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This paper aims to present the results of aerodynamic calculation of impact the main rotor on the fuselage and the tail of a light gyroplane. This kind of vehicle is a type of rotorcraft which uses a non-powered rotor in autorotation to develop lift and engine-powered propeller to provide the thrust. Both of them disturb the flow around the gyroplane body (gyroplane fuselage and tail) and influence on its static stability. The main goal of the presented research was to find the magnitude of this influence. To measure this effect, the main stability derivatives changes of gyroplane body were investigated.

The CFD analysis of the complete gyroplane was made. Computation was performed for the model of gyroplane which was equipped with the two sub-models of the main rotor and the engine-powered propeller. Both of them were modelled as the actuator discs. This method allows to compute the aerodynamic impact of rotating components on the gyroplane body. All aerodynamic analysis was made by the MGAERO software. The numerical code of the software bases on the Euler flow model. Next, the resulting aerodynamic coefficients were used to calculate the most important stability derivatives of the gyroplane body.

The result obtained by computation presents the change in the most important aerodynamic coefficients and stability derivatives of the gyroplane body caused by the impact of its main rotor. Moreover, the result includes the change of the aerodynamic coefficients and stability derivatives caused by change of the main rotor configuration (change of rotation rate and angle of incidence) and change of the flight condition (gyroplane angle of attack sideslip angle and flight speed).

Analysis of the main rotor impact will be very useful for evaluation of dynamic stability of the light gyroplane. Moreover, the results will be helpful to design the horizontal and vertical tail for the light gyroplane.

This paper presents the method of the numerical analysis of the static stability of the light gyroplane’s body. The results of analysis present the impact of disturbance generated by the rotating main rotor on the static stability of the gyroplane body. Moreover, the impact of the main rotor configuration change and the flight condition change on the static stability were investigated too. The evaluation of the gyroplane’s body static stability was made by the stability derivatives. The methodology and obtained result will be very useful for analysis of the dynamic stability of the light gyroplanes. Moreover, the results will be helpful during design the main components of the gyroplane like vertical and horizontal tail.

The purpose of this paper is to study the conceptual design and optimisation of a compound gyroplane. A study of a compound gyroplane configuration and its characteristics was performed to develop a sizing program.

The vertical takeoff and landing capabilities of a helicopter are particularly important. The need for efficient hover and the effectiveness of forward flight in the helicopter can cause conflicts within the design process. The designers usually wish to increase the helicopter's maximum forward speed. Recently, the compound aircraft is one of the concepts considered for the purpose of expanding the flight envelope of rotorcraft. The study of the compound gyroplane showed its advance capabilities for this purpose. Understanding its characteristics, a number of calculations are conducted to implement a sizing program for compound gyroplanes based on the conventional helicopter sizing process.

The results of the sizing program were validated using existing aircraft data such as the Challis Heliplane, Carter Copter, FB‐1 Gyrodyne, and Jet Gyrodyne. The program is appropriate to size a compound gyroplane at the conceptual design phase. An optimisation study was also performed to enhance sizing results. The compromise between the rotor lift sharing factor and the ratio of the wing span (Bw) to rotor diameter (D) was solved by choosing the total gross weight (TOGW) as the objective function, while the design variables are compromising factors. The optimum results showed that the TOGW of all four kinds of compound gyroplanes was considerably reduced.

A conceptual sizing program for unconventional compound aircraft was developed. The study showed that an optimum design process is necessary to enhance the sizing results.

THE advantages and disadvantages of the fixed wing for gyroplanes are examined. On the simplest assumptions an expression for the percentage load taken by the fixed wing of a gyroplane is derived. The values so arrived at are compared with those found by experiment and the discrepancy between the two is explained in terms of the increased downwash at the centre of the disc of the gyroplane. It is shown that as much as 50 per cent of the weight of the aircraft can be taken by the wing at top speed with moderate wing area and the most suitable setting. The advantages of an adjustable wing from the point of view of rotor speed control are pointed oat. The Lift/Drag of the combination is raised by 2 over the L/D of the rotor alone. The stability of gyroplanes is discussed.

SINCE 1929, a number of tests have been made at New York University on a new type of rotating aerofoil system, invented by Walter Kreiser and Walter Rieseler, and developed by E. Burke Wilford, of the Pennsylvania Aircraft Syndicate.

FOR the benefit of students who wish to take up responsible positions in the aircraft industries, the University College of Hull confers a Diploma in Aeronautics. Part of the training for this Diploma is given by the Hull Municipal Technical College.

The purpose of this paper is to describe the results of investigations of parachute rescue systems (PRS) for light gyrocopters.

Although the investigations were conducted in both stages simultaneously, i.e. experimental mechanics approach and numerical simulations, the paper is focussed mainly on the experimental part of the work. To ensure the safety of experimental works (i.e. for both experimenters and bystanders), the authors applied unmanned, remotely controlled scale models of autogyro for the PRS testing in the air.

The critical problem for successful use of the PRS is that the rotation of the rotor blades must be stopped when the main parachute opens, otherwise the influence of the rotor on the improper opening process of the parachute may cause the whole PRS to become useless.

The existing regulations for the use of unmanned aircraft impose the limitation upon the organisation of in-flight tests of PRS, i.e. the maximum take-off mass of the tested gyrocopter models is limited, and a full-scale test needs the approval of European Aviation Safety Agency (EASA).

The research contributes to increasing the safety level for gyrocopter users. The authors elaborated the original PRS, which currently is in the process of patenting.

Originality of the work consists of both an innovative PRS, which has never been tested before, and the results of experimental investigations, which cover both ground tests carried on static or moving stands and in-flight testing.

FLIGHT is the result of displacing air by surfaces and utilizing the reactive forces so created to lift, propel and control the craft.

The deck‐landing qualification test series on Aerospatiale's Dauphin SA 365N (naval version) helicopter have just been successfully completed off the coast of Brest.

NUMEROUS difficulties are encountered in any attempt to ascertain the loads which come into action on a gyroplane rotor blade, and the stresses which these loads impose on the blade. The loads are not steady but variable, complicated and subject to intractable fluctuations. In consequence the blades are in a continual state of agitation. Even when various simplifying assumptions are made the resulting differential equations of motion do not readily yield to conventional methods of treatment. So far as the modes of free vibration are concerned the analysis is relatively simple, but so far as the stresses in forced vibration are concerned the difficulties are formidable. In this paper it will be assumed that the loading over the blade is steady at any instant of a given flight condition. Subject to this restriction, the stresses in the blade may be found to any required degree of approximation by the generalised theorem of three moments suitably modified. In addition the gyroscopic moments of a blade and its frequency of “Happing” vibration will be found on the assumption that the blade is rigid and regard being had to imposed rotation.

ONE of the most puzzling problems of aviation at the present time is to come to any sort of conclusion as to the precise place in the future scheme of things of the type of gyroplane so aptly named “Autogiro” by its inventor.