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Formation flying techniques, demonstrated by migratory birds, have the potential to significantly save energy when two or more transport aircraft fly the same route at the same time. In fuel-saving...

Tiltrotor aircraft ship suitability and envelope expansion testing aboard a U.S. Navy aircraft carrier is discussed. The purpose was to validate and expand day/night vertical launch and recovery wi...

This paper analyzes the effects of the helicopter dynamics on pilots’ learning process and transfer of learned skills during autorotation training. A quasi-transfer-of-training experiment was performed with 14 experienced helicopter pilots in a moving-base flight simulator. Two types of helicopter dynamics, characterized by a different autorotative index, were considered: “hard,” with high pilot compensation required, and “easy,” with low compensation required. Two groups of pilots tested the two types of dynamics in a different training sequence: hard-easy-hard (HEH group) and easy-hard-easy (EHE group). Participants of both groups were able to attain adequate performance at touchdown in most of the landings with both types of dynamics. However, a clear positive transfer effect in terms of acquired skills is found in both groups from the hard to the easy dynamics, but not from the easy to the hard dynamics, confirming previous experimental evidence. Positive transfer is especially observed for the rate of descent at touchdown. The two groups differed in the control strategy applied, with the HEH group having developed a more robust control technique. During the last training phase the EHE group aligned its control strategy with that of the HEH group.

Compared to other information sources, motion cues provide a pilot with anticipatory information about spatial position and movement of aircraft. For motion cueing a flight simulator cockpit is installed on a motion system, movement of which motion cueing. Therefore, motion system is one of the most important components of full flight simulators. The problem of effective use of constructive resources of six-degrees of freedom synergistic motion system has been solved. But the problem of improving the motion cueing re- mained unsolved, due to the fact that location of motion system center of rotation is significantly different from location of aircraf’s center of gravity, and motion cues differ from real, flight one. The study subject is motion cueing on flight simulators. The problem was solved on the basis of simplified operator for transformation of motion system movements along individual degrees of freedom into jack movements, cubic spline functions to describe the dependence of the centers of rotation along pitch and yaw, and optimization theory using the deformable polyhedron method. The formulated and solved problem of taking into account of location of aircraft’s center of gravity during motion cueing along pitch and yaw increases an efficiency of using of constructive resource of a six-degrees of freedom synergistic motion system, a motion cueing fidelity and training realism on flight simulator. Порівняно з іншими джерелами інформації акселераційні впливи забезпечують пілота випереджальною інформацією про просторове положення і рух літака. Для імітації акселераційних впливів кабіна тренажера встановлюється на динамічному стенді, переміщення якого імітують акселераційні впливи. Тому динамічний стенд є одним з найважливіших складових комплексних тренажерів літаків. Вирішена проблема ефективного використання конструктивних ресурсів шестистепеневих динамічних стендів опорного типу. Але не вирішеною залишалася проблема поліпшення імітації акселераційних впливів, обумовлена тим, що розташування центра обертання динамічного стенда суттєво відрізняється від розташування центра мас літака, а імітовані акселераційні впливи відрізняються від реальних, польотних. Предметом дослідження є імітація акселераційних впливів на авіаційних тренажерах. Проблема розв’язувалась на засадах спрощеного оператора перетворення переміщень динамічного стенду за окремими степенями вільності в переміщення силових гідроприводів, використання кубічних сплайн-функцій для опису залежностей центрів обертання за тангажем і рисканням та теорії оптимізації з використанням методу деформовного багатогранника. Сформульована і розв’язана задача врахування розташування центра мас літака через наближення центрів обертання динамічного стенду до центра мас літака при імітації акселераційних впливів за тангажем і рисканням підвищує ефективність використання конструктивного ресурсу шестистепеневого динамічного стенду опорного типу, якість імітації акселераційних впливів та реалістичність навчання на авіаційному тренажері.

Distributed simulations require efficient communication to represent complex scenarios, which presents a great challenge. This paper investigates the use of message-oriented middleware (MOM) to address this challenge by integrating the flight simulator X-Plane with the tactical simulator TACSI and evaluating the performance of different data transfer approaches. The study assesses performance by measuring the maximum sustainable throughput (MST) and the latency of a publish-subscribe-based MOM system. Two data distribution methods are compared: single-topic publishing and publishing to multiple subtopics. The results show that single-topic publishing achieves higher MST and lower latency when transmitting the same data volume. These findings provide valuable insights for deciding the state distribution method for publish-subscribe MOM systems. Additionally, this study highlights the limitations of manual determination of MST and underlines the need for accurate performance measurement techniques. Distribuerade system kräver effektiv kommunikation för att representera komplexa scenarion, vilket utgör en betydande utmaning. Denna rapport använder meddelandeorienterad mellanprogramvara (MOM) för att angripa denna utmaning genom att integrera flygsimulatorn X-Plane med den taktiska simulatorn TACSI och sedan utvärdera prestandan av olika dataöverföringsmetoder. Studien utvärderar prestandan genom att mäta den maximala genomströmningskapaciteten och latensen på ett publish-subscribe-baserat MOM-system. Två dataöverföringsmetoder jämförs: single-topic publicering och publicering på flera subtopics. Resultatet visar att single-topic publicering ger högre maximal genomströmningskapacitet och lägre latens vid samma mängd data. Dessa upptäckter ger värdefulla insikter när man ska bestämma metod för dataöverföring i publish-subscribe-baserade MOM-system. Slutligen visar denna studie på begränsningarna med att manuellt bestämma MST och behovet av mer noggranna tekniker för att mäta maximal genomströmningskapacitet.

This paper presents a tilt-rotor flight simulation platform implementing a real-time simulation of the Bell XV-15 aircraft for teaching and research purposes. The mathematical model of the tilt-rotor aircraft is implemented in MATLAB/Simulink© including simplified models of aircraft dynamics, actuators, sensors, and Flight Control Computer. The implemented tilt-rotor mathematical model is interfaced with flight control hardware, i.e. a flight stick and a rudder pedal, used by the pilot to set input commands. Instead, the graphics environment is provided by FlightGear, an open-source and cross-platform software widely used in research activities. Another contribution of the paper is the design and implementation of a Stability Control and Augmentation System to enhance aircraft stability and improve handling qualities. The developed simulator is tested with several simulations validating the developed mathematical model and the effectiveness of the Stability Control and Augmentation System. The result is a tilt-rotor flight simulation platform executable on a commercial laptop with real-time performance for research and teaching activities.

Flight simulators have been used for a long time to train pilots of any type of aircraft. This type of training is more economical. The flight simulator improves control skills in extreme situations with minimal risks for the future pilot. Training on a flight simulator makes it possible to reproduce adverse weather conditions at any time. The pilot is on the ground in a special cockpit, which is mounted on a movable platform. This system is needed to ensure flight conditions as close to real as possible. The subject of the research in the article is an aviation simulator on the Stewart platform. The aim is to create and analyze an flight simulator platform using software. The paper presents the already existing flight simulator and its characteristics. Taking into account its dimensions and weight, the platform is modeled in SolidWorks. The kinematic diagram of the type design (6-6) is selected and presented. The basic equation of dynamics for calculating platform motion law for given values of the control forces is given. Also using this equation it is possible to find the controlling forces knowing the law of motion. The developed 3D model consists of two platforms, a movable and a stationary one. The legs with automatically variable length are attached to the platform using hinges. Selected material aluminum alloy type 2024 from which the platform is created. Selected material aluminum alloy type 2024 from which the platform is created. Static analysis of the loaded platform was performed. By loaded platform is meant that in the places where the simulator and the pi-lot's seat are installed, loads equal in weight to the simulator and the maximum weight of the seat with the pilot are applied. The anal-ysis includes such epurfaces: loads to assess whether the structure can support a given weight, displacement, deformation, safety margins and a Design Insight plot to evaluate design details. Identification of elements that are most likely to start collapsing under the weight of the simulator. The research was performed using SolidWorks Simulation software. Based on the data obtained from the plot, conclusions were made about the performance and safety of the developed platform.

The use of finite-state methods is critical to the development of accurate and efficient inflow models used in rotorcraft flight dynamics simulation and control. Recent work in the finite-state fie...

A small collapsible common-axis dual-rotor drone has been designed independently by performance indicators. The model was computed through three-dimensional modeling and meshing. Using Fluent software, the wind tunnel test simulation of the blades was obtained, and the results of the blade model test were compared with the results of the blade model. The lift data of CFD at different speeds were consistent with the results of the paddle model test, with a maximum error of only 12.46%. Using the mesh Boltzmann method (LBM) based on smooth particle theory, the non-normal aerodynamic strain of the most severe conditions in the flat flight is selected for modeling analysis. The aerodynamic layout design of a type of coaxial twin-rotor aircraft and its nonlinear six-degree-of-freedom flight simulation modeling and control system were verified. The results show that the design of the common-axis twin-rotor aircraft can meet the higher aerodynamic index requirements. The control performance and wind disturbance resistance of the designed aircraft are tested and verified by the flight simulation of Matlab/Simulink, and the simulation results show that the system can achieve the desired control goal by adding the closed-loop altitude controller and speed controller. It also provide a basis for further study of its aerodynamic properties.

Flying and driving simulation has encouraged an enormous and growing community in a wide variety of areas such as research centers, driver or pilot training academies, vehicle-testing facilities, amusement parks, and even at home by household enthusiasts, providing carefully integrated visual and perceptual illusions of driving or flying real vehicles. The global research on this subject is explored during the period 2000 to 2019 from an interdisciplinary perspective based on a systematic methodology, providing both new and experienced researchers with broad guidance toward key aspects for further investigations and developments. Emphasis is given to the analysis of the findings and in particular to their applicability, to an extent not attempted earlier, by considering both human and machine aspects.

The Design of the flight simulator mechanism is an essential link in the development of aviation technology. The six-degree-of-freedom Stewart parallel mechanism is used as the mechanical body of most traditional flight simulators. They can simulate the six-degree-of-freedom motion of the aircraft. However, the reachable attitude of the moving platform of the Stewart parallel mechanism is relatively small, and its range of motion is ± 35°, which can only achieve a small range of yaw, roll and pitch. It can only satisfy the simulation of the attitude change of a civil aviation aircraft. A 4PUS-PPPS redundant parallel mechanism equipped with visual function is proposed to simulate the high motion performance of fighter aircraft, which can realize the movement of angles (− 90°,178°) around the horizontal axis of the aircraft. The flight attitude data of the aircraft were acquired and processed by filtering algorithms in the software of Unity 3D environment. Then, the three steering gears that simulate the action of the moving platform are controlled by the processed data, which realizes the simulation control of the combination of virtual and honest and provides a new idea for the research of redundant parallel mechanisms.

The paper deals with the problem of estimating the projections of the wind velocity in flight. The proposed method allows to obtain estimates for three projections of wind speed in the normal Earth coordinate system using data from the satellite navigation system, as well as on-board aerometric measurements of airspeed, angles of attack and glide. The main idea underlying the method is that satellite measurements of three aircraft velocity projections relative to the Earth’s coordinate system are very accurate (errors usually do not exceed 0.2 m/s). This makes it possible to use satellite velocity measurements as a kind of reference, just as in practical metrology, in order to assess the errors of measurement tools, they are compared with a standard, that is, a significantly more accurate measurement tool. In order to implement this approach not in a metrological laboratory, but on board an aircraft, it is proposed to use the relationships known from the flight dynamics between the velocity projections in the Earth’s and associated coordinate systems, the angles of attack and glide, and the wind speed. Then, the three wind speed projections are assigned unknown parameters, which are found using parameter identification. It is assumed that the wind has a constant speed and direction in the processed section of the flight. The accuracy characteristics of the proposed algorithm were evaluated based on the data obtained on the flight simulator of a modern training aircraft. In the course of simulation, random measurement errors were generated at the levels corresponding to the flight experiment. The influence of the type of maneuvers on the accuracy the three wind speed projections estimates was also studied. It is shown that for all considered maneuvers, that is "barrel", "snake", stepwise inputs, the errors in estimating the horizontal components of wind speed generally do not exceed 5 %, the vertical component 10 %, with the duration of the sliding processing interval of 0.5 and 1.0 s, which allows not only to estimate the constant wind speed, but also to track its change.

Avionics is a category of electronic systems, equipment and instruments specifically designed for use in aviation. Usually called autopilot, the Automatic Flight Control System, is one of the main systems in avionics. Autopilot systems are designed to automatically control the aircraft piloting, reducing the pilot fatigue caused by the flight. Before being embedded into an aircraft, an autopilot system must be exhaustively evaluated by computational simulations to be validated. The objective of this work is to describe the development of an embedded automatic flight controller aimed to be applied to a Cessna-172SP-Skyhawkmodel aircraft in order to control its altitude. The developed flight controller is based on a tuned PID control and it is embedded in a Raspberry Pi that actually controls the altitude of the aircraft simulated in the X-Plane 11 flight simulator, running on a Desktop PC connected by UDP to the Raspberry Pi. The simulation results validated the proposed flight controller as well as the proposed hardware scheme for validation.

In this article, the results of a piloted flight simulator campaign aimed at measuring biomechanical performance indicators of a helicopter pilot performing complex, realistic tasks are presented. The upper limbs’ motion and the activation of the main muscle groups of the left arm were measured during ship-deck landings, performed flying several helicopter configurations with sea conditions of variable intensity. The analysis of the results shows an increase in the muscle activity relative to the increase in task difficulty, in agreement with subjective ratings (Bedford workload scale). The study provides useful indications to improve the corresponding biomechanical simulations, as well as to characterize pilot's performance during specific tasks.

To achieve system resilience, one can leverage high-level design features (e.g., redundancies and fail-safes), adjust operational profiles (e.g., load or trajectory), and use appropriate contingenc...

The article presents an innovative approach to the description of the aircraft range parameter in discrete time when simulating the process of its repositioning in space. A method of describing the dynamics of changes in signal delay in discrete time when the aircraft is changing its spatial position is proposed. Such a model adequately describes the change in signal delay in discrete time. The direction of estimation for the adequacy of radio signal delay change simulation in algorithms of optimum filtration is defined in accordance with the aerodynamic properties of the aircraft. Simulation of the signal delay dynamic change is carried out (it is completely described by the dynamics of change in the distance to the aircraft). The transformation stages of simulation data for the initial model in continuous time with realization of the standard Gaussian random numbers are justified. Information on the simulation data transformation taking into account the correlation matrix of discrete white noise is provided. A method of calculating the transition matrix through the Laplace transform is proposed. The scientific-applied direction of research is determined – it lies in the development of a method for the legitimate representation for the mathematical model of aircraft’s changing range in discrete time within one-dimensional space: the longitudinal and the transverse dimensions. This approach takes into account the continuous description for a system of stochastic differential equations. A comprehensive algorithm for modeling the values of discrete white noise on modern computer equipment and calculating the dynamics of the aircraft range parameter changes is proposed. This algorithm allows to correctly form the a priori information about the change of the vector parameters of the aircraft spatial position at discrete moments of time. As a result, it was shown that the use of the obtained information in the optimal filtering algorithms minimizes the error when determining distance to the aircraft and, accordingly, allows to increase the accuracy and adequacy of the signal delay simulation in discrete time. The results of this research can be used in modernization of the existing models and development of promising on-board radar stations, integrated rangefinders, systems of radio technical reconnaissance and electronic warfare systems, as well as in technical implementation of aircraft flight simulation systems.

Boundary Avoidance Tracking (BAT) theory has emerged as a novel theory in the area of Handling Qualities (HQ). The HQ of the aircraft in a given environment greatly influences the cognitive load of the pilot. Advancement in eye gaze tracking technologies has enabled non-invasive estimation of cognitive load of pilots, even in combat aircraft cockpits. This research is aimed to investigate BAT theory using a COTS-based eye gaze tracker to record ocular parameters like fixations and saccades to study the effects of boundary size/limits on the cognitive load of the pilot. The statistical model involved three independent variables, namely aircraft flying qualities, secondary task, and boundary size. Initially, experiments were conducted in two stages on a fixed-base variable-stability HQ research flight simulator. Further, the study was extended to inflight tests involving flights in Hawk and Jaguar aircraft maneuvering in high G conditions and undertaking various training combat missions. Both studies found statistically significant correlation between boundary size/limit and ocular parameters, in particular, the rate of fixations. The results proved the application and effectiveness BAT theory in HQ Stress Testing to elevate pilot gain, during flight testing of flight control system for a new aircraft program.

Simulating an aircraft model using of high fidelity models of subsystems for its primary and secondary flight control actuators requires measuring or estimating aero-load data acting on flight control surfaces. One solution would be to incorporate the data recorded from flight tests, which is a time-consuming and costly process. This paper proposes another solution based on the validation of an aero-loads estimator or on the hinge moments predictor for fully electrical aircraft simulator benchmark. This estimator is based on an aerodynamic coefficient calculation methodology, inspired by Roskam’s method that uses the geometrical data of the wing and control surfaces airfoils. The hinge moment values are found from two-dimensional lookup tables where the deflections of the control surfaces, aircraft altitude, and aircraft angles of attack are the input vectors of the tables; and the resulting hinge moment coefficients are the output vectors. The resulting hinge moment coefficients of the Convair 880 primary flight control surfaces are compared to those of its recorded flight test data; the results from the new software solution were found to be very accurate. Hinge moment lookup tables are integrated in the Convair 880 high fidelity flight simulation benchmark using mathematical models of energy-efficient Electro-Hydrostatic Actuators (EHA). Autopilot controls are designed for the roll, pitch, attitude and yaw damper motions using Proportional Integral (PI) controller scheduled for different flight conditions. Several different aircraft simulation scenarios are evaluated to demonstrate the efficacy and accuracy of the predicted hinge moment results.