Aircraft
by Lingquan Cheng, Yiyang Li, Jiayi Yuan, Jianliang Ai and Yiqun Dong
Aerospace 2023, 10(9), 786; https://doi.org/10.3390/aerospace10090786 - 7 Sep 2023
Cited by 4 | Viewed by 1838
Abstract
Morphing aircraft are able to keep optimal performance in diverse flight conditions. However, the change in geometry always leads to challenges in the design of flight controllers. In this paper, a new method for designing a flight controller for variable-sweep morphing aircraft is [...] Read more.
Morphing aircraft are able to keep optimal performance in diverse flight conditions. However, the change in geometry always leads to challenges in the design of flight controllers. In this paper, a new method for designing a flight controller for variable-sweep morphing aircraft is presented—dynamic inversion combined with L1 adaptive control. Firstly, the dynamics of the vehicle is analyzed and a six degrees of freedom (6DOF) nonlinear dynamics model based on multibody dynamics theory is established. Secondly, nonlinear dynamic inversion (NDI) and incremental nonlinear dynamic inversion (INDI) are then employed to realize decoupling control. Thirdly, linear quadratic regulator (LQR) technique and L1 adaptive control are adopted to design the adaptive controller in order to improve robustness to uncertainties and ensure the control accuracy. Finally, extensive simulation experiments are performed, wherein the demonstrated results indicate that the proposed method overcomes the drawbacks of conventional methods and realizes an improvement in control performance. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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29 pages, 2762 KiB  
Article
Research and Performance Optimization of Jump-Takeoff in Autogyros
by Yukun Wang, Lingxi Guo, Zhiming Guo, Liaoni Wu, Fuqiang Bing, Quanwen Hu and Zonghua Sun
Aerospace 2023, 10(8), 680; https://doi.org/10.3390/aerospace10080680 - 30 Jul 2023
Cited by 1 | Viewed by 1968
Abstract
The main focus of this article is on the jump-takeoff method for autogyros. On the basis of a high-confidence autogyro model, we design a jump-takeoff simulation experiment to study and optimize jump-takeoff performance. Using a simplified version of blade element theory, we conduct [...] Read more.
The main focus of this article is on the jump-takeoff method for autogyros. On the basis of a high-confidence autogyro model, we design a jump-takeoff simulation experiment to study and optimize jump-takeoff performance. Using a simplified version of blade element theory, we conduct secondary development on the YASim dynamics library in FlightGear software and construct a highly accurate auto-rotation rotor model. The implementation of jump-takeoff requires appropriate control parameters for collective angle and pre-rotation speed. We explore the minimum collective angle condition and minimum pre-rotation speed condition to obtain the jump-takeoff envelope, and we investigate the effect of changes in control parameters within the jump envelope on jump-takeoff performance. Furthermore, we optimize the jump-takeoff performance by varying the rotor diameter and blade tip weighting. Through this study of jump-takeoff performance, we are able to determine appropriate control parameters and rotor parameters for jump-takeoff schemes, establish parameter settings for simulations of jump-takeoff tests, and thereby lay the foundation for future experimental investigations of jump-takeoff of actual autogyros. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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26 pages, 59698 KiB  
Article
Potential Propulsive and Aerodynamic Benefits of a New Aircraft Concept: A Low-Speed Experimental Study
by Pedro D. Bravo-Mosquera, Hernán D. Cerón-Muñoz and Fernando M. Catalano
Aerospace 2023, 10(7), 651; https://doi.org/10.3390/aerospace10070651 - 20 Jul 2023
Cited by 5 | Viewed by 3575
Abstract
The aerodynamic design of a new aircraft concept was investigated through subsonic wind-tunnel testing using 1:28-scale powered models. The aircraft configuration integrates a box-wing layout with engines located at the rear part of the fuselage. Measurements involved a back-to-back comparison between two aircraft [...] Read more.
The aerodynamic design of a new aircraft concept was investigated through subsonic wind-tunnel testing using 1:28-scale powered models. The aircraft configuration integrates a box-wing layout with engines located at the rear part of the fuselage. Measurements involved a back-to-back comparison between two aircraft models: a podded version whose engines were assembled on pylons and a boundary-layer ingestion (BLI) version that provided several system-level benefits. The flowfield was investigated through the power balance method and a variety of pressure flowfield and inlet flow distortion metrics. The results proved that the BLI configuration enhances the propulsive efficiency by reducing both the electrical power coefficient and the kinetic energy waste due to lower jet velocities. Furthermore, there was a reduction of the total pressure recovery due to pressure gradients inside the duct, thereby causing high distortion. Overall, this research highlights the importance of wind-tunnel testing to bring any aerodynamic technology to a sufficient level of maturity and to enable future new aircraft concepts. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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31 pages, 13420 KiB  
Article
A Simulation Framework for Aircraft Take-Off Considering Ground Effect Aerodynamics in Conceptual Design
by Karim Abu Salem, Giuseppe Palaia, Mario R. Chiarelli and Mario Bianchi
Aerospace 2023, 10(5), 459; https://doi.org/10.3390/aerospace10050459 - 15 May 2023
Cited by 11 | Viewed by 4265
Abstract
The development of novel aircraft concepts and propulsion technologies requires up-to-date physics-based methods and tools for conceptual aircraft design. In this context, a simulation model for the take-off manoeuvre is proposed in this article, to be employed in the conceptual design phase for [...] Read more.
The development of novel aircraft concepts and propulsion technologies requires up-to-date physics-based methods and tools for conceptual aircraft design. In this context, a simulation model for the take-off manoeuvre is proposed in this article, to be employed in the conceptual design phase for aircraft whether of traditional or innovative configuration. The model is capable of evaluating the longitudinal dynamics, both translational and rotational, of the aircraft considered as a rigid body, and influenced by the aerodynamic effects introduced by the presence of the ground. The ground effect, indeed, induces variations in the aerodynamic forces depending on the distance and the attitude of the lifting surfaces from the ground, which may significantly influence the aeromechanical characteristics of the aircraft during the evolution of the take-off manoeuvre. The simulation model is based on the numerical solution of the equations of the dynamics of the rigid aircraft in the longitudinal plane and integrates a vortex lattice aerodynamic solver to evaluate the aerodynamic and aeromechanical characteristics of the aircraft considering the ground effect in each time-step. The proposed approach is configuration independent, as it can model the geometry, evaluate the aerodynamics, and simulate the dynamics of aircraft with any lifting architecture; furthermore, the simulation model is fast and flexible, making it effective for the conceptual phase of aircraft design. The paper proposes the description of the take-off manoeuvre of two aircraft with different airframes: one with a conventional tube-and-wing architecture and one with a box-wing lifting system. The results proposed highlight the potential of the simulation model to detect aeromechanic and dynamic differences during the development of the manoeuvre for different aircraft configurations, and to assess the significance of considering ground effect aerodynamics. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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20 pages, 25408 KiB  
Article
Investigation of the Free-Fall Dynamic Behavior of a Rectangular Wing with Variable Center of Mass Location and Variable Moment of Inertia
by Yilin Dou, Kelei Wang, Zhou Zhou, Peter R. Thomas, Zhuang Shao and Wanshan Du
Aerospace 2023, 10(5), 458; https://doi.org/10.3390/aerospace10050458 - 15 May 2023
Cited by 2 | Viewed by 1873
Abstract
In recent years, the air-drop launch technology of near-space UAVs has attracted much attention. Between downfall from the carrier and the flight control system’s initiation, the UAV presents free-fall movement. This free-fall process is very important for the control effect of the flight [...] Read more.
In recent years, the air-drop launch technology of near-space UAVs has attracted much attention. Between downfall from the carrier and the flight control system’s initiation, the UAV presents free-fall movement. This free-fall process is very important for the control effect of the flight control system and is also crucial for the safety of the UAV and the carrier. Focus is required on two important dynamic parameters of the UAV: the moment of inertia and the center of mass position. In this paper, we used a quasi-steady model proposed by predecessors to address the flat-plate falling problem with modifications to describe the freely falling motion of the wing. Computational fluid dynamics (CFD) were used to simulate the free-fall movement of the wing with various parameters, and the wing release behavior was analyzed to check the quasi-steady model. Research shows that the movement characteristics of the falling wing are mostly reflected in the longitudinal plane, and the developed quasi-steady analytical model can more accurately describe the dynamic behavior of free-fall to some extent. By using CFD methods, we further investigated the aerodynamic performance of the free-fall wing. The results show that the wing mainly presents tumbling and fluttering motion. Changing the moment of inertia around the tumbling axis changes the tumbling frequency and the time point as the wing enters tumbling. In contrast, changing the position of the center of mass significantly changes the form of falling and makes the free-fall motion more complex. Therefore, it is necessary to carefully configure the center of mass in the UAV design process. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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24 pages, 9768 KiB  
Article
Identification of Lateral-Directional Aerodynamic Parameters for Aircraft Based on a Wind Tunnel Virtual Flight Test
by Shang Tai, Lixin Wang, Yanling Wang, Shiguang Lu, Chen Bu and Ting Yue
Aerospace 2023, 10(4), 350; https://doi.org/10.3390/aerospace10040350 - 3 Apr 2023
Cited by 3 | Viewed by 2435
Abstract
In the early stages of aircraft design, a scaled model of the aircraft is installed in a wind tunnel for dynamic semi-free flight to approximate real flight, and the test data are then used to identify the aerodynamic parameters. However, the absence of [...] Read more.
In the early stages of aircraft design, a scaled model of the aircraft is installed in a wind tunnel for dynamic semi-free flight to approximate real flight, and the test data are then used to identify the aerodynamic parameters. However, the absence of the translational motion of the test model makes its flight dynamics different from those in free flight, and the effect of this difference on parameter identification needs to be investigated. To solve this problem, a 3-DOF wind tunnel virtual flight test device is built to fix the test model on a rotating mechanism, and the model is free to rotate in three axes through the deflection of the control surfaces. The flight dynamics equations for the wind tunnel virtual flight test are established and expressed as a decoupled form of the free flight force and the influence of the test support frame force on the model’s motions through linearization. The differences between wind tunnel virtual flight and free flight are analysed to develop a model for the identification of aerodynamic parameters. The selection of the lateral-directional excitation signal and the design method of its parameters are established based on the requirements for the identifiability of the aerodynamic derivatives, and a step-by-step method for the identification of aerodynamic force and moment derivatives is established. The aerodynamic parameter identification results of a blended wing body aircraft show that the identification method proposed in this paper can obtain results with high accuracy, and the response of the modified motion model is consistent with that of the free flight motion model. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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22 pages, 9227 KiB  
Article
Mission Performance Analysis of Hybrid-Electric Regional Aircraft
by Giuseppe Palaia and Karim Abu Salem
Aerospace 2023, 10(3), 246; https://doi.org/10.3390/aerospace10030246 - 2 Mar 2023
Cited by 21 | Viewed by 5460
Abstract
This article discusses the mission performance of regional aircraft with hybrid-electric propulsion. The performance analyses are provided by mission simulations tools specifically developed for hybrid-electric aircraft flight dynamics. The hybrid-electric aircraft mission performance is assessed for the design point, identified by top level [...] Read more.
This article discusses the mission performance of regional aircraft with hybrid-electric propulsion. The performance analyses are provided by mission simulations tools specifically developed for hybrid-electric aircraft flight dynamics. The hybrid-electric aircraft mission performance is assessed for the design point, identified by top level requirements, and for off-design missions, within the whole operating envelope. This work highlights that the operating features of hybrid-electric aircraft differ from those of aircraft of the same category with conventional thermal propulsion. This assessment is processed by properly analysing the aircraft payload–range diagram, which is a very effective tool to assess the operating performance. The payload–range diagram shape of hybrid-electric aircraft can vary as multiple combinations of the masses of batteries, fuel and payload to be transported on board are possible. The trade-off in the power supply strategies of the two power sources to reduce fuel consumption or to extend the maximum flight distance is described in detail. The results show that the hybrid-electric propulsion integrated on regional aircraft can lead to benefits in terms of environmental performance, through savings in direct fuel consumption, or alternatively in operating terms, through a significant extension of the operating envelope. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation)
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