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The purpose of this study is to develop and describe a process which can be applied to develop new methods in the context of preliminary aircraft sizing in a successful and efficient way.

The tasks to development new aircraft sizing methods are systematically analyzed. In particular, repeating and nonrepeating tasks and common or unique tasks. Then ordered in a sequence and described generically.

A development process for new aircraft design methods which are necessary for new technologies or configurations is introduced and explained step by step.

Introducing the capability to deal with new technologies or configurations, aircraft design tools or aircraft concepts requires new sizing methods.

The paper presents a systematic approach which can be used to develop a great amount of new sizing methods with a comparable usability and quality standard in an efficient and effective way.

Development assurance level (DAL) is the measurement of the rigor of development assurance tasks performed to functions or items. The DAL assignment is an important process of aircraft system development that can make the reliability and safety of the system stay at acceptable levels. This paper aims to propose an optimization approach for the DAL assignments to minimize the development cost of aircraft systems.

The mathematical model for the DAL assignment optimization has been developed on the basis of the given expressions of objective function and constraints. In addition, a hybrid algorithm model synthesizing the advantages of genetic algorithm (GA) and Tabu search (TS) has been proposed to solve the optimization problem of the DAL assignment.

The results of the case study show that the proposed hybrid algorithm is more efficient and effective than the exhaustive method as well as the pure GA.

The proposed approach can be applied in the development of aircraft systems, and it has great significance in minimizing the development cost as well as keeping the system reliability and safety at an acceptable level.

The constrained optimization method has been applied in the DAL assignments, the corresponding mathematical model has been built and a hybrid evolutionary algorithm has been proposed to solve the optimization problem.

Discusses the requirements for refuelling civil airliners, particularly under pressure refuelling. Analyses the problems that can arise and demonstrates how advancing technology has changed the appearance and efficiency of many components, particularly with reference to the control panel. Describes in detail the workings of a typical system; aspects of control of fuel quantity in refuelling; refuel control panels; and fuel gauges, with particular reference to the Boeing 777.

The purpose of this paper is to define reliability requirements to be imposed on electric engines to assure similar or higher value of mean time between failures (MTBF) for mixed piston-electric propulsion configurations when compared to classic and unconventional piston engine configurations.

Reliability estimation was done using mathematical model of safety of light aircraft commercial operations. The model was developed on the basis of Federal Aviation Administration and National Transport Safety Board data. The analysis was conducted for numerous piston and electric configurations. It allowed comparison of selected solutions and definition of relation between electric engine MTBF and MTBF calculated for entire mixed piston-electric propulsion system.

It was found that, from reliability point of view, mixed piston-electric engine propulsion is attractive alternative for classic single- and twin-piston configuration. It would allow to at least doubling of MTBF for propulsion without increase of operational cost.

Rationale behind exploiting electric propulsion in aviation is provided. Relation between electric engine reliability and entire propulsion reliability was identified and defined. Minimum requirements concerning MTBF value for electric engine application in aviation was assessed. Conclusions from this study can be used for definition of requirements for new aircraft and by the regulatory authorities.

Originality consists in use of real accident statistics included in mathematical model of safety for assessment of MTBF for various classic and novel piston and piston-electric engine configurations of light aircraft. Output from the study can be exploited by the industry.

The purpose of this study is to investigate the influence of the technical and operational specifications of the Small Aircraft Transport System (SAT/SATS) to the achieved safety level.

Safety estimation was made with the use of mathematical model of safety of light aircraft in commercial operations developed on the basis of Federal Aviation Administration (FAA) data. The analysis was conducted for two different SATS business models based on Direct AiR Transport (DART) concept. It allowed for the investigation of the impact of technical specifications of the aircraft included into the SATS fleet as well as the selected elements of the applied business model on SATS safety level.

It was found that the proposed changes to DART system resulted in a significant improvement of safety. Mean Time Between Incidents and Accident (MTBIA) increased by 200 per cent. Additionally, the introduced alterations impacted the weights of particular domains and pilot’s error became less critical than the technical reliability.

It was shown that the application of new requirements influences both the safety level and the cost of operation, which was demonstrated within the ESPOSA and DART projects. Additionally, it was indicated that further effort to improve the light aircraft safety is absolutely necessary.

Originality consists in combining in one mathematical model both the aircraft configuration and the rules for business operation. Optimization of selected parameters of the system leads to a significant reduction in the accident number and to keeping the cost increment at a reasonable level. It was also found that the resulted improvement sometimes cannot be sufficient to consider a small aircraft operation fully safe, mainly owing to the numerous restrictions because of its small weight and loading capacity.

The purpose of this paper is to describe simulation research carried out for the needs of multi-sensor anti-collision system for light aircraft and unmanned aerial vehicles.

This paper presents an analysis related to the practical possibilities of detecting intruders in the air space with the use of optoelectronic sensors. The theoretical part determines the influence of the angle of view, distance from the intruder and the resolution of the camera on the ability to detect objects with different linear dimensions. It has been assumed that the detection will be effective for objects represented by at least four pixels (arranged in a line) on the sensor matrix. In the main part devoted to simulation studies, the theoretical data was compared to the obtained intruders’ images. The verified simulation environment was then applied to the image processing algorithms developed for the anti-collision system.

A simulation environment was obtained enabling reliable tests of the anti-collision system using optoelectronic sensors.

The integration of unmanned aircraft operations in civil airspace is a serious problem on a global scale. Equipping aircraft with autonomous anti-collision systems can help solve key problems. The use of simulation techniques in the process of testing anti-collision systems allows the implementation of test scenarios that may be burdened with too much risk in real flights.

This paper aims for possible improvement of safety in light-sport aviation.

This paper conducts verification of classic flight simulator software suitability for carrying out anti-collision systems tests and development of a flight simulator platform dedicated to such tests.

The purpose of this paper is to present a new computational framework to address future preliminary design needs for aircraft subsystems. The ability to investigate multiple candidate technologies forming subsystem architectures is enabled with the provision of automated architecture generation, analysis and optimization. Main focus lies with a demonstration of the frameworks workings, as well as the optimizers performance with a typical form of application problem.

The core aspects involve a functional decomposition, coupled with a synergistic mission performance analysis on the aircraft, architecture and component levels. This may be followed by a complete enumeration of architectures, combined with a user defined technology filtering and concept ranking procedure. In addition, a hybrid heuristic optimizer, based on ant systems optimization and a genetic algorithm, is employed to produce optimal architectures in both component composition and design parameters. The optimizer is tested on a generic architecture design problem combined with modified Griewank and parabolic functions for the continuous space.

Insights from the generalized application problem show consistent rediscovery of the optimal architectures with the optimizer, as compared to a full problem enumeration. In addition multi-objective optimization reveals a Pareto front with differences in component composition as well as continuous parameters.

This paper demonstrates the frameworks application on a generalized test problem only. Further publication will consider real engineering design problems.

The paper addresses the need for future conceptual design methods of complex systems to consider a mixed concept space of both discrete and continuous nature via automated methods.

Explains the development of an ultrasonic fuel gauging system by Smiths Industries in response to Boeing’s desire for a system which offers greater reliability. Looks at components and considerations and discusses current developments.

ANY aircraft development or innovation is news. Where it is specifically or related to powerplant it invariably becomes big news, with the potential of overseas users and national prestige uppermost in the mind. The recent keen competition for engine sales in the American market received due prominence, and with the three contestants all still in the field and sharing the largest order book in aeronautical history, the debut of this new generation of engines is eagerly awaited. Now when a substantial step forward in engine fundamentals and/or manufacturing techniques has been made, the tendency is to suppose that further advance will be small and some way off. But the fascination of the aerospace business is that there is yet no sign of slowing down in the rate of progress, and it is interesting to speculate on what may be around the corner and to ask, what next? A review of development over the last decade is illuminating and provides a lead to further discussion.

The purpose of this paper is to analyze and compare the performance of several different UAV trajectory tracking algorithms in normal and abnormal flight conditions to investigate the fault‐tolerant capabilities of a novel immunity‐based adaptive mechanism.

The evaluation of these algorithms is performed using the West Virginia University (WVU) UAV simulation environment. Three types of fixed‐parameter algorithms are considered as well as their adaptive versions obtained by adding an immunity‐based mechanism. The types of control laws investigated are: position proportional, integral, and derivative control, outer‐loop nonlinear dynamic inversion (NLDI), and extended NLDI. Actuator failures on the three channels and increased turbulence conditions are considered for several different flight paths. Specific and global performance metrics are defined based on trajectory tracking errors and control surface activity.

The performance of all of the adaptive controllers proves to be better than their fixed parameter counterparts during the presence of a failure in all cases considered.

The immunity inspired adaptation mechanism has promising potential to enhance the fault‐tolerant capabilities of autonomous flight control algorithms and the extension of its use at all levels within the control laws considered and in conjunction with other control architectures is worth investigating.

The WVU UAV simulation environment has been proved to be a valuable tool for autonomous flight algorithm development, testing, and evaluation in normal and abnormal flight conditions.

A novel adaptation mechanism is investigated for UAV control algorithms with fault‐tolerant capabilities. The issue of fault tolerance of UAV control laws has only been addressed in a limited manner in the literature, although it becomes critical in the context of imminent integration of UAVs within the commercial airspace.