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Performance differences between the aircraft types are natural and they inevitably cause problems in the air traffic system, particularly when slower aircraft types are followed by faster types in a climb or cruise queue. This paper presents the excess fuel consumption impact of aircraft performance differences in the air traffic environment. For this purpose, both climb and cruise phases of a flight mission are analyzed. Revision of the airworthiness regulations and air traffic procedures are suggested. The need for a flight level – cruise performance categorization is also recommended.

The purpose of this paper is to develop a new tool for aircraft performance analysis and optimization.

In this paper, the methodology of converting nomogram curves into mathematical functions is presented. Aircraft performance nomograms represent graphical interpretation of influence of several variables on performance such as environmental conditions, runway conditions and aircraft mass. The aircraft performance nomograms are converted in mathematical functions that describe several independent variables’ influence on aircraft performance parameters. To achieve greater accuracy in calculation of aircraft performance parameters, it is necessary to determine mathematical functions presented by dependent variable variations with several independent variables. The method of determining mathematical functions is illustrated on Fokker 100 landing gear extended net climb gradient determination graph.

To evaluate model, it was necessary to determine net climb gradient both graphically and analytically using model and compare the results. After solving both analytically and graphically, it was concluded that results are a match. During model evaluation, it was observed that model has a lot of advantages such as it has great precision of calculation, requires less time to calculate results and has minimum error possibility.

Final result of digitalization of aircraft performance nomograms is software production. The usage of this software can reduce flight planning and aircraft exploitation costs in several different manners. Airliners can produce such a software for those types of aircraft where there is no software provided from aircraft manufacturer.

Digitalization of aircraft performance nomogram has never been analyzed before, although there is a possibility of this particular methodology implementation in a practical manner in aviation industry.

The intention of this paper is to compare the performance of five Chipmunk aircraft, and to investigate the assumption that the performance of any operational aircraft can be considered to be representative of that type of aircraft. All the aircraft were tested, with the same instrument panel fitted, and were weighed in order to determine the variation in weight and centre of gravity. Flight tests were then conducted to investigate the following aspects of performance: turning, climbing, drag, engine power, stalling and spinning. The results, reduced from the readings taken during flight tests, showed that there are two main causes of variation between the performances of the aircraft. First the age and condition of the engine were seen to affect the power dependent aspects of performance. Secondly there was a wide variation of profile drag which was probably due to distortion of the airframes.

Throughout an aircraft development process, the conceptual design phase is an extremely important milestone; hence, the quality and success of this step directly affect the overall cost and lead time of the project. Because of this fact, the purpose of this study is to provide outputs and suggestions to the designing engineer regarding the requirements for reducing overall design time as well as costs and creating an ideal design at the early phases of the project by optimizing the aircraft development process.

The system has been prepared parametrically and presents some performance specifications for the aircraft in the early phases of the design, for example, coefficients for lift C_L as well as drag C_D and weight as well as fuel estimations. The software uses a combination of well-known design techniques within just one platform in contrast to many other applications. Because of this feature, it is not needed to use different sub-platforms which would require an appropriate environment and even though would lead to complications with regard to the connectivity. The system also presents relevant information about the aircraft performance like velocity versus load factor (V-n) diagrams, maximum turn rate of climb, turn rate and climb angle graphs in contrast to many other open-source conceptual design platforms.

In this study, authentic General Dynamics F-16 Fighting Falcon and McDonnell Douglas F-15 Eagle data were used as input to the system, and advanced geometric and/or performance graphs were obtained and compared to the literature where a good agreement of the results was observed. These results with regard to the aircraft performance are typically product specific and quite rare in the literature. These data obtained by use of the software during the aircraft design are, thus, of major interest, especially for the design of new aerospace platforms. In this study, all of these graphs (especially the remarkable V-n diagram) are obtained on one platform.

The aircraft conceptual design and analysis system software provides information and suggestions regarding the requirements for reducing the overall design time, reducing the design costs and creating an optimized design at the early phases of a project by optimizing the aircraft development process within just one convenient, that is, user friendly, platform, where it uses a combination of varying methodologies. Besides presenting one interface, which is quite typical for conceptual design tools, it allows applications of methods like vortex lattices and finite differences for obtaining aerodynamic performance parameters.

Temperature anomalies in the upper troposphere have become a reality as a result of global warming, which has a noticeable impact on aircraft performance. The purpose of this study is to investigate the total air temperature (TAT) anomaly observed during the cruise level and its impact on engine parameter variations.

Empirical methodology is used in this study, and it is based on measurements and observations of anomalous phenomena on the tropopause. The primary data were taken from the Boeing 747-8F's enhanced flight data recorder, which refers to the quantitative method, while the qualitative method is based on a literature review and interviews. The GEnx Integrated Vehicle Health Management system was used for the study's evaluation of engine performance to support the complete range of operational priorities throughout the entire engine lifecycle.

The study's findings indicate that TAT and SAT anomalies, which occur between 270- and 320-feet flight level, have a substantial impact on aircraft performance at cruise altitude and, as a result, on engine parameters, specifically an increase in fuel consumption and engine exhaust gas temperature values. The TAT and Ram Rise anomalies were the focus of the atmospheric deviations, which were assessed as major departures from the International Civil Aviation Organizations–defined International Standard Atmosphere, which is obvious on a positive tendency and so goes against the norms.

Necessary fixed flight parameters gathered from the aircraft's enhanced airborne flight recorder (EAFR) via Aeronautical Radio Incorporated (ARINC) 664 Part 7 at a certain velocity and altitude interfacing with the diagnostic program direct parameter display (DPD), allow for analysis of aircraft performance in a real-time frame. Thus, processed data transmits to the ground maintenance infrastructure for future evaluation and for proper maintenance solutions.

A real-time analysis of aircraft performance is possible using the diagnostic program DPD in conjunction with necessary fixed flight parameters obtained from the aircraft's EAFR via ARINC 664 Part 7 at a specific speed and altitude. Thus, processed data is transmitted to the ground infrastructure for maintenance to be evaluated in the future and to find the best maintenance fixes.

This paper aims to clarify the flight dynamics characteristics and improve the flight performance for large-scale morphing aircrafts. With specific focus on the effects of morphing on mass distribution, aerodynamics and flight stability, the study aims to develop the dynamic model, outline the morphing strategies design and evaluate the flight stability in transient stage of morphing.

The mode of relaxing the rigidity condition was opted, which introduced the functions of position of center of mass and moments of inertia with respect to the morphing parameters, and yielded a parameter-dependent flight dynamics model. The morphing strategies were designed by optimizing the morphing parameters with the corresponding performance metric of each mission segment, where the aerodynamics was estimated concurrently by DATCOM. Based on the decoupled and linearized longitudinal parameter-dependent model, the flight stability in transient stage of morphing was evaluated based on Hurwitz rules, with the stability condition proposed.

The research suggests that the longitudinal flight stability in transient stage of morphing can be evaluated by the relationship of aerodynamic pitching moment derivatives and the effects of morphing on the mass distribution, which results in a constraint on the morphing rate.

The aerodynamics is computed under quasi-steady aerodynamic assumption in low morphing rate and only the longitudinal flight stability is analyzed. Therefore, researchers are encouraged to evaluate the lateral stability and aerodynamics in high morphing rate.

The paper includes implications for the improvement of the flight performance of a multi-mission morphing aircraft and the design of the flight control system.

Methods of dynamic modeling and morphing strategies design are proposed for large-scale morphing aircrafts, and the condition of flight stability in transient stage of morphing is obtained. The results provide reference to research works in the field of dynamics and control of large-scale morphing aircrafts.

The preliminary aircraft design process comprises multiple disciplines. During performance analysis, parameters of the design mission have to be optimized. Mission performance optimization is often challenging, especially for complex mission profiles (e.g. for unmanned aerial vehicles [UAVs]) or hybrid-electric propulsion. Therefore, the purpose of this study is to find a methodology that supports aircraft performance analysis and that is applicable to complex profiles and to novel designs.

As its core element, the developed method uses a computationally efficient C++ software “Aircraft Performance Program” (APP), which performs a segment-based mission computation. APP performs a time integration of the equations of motion of a point mass in the vertical plane. APP is called via a command line interface from a flexible scripting language (Python). On top of APP’s internal radius of action optimization, state-of-the-art optimization packages (SciPy) are used.

The application of the method to a conventional climb schedule shows that the definition of the top of climb has a significant influence on the resulting optimum. Application of the method to a complex UAV mission optimization, which included maximizing the radius of action, was successful. Low computation time enables to perform large parametric studies. This greatly improves the interpretation of the results.

The scope of the paper is limited to the methodology that allows for advanced performance analysis at the conceptual and preliminary design stages with an emphasis on novel propulsion concepts. The methodology is developed using existing, validated methods, and therefore, this paper does not contain comprehensive validation. Other disciplines, such as cost analysis, life-cycle assessment or market analysis, are not considered.

With the proposed method, it is possible to obtain not only the desired optimum mission performance but also off-design performance of the investigated design. A thorough analysis of the mission performance provides insight into the design’s capabilities and shortcomings, ultimately aiding in obtaining a more efficient design.

Recent developments in the area of hybrid or hybrid-electric propulsion systems have shown the need for performance computation tools aiding the related design process. The presented method is especially valuable when novel design concepts with complex mission profiles are investigated.

The purpose of this paper is to define minimum cost technique of turbo fan transport aircraft in the presence of dynamic change of aircraft performance. Results can be practical applicable in airlines for achieving minimal operation costs.

Logarithmic differential is applied for defining conditions in order to achieve optimal Mach number for minimal climb cost. This condition is solved numerically by using Newton‐Ramphson method, to obtain optimal Mach number distribution with altitude. Conclusion about optimal top of climb (TOC) is defined after analyses for different aircraft mass and cost indexes.

Proposed method of minimum cost climb resulting in potential savings up to 5 per cent compared to Aircraft Flight Manual climb law. Proposed method also made correction of climb law and optimal TOC under existence of aircraft performance degradation.

Use of defined climb law and optimal TOC will minimize cost of en route flight profile.

At present, there is no definition of climb technique for minimum cost of en route flight profile, under dynamic degradation of aircraft performance. Final results are standardized to become applicable and easy to use with modern and old type of flight management system.

The purpose of this paper is to present a literature review on human factors in aircraft maintenance and to analyze and synthesize the findings in the literature on human factors engineering in aircraft maintenance.

The review adopts a threefold approach: searching and collecting the scientific literature; sorting them on the basis of relevance and applications; and review of the scientific evidences. Broad areas of aircraft maintenance regulations are identified and each area was explored to study the level of scientific growth and publications. Notable theories, models and concepts are being summarized.

Application of human factor principles in aviation spread beyond the technical arena of man-machine interface. The discipline has created a great impact on aircraft design, operations and maintenance. Its applications have percolated into design of aircraft maintenance facilities, task cards and equipment. Human factor concepts are being used for maintenance resource management. The principles are applied to shape the safety behavior and culture in aviation maintenance workplace. Nevertheless, the review unfolds immense potential for future research.

Research outcomes of non-aviation studies are also reviewed and consolidated to extend the applications to the aviation industry.

This review would be a consolidated source of information confining to the physical aspect of human factors engineering in aircraft maintenance. It is intended to serve as a quick reference guide to the researchers and maintenance practitioners.

It brought out the benefits of adopting the principles of human factor engineering in aircraft maintenance. Application of human factor philosophy ensures enhanced safety in air transport, personal safety and well-being of maintenance personnel.

This is a unique review based on aircraft maintenance regulations that are baseline performance standards made mandatory by regulatory authorities. Therefore, the review has been considered to be made on aircraft maintenance regulatory requirements that surpass corporate or competitive strategies in aviation maintenance organization.

With the objective to assess potentially performant hybrid-electric architectures, this paper aims to present an aircraft performance level evaluation, in terms of range and payload, of the synergies between a hybrid-electric energy system configuration and a cryogenic fuel system.

An unmanned aerial vehicle (UAV) is modeled using an aircraft performance tool, modified to take into account the hybrid nature of the system. The fuel and thermal management systems are modeled looking to maximize the synergistic effects. The electrical system is defined in series with the thermal engine and the performance, in terms of weight and efficiency, are tracked as a function of the cooling temperature.

The results show up to a 46 per cent increase in range and up to 7 per cent gain on a payload with a reference hybrid-electric aircraft that uses conventional drop-in JP-8 fuel. The configuration that privileges a reduction in mass of the electric motors by taking advantage of the cryogenic coolant temperature shows the highest benefits. A sensitivity study is also presented showing the dependency on the modeling capabilities.

The synergistic combination of a cryogenic fuel and the additional heat sources of a hybrid-electric system with a tendency to higher electric component efficiency or reduced weight results in a considerable performance increase in terms of both range and payload.

The potential synergies between a cryogenic fuel and the electrical system of a hybrid-electric aircraft seem clear; however, at the present, no detailed performance evaluation at aircraft level that includes the fuel, thermal management and electric systems, has been published.