Vertical Tail Research Articles

Безплазовий метод конструкторської підготовки виробництва літаків авіації загального призначення

The article’s subject is the design preparation for producing light general aviation aircraft. This article aims to develop design solutions for a light cheap aircraft with low flight and ground costs, to substantiate the possibility and necessity of using modern CAD systems and new plazless methods to ensure the interchangeability of light aircraft components to reduce design and production costs. Objective: to analyze the global demand for light aircraft, to substantiate the possibility and feasibility of introducing independent (plazless) methods for linking technological equipment and aircraft design components, to develop a list of design work and expected results, to develop digital models (electronic drawings) of the aircraft as a whole and its components, to prove the effectiveness of such approaches. The research methods used are the analysis of scientific and technical documentation, numerical modeling of the aerodynamic flow around the aircraft, the stress-strain state of the units, and the design of the aircraft and its components considering the results of numerical modeling. The following results were obtained: a set of digital models (electronic drawings) of the whole aircraft, a fuselage, a wing, a horizontal and vertical tail, a chassis, digital models (electronic drawings) of the aircraft parts. The scientific and practical novelty of the obtained results is as follows: a set of aircraft design engineering documents developed based on statistical data analysis and numerical modeling will allow manufacturing, testing the aircraft, and obtaining a certificate of airworthiness, which, in turn, will make it possible to subsequently begin serial production of the aircraft and create full-fledged primary flight training classes designed to improve flight training activities for cadets of higher military educational institutions and create opportunities for training civilian pilots.

Numerical Study of Flow Control to Increase Vertical Tail Effectiveness of an Aircraft by Tangential Blowing

Numerical Study of Flow Control to Increase Vertical Tail Effectiveness of an Aircraft by Tangential Blowing

A Hinge Moment Alleviation Control Strategy for Morphing Tail Aircraft Based on a Data-Driven Method

Morphing airplane technology is currently a focal point of research. For morphing airplanes, besides effective morphing strategies and control schemes, the hinge moment at the root of the vertical tail during morphing is a critical factor influencing flight safety. To prevent failure in tail morphing due to excessive hinge moments, this paper analyzes the hinge moment characteristics of the variable vertical tail structure in high-speed flight, based on a flying wing model from the China Aerodynamics Research and Development Center. The proposed adaptive morphing tail hinge moment reduction (AMTHR) method is model-free, utilizing real-time data to dynamically adjust the rudder and reduce hinge moments without requiring prior knowledge of system dynamics. This method utilizes the concept of extremum-seeking control by introducing periodic perturbations to the system and adjusting the control input based on their impact on the output. This approach drives the output toward an extremum point, enabling real-time reduction of the vertical tail hinge moment. Finally, the simulation analysis is carried out under the conditions of no wind and gust disturbance, and the effect of this method on the load reduction of the tail hinge moment is verified.

Numerical simulation and optimization of gas premixing structures for tail gas incinerators

It is a common practice for chemical refinery tail gases to be treated in an incinerator and then released into the atmosphere. However, tail gas combustion is a key component in ensuring that the treatment process meets the relevant standards. In this paper, a vertical tail gas incinerator gas premixing structure design is proposed, aiming to improve the gas mixing effect. Based on the basic structure of the right-hand gas distribution pipe and the single-layer fan mixer at the throat, three new structures are proposed. The five new gas-premixing structures were combined into eight new structures. A series of numerical simulations were performed for one prototype premixed structure and five new premixed structures, respectively. The gas premixing structures were screened, evaluated, and optimized using gas mixing inhomogeneity and pressure loss as control parameters. Finally, the premixing structure with the best combination for the mixing unit was selected. This study is of great significance for improving the effectiveness of tail gas incineration in chemical refineries and protecting the ecological environment.

UAV Wing leading edge crashworthiness behaviour under bird strike events: The added value of CF/PA additive solutions versus traditional metallic wing structures

In recent years, an increasing interest in innovative solutions design of aircraft structural components has been raised through both research and industrial fields, aimed at optimising weight and enhancing the ability to withstand both static and dynamic loads. This study compares the structural response to a bird strike phenomenon of a vertical tail of a UAV in standard metallic configuration with the one obtained from an innovative solution, equal in volume but with an internally designed architecture for an additive approach and manufactured by employing a carbon fibre reinforced filament engineered for metal replacement applications (carbon fibre, CF/polyamide, PA). The additive solution proposes the use of a 10 % infill and a lattice structure that completely replaces the traditional aircraft structure concept. This approach leads to a significant weight reduction, approximately 45 % compared to the traditional metallic configuration. The investigation was conducted through explicit numerical simulations considering different impact angles. The numerical model of the bird strike has been assessed by numerical-experimental comparison, simulating the impact of a bird with a flat plate. For this study, the Coupled Eulerian-Lagrangian (CEL) approach has been adopted to perform the simulation. The results were compared in terms of stress distribution, failure analysis, displacements, and energy-time and force-time diagrams. The work demonstrated that using innovative manufacturing processes, such as additive manufacturing, can significantly improve the bird strike resistance of aerospace structures. This improvement is achieved though the production of lighter, structurally collaborative geometries, by reducing the load transferred to the rest of the UAV by about 47 % and decreasing the displacement on the impact area by 53 %.

Research on torque measurement in flight test for all-moving horizontal tail based on spiral driver

PurposeTorque is one of the main loads acting on the aircraft wing, the horizontal tail and the vertical tail. In flight load measurement, due to the significant influence of the bending moment and the shear force on the strain gauge, the accuracy of torque measurement is usually low. Therefore, aircraft torque measurement is difficult. Based on the characteristics of a certain type of horizontal tail, a measurement method for the torque with high accuracy was proposed in this paper.Design/methodology/approachA new simplified torque measurement method for the all-moving horizontal tail was proposed based on the spiral driver. The feasibility of the method and key points of the tests were analyzed and studied through a virtual load calibration test.FindingsBased on the results of the real load calibration test, the torque load equation with high accuracy was established, and the torque measurement was achieved in load flight tests.Research limitations/implicationsHowever, the proposed method is based on the structure of the spiral driver. If there is generally no spiral driver at the aircraft wings and vertical tails, then the appropriate torque measurement method needs to be derived according to the specific object.Originality/valueThe research in this paper provides a new idea for the torque measurement of aircraft structures, which can be used for the torque measurement of subsequent aircraft types.

Structural Evaluation of a Vertical Tail for a Supersonic Vehicle: Architecture, Boundary Conditions, and Material System Influence

Structural Evaluation of a Vertical Tail for a Supersonic Vehicle: Architecture, Boundary Conditions, and Material System Influence

Metal Replacement in UAV Vertical Tails Using Additive Manufacturing

Metal Replacement in UAV Vertical Tails Using Additive Manufacturing

An innovative approach to a UAV tails structural design for additive manufacturing

AbstractThe innovative approach used for the design and fabrication of a UAV tails through additive manufacturing (AM) completely changes the concept of designing and manufacturing products through conventional methods. AM based processes can reduces costs, lead times, and increases design freedom, allowing parts to be tailored to specific needs. A key benefit of AM processes is the ability to produce optimized designs with reduced mass and without compromising structural effectiveness. This is possible thanks to the combination of high‐performance AM materials and the extraordinary manufacturing capability of AM technologies combined with an appropriate design‐for‐additive manufacturing (DfAM) approach, overcoming traditional manufacturing techniques. This article presents the development process of a UAV tails, based on a Design for Additive Manufacturing (DfAM) approach in order to reduce structural mass and guarantee safe operation under service loads. Therefore, by replacing the metallic component of the UAV with a techno‐polymeric one, several configurations have been developed. The optimal additive configuration achieved a weight reduction of 60% compared to a metal configuration of equivalent volume, without loss of mechanical properties. In conclusion, a feasibility study of the proposed configuration was carried out by 3D printing the vertical tail redesigned.Highlights An innovative approach by combining DfAM processes with FFF technology. Metal replacement of UAV tails with advanced technopolymers. Efficient Weight Reduction about 60% compared to metal structure. Single‐piece design simplifies assembly and manufacturing. UAV redesigned tails with enhanced efficiency, adaptability, and feasibility.

Simulation experiment on support strength of aircraft structural components

The design principles of strength test support methods for aircraft structural components were introduced in this paper. Aiming at the vertical tail static test of a certain type of aircraft, a supporting stiffness simulation method was invented, and a support fixture was designed. The supporting stiffness was accurately simulated by stiffness strength. The research results of this paper provide an important reference for the research of static test support methods for similar aircraft structural components.

Coupled funnel control for supersonic tailless aerial vehicle on penetrating counter air

Supersonic Tailless Aerial Vehicles (STAVs) will become an essential force in Penetrating Counter Air (PCA), but STAVs do not have the traditional horizontal and vertical tails, making pitch and yaw control difficult. The attack angle and the sideslip angle need to be limited to ensure that the engine inlet and the aerodynamic rudder at the rear of the vehicle can work properly, which is the so-called security constraints. In addition, the tracking error of the aerodynamic angle needs to be limited to achieve effective attitude control or high-accuracy tracking of trajectories, which is the so-called performance constraints. To this end, an attitude control method that meets the needs of PCA has been devised, based on constraint definition, coupled constraints handling, and control law design. Firstly, mathematical descriptions of the security constraints, performance constraints, and control constraints are given. Secondly, two treatment methods, coupled command filter and coupled funnel control are proposed for the aerodynamic angle coupled constraint problem. Finally, based on Nonlinear Dynamic Inverse (NDI) design, the coupled funnel controller is designed and validated by simulation for two typical mission scenarios, high-altitude penetration and low-altitude surprise defence. The proposed control method not only satisfies the security and performance constraints of STAV attitude control but also is highly robust.

Determination of the features of integrated design of civil long-range aircraft with transonic truss-braced wing at the preliminary design stage

The object of research is a civil mainline aircraft with a transonic truss-braced wing. The problem of designing an aircraft of this scheme at the preliminary design stage is being solved in the work. The results of the work include the concept of designing aircraft with a transonic truss-braced wing, the main advantages of such a scheme, the process of determining the geometric parameters of the truss-braced, features of the preliminary design of an aircraft with an extremely high aspect ratio truss-braced wing, possible approaches to the arrangement of units and their mutual arrangement. The results are explained by the difference in the design model (the cantilever beam is replaced by a beam on two supports) in mass analysis and the increased wing aspect ratio in aerodynamic calculation. The final data are based on a statistical study to determine the basic geometric parameters of assemblies of modern mainline passenger aircraft, synthesis of parameters of analog aircraft. For example, an aircraft capable of carrying 250 passengers over a distance of 13.000 km is considered. In the design process, values of aspect ratio, taper ratio, wing area, vertical tail and horizontal tail area ratio, and fuselage dimensions are accepted. Drawings of the general appearance of the aircraft have been developed and, based on it, a master geometry of the theoretical contour has been constructed. Graphs of first-order polar and maximum lift-to-drag ratio have been plotted, the reduction of aerodynamic drag in percentage terms has been determined, and the increase in aerodynamic lift-to-drag ratio in percentage terms for an aircraft with an extremely high aspect ratio truss-braced wing compared to similar characteristics of an aircraft with a conventional non-braced wing has been calculated. The approximate mass savings when using a truss-braced wing on the aircraft are determined in percentage terms. The expediency of using wings of greater aspect ratio, than modern aircraft currently have, has been justified. The expediency of using a brace for the aircraft with an extremely high aspect ratio wing has been justified. The obtained results can be used in practice in the process of developing the preliminary design of an aircraft with a truss-braced wing or in the modifications of existing aircraft to increase their fuel efficiency or increase the durability of wing elements due to reduced loads acting on them.

On the effect of printing orientation on the surface roughness of an additive manufactured composite vertical tail

On the effect of printing orientation on the surface roughness of an additive manufactured composite vertical tail

Integrated design of lateral-directional control law and vertical tail load for civil aircraft

According to new requirements of airworthiness regulation CS25.353, the advanced lateral-directional P-Beta control law design is studied in this paper. The LQR method based on the tracking command model is used to design the lateral-directional control law parameters. At the same time, the vertical tail load model of aircraft for yaw maneuver is introduced into the lateral-directional control law design model. The aim is to build the integrated design of control law and flight load. Finally, the simulation results show that the P-Beta control law can not only improve Dutch roll damping and coordination turn characteristics, but it can also reduce the yaw maneuver load by 18.5%. Thus, the structure weight of the aircraft’s vertical tail can be reduced.

Field Quality Improvement of Septum Magnets for SuperKEKB Injection System

The SuperKEKB accelerator is a electron-positron collider consisting of the 7 GeV electron ring (high energy ring or HER) and the 4 GeV positron ring (low energy ring or LER). The commissioning of the SuperKEKB accelerator is underway, aiming to supply a great number of interaction events of electrons and positrons to the Belle II detector which is used for discovering the new physics beyond the standard model. The important milestone is to obtain integrated luminosity of 15 ab–1 in the next decade, so that the luminosity should exceed 2 × 1035 cm–2s–1 in several years. To achieve the goal, both rings have to be filled with high current beam of a few amperes, where the high injection efficiency is vitally important because lifetime is expected to be very short. One of the key components of the injection system is the septum magnet. It has been found that a transverse fringe field near the septum plate has sizable multipole components. A tracking simulation shows such fringe fields generate a vertical non-Gaussian tail, which could cause a beam background as well as a bad injection efficiency. Though quadrupole component in the multipoles could be, in principle, cancelled by adjusting the quadrupole magnets in the upstream of the beam line, it turned out to be difficult in actual operation. Even the quadrupole component was perfectly cancelled, components higher than quadrupole would be still harmful, since it generates a beam halo in the ring after injection, which increases the beam backgrounds to the Belle II detector. This paper describes about improvement of the field quality of the septum magnet.

Three-Dimensional Quantitative Flow Visualization Around a Thrust Reverser

Volumetric particle tracking velocimetry measurements are performed in a low-speed wind tunnel to study the flow around a 1:12-scale aircraft model with jet engines operating with thrust reversers. The engine jet and freestream flow velocity are varied to yield a jet to freestream velocity ratio of ranging from 1.5 to 6. Measurements at such scale () require the use of strongly scattering helium-filled soap bubbles as flow tracers, which are introduced in both the jet and the freestream flow. The tracer’s three-dimensional motion is determined using an array of cameras and a Lagrangian particle tracking algorithm. The mean velocity field reveals the jet inner structure as well as its interaction with the freestream, the ground board, the nacelle, the fuselage, and the horizontal and vertical tails. The experiments allow detection of exhaust reingestion as well as the aerodynamic interference with control surfaces at the tail segments in a single measurement volume. The results are in good agreement with conventional temperature rake measurements while adding details of the flow topology and of the large-scale unsteady flow fluctuations. Finally, the jet reversal characteristics with varying freestreams and nozzle pressure ratios are assessed, demonstrating the feasibility and versatility of volumetric velocimetry measurements for industrial aerodynamics.

Why Birds and Airplanes Need No Vertical Tail

The question of why airplanes need a vertical tail whereas birds seem to do very well without one has been longstanding. Some have suggested that it is a matter of scale; that the rationale for a vertical tail disappears when coming down the scale from the regime of "full" scale aircraft to bird/ small scale flight regime. This hypothesis has now been debunked. This paper shows that the lateral-directional modal dynamics and stability criteria remain unchanged over the relevant range of flight Reynolds numbers. It conclusively establishes that a vertical tail is not essential for directional or lateral stability at any scale from that of bird flight to "full" scale airplane flight.

Analysis of Aerodynamic Characteristics of Different Tail Configurations of Compound High-speed Helicopters

When a compound high-speed helicopter is in forward flight, there are serious aerodynamic disturbances among the fuselage components, among which the tail configuration has a greater influence on its aerodynamic performance. To study the influence of different tail configurations on aerodynamic performance, the flow field of a compound high-speed helicopter in forward flight was numerically simulated based on the commercial software XFlow. Firstly, the ROBIN standard helicopter fuselage model was calculated to verify the scientific validity of the method. Then, the aerodynamic data of a high-speed helicopter was analyzed for different tail configurations in forward flight with different angles of attack and yaw. The results show that the V-tail configuration has the lowest lift and resistance coefficients and the best longitudinal manoeuvrability and stall characteristics; the conventional tail configuration has the highest lift-to-resistance ratio and the fastest wake decay; the lateral stability of the V-tail and conventional tail configurations is weaker than that of the H-tail and fixed tail configurations; and the presence of the vertical tail in the tail increases the pressure value around the wing surface.

Validation of Paras3d Rans Pressure Data with Flight Results Over a Wing-body Rlv Configuration at Supersonic High Angle of Attack Conditions

Winged Reusable Launch Vehicle - Technology Demonstrator (RLV-TD) was successfully flight tested by Indian Space Research Organisation (ISRO). One of the main objectives of this Hypersonic Experiment (HEX) mission is to validate the aerodynamic design and ground based aerodynamic data generation procedure. In this paper, comparison of flight data and CFD estimated pressure coefficient (Cp) over fuselage, wing, vertical tail and rudder are presented at supersonic Mach number and high angle of attack conditions. PARAS3D RANS solver is able to capture the trends as measured in flight. In general, PARAS3D CFD over predicted the compression on windward side and under predicted leeward expansion as compared to flight measurement. In general, CFD predicts Cp close to flight measured value, except over a port in the vertical tail.

Some Morphofunctional Features of the Tail of Early Archosaurs in Relation to Swimming Adaptation

In ancient and modern aquatic and semi-aquatic tetrapods, several types of structure of the locomotor apparatus are presented, providing various styles of swimming. In the course of evolutionary adaptation to swimming, an important role was played by the morphological transformations of the tail, which often performs the main propulsion function. Modern reptiles (except turtles) swim mainly with the help of horizontal tail bends, while mammals swim either vertical or horizontal ones. Among extinct reptiles, Sauropterygia probably used vertical tail mobility when swimming. In most archosauromorphs, the tail became high, laterally compressed, and they swam mainly with the help of its horizontal movements. Among early archosaurs, Proterohampsians and Doswelliids are distinguished by their wide and dorsoventrally flat tails, which may indicate an adaptation to swimming using its vertical mobility.