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The purpose of this study is to investigate the influence of gyroscopic effects on the dynamic stability and the response of light aircraft to manoeuvres following either a rapid deflection of the control surfaces or wind gust.

The analyses were conducted for several different mathematical models of aircraft motion, which allowed for the investigation of the relationship between introduced simplifying assumptions and the aircraft response, including non-linear terms in equations of motion expressing the influence of inertial coupling. The analytical and experimental methods (measurements in the wind tunnel for the scaled model and during flight tests of I-31T prototype aircraft) were used.

It was found that gyroscopic moments are induced mainly by the propeller, and their influence on dynamic stability of a light aircraft is negligible. However, these phenomena in manoeuvring flight investigation should not be excluded, although for general aviation (GA) aircraft, they are not strong. Hence, two types of gyroscopic effects depending on the level of steady flight disturbances were distinguished. The authors differentiated weak gyroscopic effects, corresponding to classical dynamic stability, and strong gyroscopic effects, corresponding to rapid manoeuvres.

Conclusions include some findings on the nature of gyroscopic effects (i.e. sensitivity of flight stability versus turboprop power unit parameters) and practical recommendations for aircraft designers dealing with new configurations of GA aircraft.

The analysis focuses on the assessment of the flight dynamics of light aircraft with a novel, compact, lightweight, fast-rotating turbopropeller engine and strong/weak gyroscopic effects.

The purpose of this paper is to describe an integrated approach to spin analysis based on 6-DOF (degrees of freedom) fully nonlinear equations of motion and a three-dimensional multigrid Euler method used to specify a flow model. Another purpose of this study is to investigate military trainer performance during a developed phase of a deliberately executed spin, and to predict an aircraft tendency while entering a spin and its response to control surface deflections needed for recovery.

To assess spin properties, the calculations of aerodynamic characteristics were performed through an angle-of-attack range of −30 degrees to +50 degrees and a sideslip-angle range of −30 degrees to +30 degrees. Then, dynamic equations of motion of a rigid aircraft together with aerodynamic loads being premised on stability derivatives concept were numerically integrated. Finally, the examination of light turboprop dynamic behaviour in post-stalling conditions was carried out.

The computational method used to evaluate spin was positively verified by comparing it with the experimental outcome. Moreover, the Euler code-based approach to lay down aerodynamics could be considered as reliable to provide high angles-of-attack characteristics. Conclusions incorporate the results of a comparative analysis focusing especially on comprehensive assessment of output data quality in relation to flight tests.

The conducted calculations take into account aerodynamic and flight dynamic interaction of an aerobatic-category turboprop in spin conditions. A number of manoeuvres considering different aircraft configurations were simulated. The computational outcomes were subsequently compared to the results of in-flight tests and the collected data were thoroughly analysed to draw final conclusions.

The purpose of this paper is to present application of multidisciplinary design optimisation (MDO) in redesign of a small composite aircraft. The redesign process was integration of the turboprop engine in a small composite aircraft. The process requires cooperation of specialists from many disciplines and definition of their tasks. For selected tasks, the authors present results of the calculation.

The authors used collaborative optimisation (CO) algorithm to solve the problem. They decomposed this complex process into a set of tasks in different engineering/research disciplines and used techniques and methods specific for each task (research/engineering discipline) to find a proper solution. The computer-aided design (CAD), computational fluid dynamics (CFD) and computational structural mechanics (CSM) commercial software were used as common tools as well as intentionally developed computer programmes were used as basic tools in some tasks, in particular, for aerodynamic optimisation, calculation of load and stability of aircraft. The exchange of data between separate tasks allowed achieving the main goal of complex design process.

Selected optimisation algorithm, CO, proved efficient for the authors’ purposes. The effectiveness of multidisciplinary optimisation depends as much on organisational parameters as it does on technical and technology parameters.

Multidisciplinary optimisation needs to be an integral part of analysis and design process. The successful optimisation results allowed to meet the requirements and to proceed to the next phase of work – preparing technical documentation for manufacturing the components necessary for integration of the airplane with the new engine.

Presented results of design process are a valuable example of how to achieve the final goal in an ongoing project.

OF all the fields of aeronautical endeavour, that of the twin‐engined executive aircraft is possibly the most competitive. Encompassing as it does, piston‐engined, turboprop‐, turbojet‐ and turbofan‐powered aircraft, this range of aircraft offers the executive traveller every possible variation in initial cost, operating cost, range, cruising speed, comfort and field performance that he is likely to require within a stated bracket.

The purpose of this paper is to present the challenges of turbine engine installation on small aircraft. The work was a part of the European Union project Efficient Systems and Propulsion for Small Aircraft, FP7 EU – Activity, 7.1.4. improving cost efficiency.

Few of the most interesting issues associated with replacing a piston engine with a turboprop engine were chosen: changes in engine bay cooling, air inlet, exhaust system, nacellès weight and parts reduction, flight tests and performance. The publication presents an approach to: design, assemble and test the small aircraft with a turboprop engine.

Replacement of piston engine by turbine was carried out. The full program of ground and flight test small aircraft has been successfully completed. Pros and cons of the new design are described in the paper.

Currently, aviation gasoline (AVGAS ) is increasingly being replaced by JET-A1 (kerosene-type fuels) or diesel fuel. The change concerns engine replacement and all the necessary additional components on the aircraft. This is consistent with the new directions of development of aviation: clean, green and eco design. Replacing the piston engine with a turbine allows improvement to performance and reduces operation cost.

The achieved results allow for identifying and highlighting new directions of aviation technology development. A significant added value is to draw attention to the necessity of preparing for future requirements and amendments in regulations for the new class of aircraft: general aviation SET(L) – single engine turboprop.

THE Rover Co. Ltd. was associated with Air Commodore Sir Frank Whittle during the early stages of the production of the original Whittle‐type turbojet engines in 1941–42. Two of their engines were taken over by Rolls‐Royce and after further development gave rise to the well‐known Nene and Derwent engines. At the conclusion of the Second World War the Company embarked on a development programme for small gas turbine units with the eventual goal being a unit suitable for installation in a motor car. This work is well‐advanced but no date has been given as the likely time at which a production version of the gas turbine driven car will be available.

Novel Feature Protects Airframe and Undercarriage Fairey Hydraulics, a member of the Fairey Holdings Group, has been selected by Westland Helicopters to design and manufacture the tricycle undercariage oleo legs for the new Lynx 3, military and W30–300 civil and military helicopters. In the event of unusually heavy landings, a special feature built into military versions, provides protection to both the aircraft structure and the undercarriage itself.

Development or upgradation of airplanes requires many different analyses, e.g. thermal, aerodynamic, structural and safety. Similar studies were performed during configuration change design of commuter category aircraft equipped with pusher turboprop engines. In this paper, thermo-fluid analyses of interactions of the new propulsion system in tractor configuration with selected elements of airplane skin are carried out. This study aims to check the airplane skin material, and its geometry, including the Plexiglas passenger window material degradation, due to hot exhaust gas plume impingement. The impact of change in exhaust stub angle and asymmetric inboard-outboard stubs on the jet thrust at various flight operating conditions like minimum off-route altitude and cruise performance is assessed.

Commercial software-based numerical models were developed. In the first stage, heat and fluid flow analysis was performed over a twin-engine airplane’s nacelle, wing and center fuselage with its powerplant mounted in the high wing configuration. Subsequently, numerical simulations of thermal interactions between the hot exhaust gases, which leave the exhaust system close to the nacelle, flaps and the center fuselage, were estimated for various combinations of exhaust stub angles with asymmetry between inboard-outboard stubs at different airplane configurations and operating conditions.

The results of the simulations are used to recommend modifications to the design of the considered airplane in terms of material selection and/or special coatings. The importance and impact of exhaust jet thrust on the overall aircraft performance are investigated.

The advanced numerical model for the exhaust jet-airplane skin thermal interaction was developed to estimate the temperature effects on the propeller blades and aircraft fuselage surfaces during different flight operating conditions with multiple combinations of stub orientations.

THE Twenty‐fifth S.B.A.C. Flying Display and Exhibition is to be held at Farnborough during the week Monday, September 5, to Sunday, September 11, promises to be one of the most interesting yet held as for the first time member companies of the Society have nominated for entry aircraft from member countries of the European A.I.C.M.A. (Association Internationale des Contructeurs de Materiel Aérospatial) that are powered by British engines. Seven European aircraft will be taking part, four of them sponsored by Bristol Siddeley Engines Ltd. and three by Rolls‐Royce Ltd. The dominant theme of the Show will be collaboration, and it is fitting that the foreign aircraft have been sponsored by the aero engine manufacturers as they have advanced farther along this road than the airframe companies. Between them, they have close associations with practically all the major engine manufacturers in the Western world. Apart from the models and displays which will be mounted by the major airframe and engine manufacturers reflecting their growing involvement with European projects, the stands of the Associate Members of the Society of British Aerospace Companies will have many examples of materials, techniques and equipment that these companies are producing in support of current programmes, some of which will be for the American military aircraft now on order for the Royal Air Force and the Royal Navy.

This paper aims to present the analysis of introduction of single engine turbo-prop aeroplane class in terms of certification specifications and flight crew licensing regulations.

Following the results of flight testing and additional performance and sizing calculations, the proposed class was placed among the existing aeroplane taxonomy in terms of performance, flight loads, mass penalty, fuel economy and several other factors. Concerning small air transport initiative, the new class was tried to be placed as a starting point in commercial pilot career.

The paper points the potential market for single engine turbopropeller aeroplanes and lists today obstacles in wider introduction. Therefore, remarks about required change of regulations and requirements for design process, as well as for crew licensing, are underlined.

The results of the study would be helpful in preliminary design of a new low-power turboprop aeroplane, as well as during tailoring the certification specifications.

The approach presented in this paper is a detailed extension of an original idea presented by author for the first time during Clean Sky/small air transport workshop.