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Today, the design process of high‐lift configurations in industry mainly relies on experts' knowledge, and lacks a simple exploration of the design space. Therefore, the introduction of high‐fidelity tools in an optimization chain is now envisaged. The purpose of this paper is to define and solve a realistic high‐lift design problem by the use of a constrained evolutionary algorithm, coupled to a Navier‐Stokes (RANS) solver. The complete optimization (shape and settings) of a 3‐element configuration has been carried out for landing and take‐off configurations using a sequential approach.

In a first step, the elements' shapes and settings of the landing configuration have been optimized simultaneously. Then, shapes have been frozen and settings have been optimized for take‐off conditions. The flow evaluation during the optimization process is made through 2.5D Navier‐Stokes computations on chimera grids. The optimization technique used is an evolutionary algorithm, with a dynamic adaptation of the covariance matrix (CMA‐ES). Geometric and aerodynamic constraints have been considered through a dynamic penalization technique of the cost function.

Solutions obtained have been analyzed and compared to the reference initial configuration. In term of cost functions improvement, 5.71 per cent drag reduction has been obtained for landing, and 2.89 per cent improvement on climb index at take‐off.

Compared to the global optimization process, the use of a sequential approach can be quite efficient.

This paper presents a first step for the introduction of recent advanced methods into a design process of high‐lift configurations in an industrial environment.

The purpose of this paper is to study the main landing gear (MLG) mechanism configuration.

Mechanism kinematics and dynamics, stress analysis and sizing of the MLG structural members, and fatigue issues related with the mechanism operation. Spreadsheet solutions were incorporated to this survey to analyze the most conceivable loading situations, and important factors of the mechanism design for an initial evaluation of safety implications.

MLG design approach along with conservative fatigue design factors lies in the area of accepted limits in commercial aircraft industry.

MLG loading associated with landing as well as those associated with ground maneuvers (steering, braking and taxiing) contribute significantly to fatigue damage, along with the stresses induced by manufacturing processes and assembly. The application of FEA methods for the design of the landing gear does not always guarantee a successful approach to the problem solution, if precise analytical solutions are not available in advance.

From the investigation of this incident of fractured struts of the MLG it is confirmed that the reduction in Pintle Housing diameter on the upper part has contributed to the avoidance of damaging the fuel tank above the MLG that would lead to a catastrophic event. On the other hand, the airframe of the SKY-Jet was proved efficient for a belly landing with minor damages to the passengers and heavier damages for the aircraft.

On-line vibration monitoring sensors hooked up to the landing gear strut and Pintle House would greatly enhance safety, without relying in optical surveys in hard to access and inspect areas of the landing gears mechanisms housings.

Analytic methods were adopted and spreadsheet solutions were developed for the MLG main loading situations, along with design issues concerning mechanism kinematics and dynamics, stress analysis and sizing of the MLG structural members, as well as fatigue issues related with the mechanism operation. Spreadsheet solutions were incorporated to this survey to analyze the most conceivable loading situations, and important factors of the mechanism design for an initial evaluation of safety implications.

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.

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.

The study shows the feasibility of box-wing configuration for VTOL aircraft.

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.

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.

A proposal of the perspective solution of the general aviation aircraft control system is presented. The objective of the proposed concept for the control system is to assist pilots with limited aviation training by: automatic stabilization of the aircraft's attitude, altitude, airspeed, and heading and decoupling of the flight controls. The structure and main functions of the control system is presented, and method of control laws synthesis is proposed. Flight control system is based on the model‐following design technique. Two kinds of flight control systems are taken into consideration. The first solution is based on the optimal full‐state feedback controller, the second one is the simplified controller, using the easy observed states for feedback loop only. The project calculation of the flight control system for PZL‐110 “Koliber” aircraft, computer simulations and preliminary flight testing results will be presented.

Unconventional configuration aircrafts are not often designed because of many problems, mainly with stability and trim. However, they could be very promising. The problems can be compensated by extraordinary performance and some flying characteristics. The three-surface aircraft, presented in the paper, is such a configuration – problems and profits are both present, but advantages seem to be more prevalent. This paper aims to present main assumptions for a new, three-surfaces aircraft design, its evaluation according to flying quality requirements and the discussion on selected performance characteristics. The paper completes with the first experimental results of flight tests of a 40 per cent scaled model.

Aerodynamic computations were made using panel method code (KK-AERO, PANUKL). Stability analysis was done using SDSA package, developed within the SimSAC project.

Initial design assumptions and numerical analysis results were proven during flight tests.

The paper contains results of numerical analysis, which were crucial in designing the layout of the new, three-surface aircraft.

This paper presents an original approach to design a new, unconventional aircraft. The approach and results could be useful in other projects.

The main purpose of this study was to determine the basic aerodynamic characteristics of the airliner Tu-154M at the wide range of the overcritical angles of attack and sideslip angles, i.e. α = −900° ÷ 900° and β = −900° ÷ 900°.

Wind tunnel tests of the Tu-154M aircraft model at the scale 1:20 were performed in a low-speed wind tunnel T-3 by using a six-component internal aerodynamic balance. Several model configurations were also investigated.

The results of the presented studies showed that at the wide range of the overcritical angles of attack and sideslip angles, i.e. α = −900° ÷ 900° and β = −900° ÷ 900°, the Tu-154M aircraft flap deflection affected the values of the drag and lift coefficients and generally had no major effect on the values of the side force and pitching moment coefficients.

The model vibration which was the result of flow separation at high angles of attack was the wind tunnel test limitation.

Studies of the airliner aerodynamic characteristics at the wide range of the overcritical angles of attack and sideslip angles allow assessment of the aircraft aerodynamic properties during possible unexpected situations when the passenger aircraft is found to have gone beyond the conventional flight envelope.

There are no social implications of this study to report.

The presented wind tunnel test results of the airliner aerodynamic characteristics at overcritical angles of attack and sideslip angles is an original contribution to the existing not-too-extensive database available in the literature.

IN this turbine‐engined state‐of‐the‐art review it is relevant to look at the problem of jet noise which, to say the least, causes annoyance — ranging from mild to outraged protestation. Indeed, in the USA, there are currently law suits to the tune of $2·5 billion based on aircraft noise, the litigants being situated within the environs of Los Angeles International Airport.

The purpose of this paper was to elaborate the performance model of the remotely piloted aircraft systems (RPAS) which was destined for simulations of the construction characteristics, airspeeds and trajectory of flight in the controlled, non-segregated airspace according to the standard instrument departure and arrival procedures (SIDs and STARs).

This study used systems engineering approach: decomposition of RPAS performance model into components, relations and its connection with components of controlled the airspace system. Fast-time simulations (FTS) method, which included investigation of many scenarios of the system work, minimizing the number of input variables and low computing power demand, is also used.

Performance envelope of many fixed-wing RPAS was not published. The representative RPAS geometry configuration was feasible to implement. Power unit model and aerodynamic model needed to be accommodated to RPAS category. The range of aircraft minimum drag coefficient differed in the investigated range of take-off mass and wing loading.

Fixed-wing RPAS of small and medium categories cover take-off mass (25–450 kg), wing loading (40–900 N/m²) and power loading (8–40 W/N).

This is a research on integration of the RPAS in the controlled, non-segregated airspace. The results of the work may be used in broadening the knowledge of the RPAS characteristics from the perspective of operators, designers and air traffic services.

The elaborated performance model of the RPAS used the minimum number of three input variables (take-off mass, wing loading and power loading) in identification of the complete RPAS characteristics, i.e. construction features (aerodynamic, propulsion and loads) and flight parameters (airspeeds and flight trajectory).

This paper aims to apply a pavement design by LEDFAA for a sample airport, and design results involving layer thickness, modulus and cumulative damage factor (CDF) achieved are shown in figures.

Finite element (FE) simulation is applied for sample airport pavement and based on results involving stress and strain, CDF amount is shown by using related equations. To analyze the accuracy of modeling, a comparison has been made between the values of ABAQUS and case study results at Denver International Airport (DIA).

The present study includes a comparison between the two conventional methods for runway pavement design. There is linear relation between layered elastic design (LED) and FE method results, so CDF rate achieved by the FE method is always smaller than the LED method. To assess the accuracy of the applied modeling with ABAQUS software, the validation was done using the deformations under the concrete slabs of DIA. The results are compatible with the results acquired from the case study, and the high accuracy of modeling was approved. This research shows that B-777 on rigid pavements and A-340-500/600 on flexible pavements have the most CDF contribution, among other aircrafts. Also, CDF rate for any aircraft in the LED method is higher than the FE method.

To assess the accuracy of the applied modeling with ABAQUS software, the validation was done using the deformations under the concrete slabs of DIA. The results are compatible with the results acquired from the case study, and the high accuracy of modeling was approved.

What insights might attending to the cyclical history of colonially imposed environmental change experienced by Indigenous peoples offer to critical intellectual projects concerned with race? How might our understanding of race shift if we took Indigenous peoples' concerns with the usurpation and transformation of land seriously? Motivated by these broader questions, in this chapter, I deploy an approach to the critical inquiry of race that I have tentatively been calling anticolonial environmental sociology. As a single iteration of the anticolonial environmental sociology of race, this chapter focuses on Native (American) perspectives on land and experiences with colonialism. I argue that thinking with Native conceptualizations of land forces us to confront the ecomateriality of race that so often escapes sight in conventional analyses. The chapter proceeds by first theorizing the ecomateriality of race by thinking with recent critical theorizing on colonial racialization, alongside Native conceptualizations of land. To further explicate this theoretical argument, I then turn to an historical excavation of the relations between settlers, Natives, and the land in Rhode Island that is organized according to spatiotemporal distinctions that punctuate Native land relations in this particular global region: the Reservation, the Plantation, and the Narragansett.