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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 derive and solve equations for the fuel required by internal combustion engine airplanes on trajectories with a constant rate of climb or descent. Three modes of flight are considered: constant angle of attack, constant speed, and constant Mach number.

Newton's second law of motion is used to derive the equations. These are Riccati equations or reduced to such equations after neglecting a small term. A change of variable transforms them into second order linear differential equations that are solved exactly.

Formulas are found for the weight of fuel, speed, altitude, horizontal distance, time to climb, and power required.

The formulas obtained have direct applications for the analysis of aircraft performances and mission planning.

The formulas obtained are new and fundamental for the analysis of aircraft dynamics.

AIRCRAFT engine designers who are looking again at propeller‐driven aircraft instead of turbo‐fan propulsion may show more than a passing interest in the experience of an amateur aviator at Redhill's Tiger Club.

It is used on more daily scheduled flights than any other propeller driven aircraft and is exceeded by only the Boeing 727, 737 and DC‐9. In continuous production since 1966, this aircraft has amassed more than seven million flying hours and its order book has now exceeded 800 units.

IN the age of the Jet and the Rocket, propeller driven aircraft still play key roles in virtually every field of aviation. The means of propulsion may be as old as powered flight itself, but the technology of propeller design is still constantly advancing to meet the requirements of new aircraft types. One of Britain's leading specialists in this field is Dowty Rotol Ltd which has a world wide reputation for the design and production of aviation propellers of all types.

OF all the civil aircraft currently being produced in Europe none would appear to have brighter prospects of success in the international market than the BAC One‐Eleven airliner. With the first flight still some weeks ahead, seven different operators have placed firm orders for forty‐five aircraft and a number of other airlines have declared their intention of con‐cluding purchases once the approval of the appropriate authorities have been obtained.

Purpose – The purpose of the chapter is to sketch the historical and evolutionary development of the Wichita Aircraft Manufacturing Cluster from inception to present and provide a descriptive narrative of aircraft industry knowledge spillovers currently driving effort to establish a Medical Device Manufacturing Cluster. The chapter illustrates how carbon-fiber composite materials knowledge and technology developed for use in the aviation industry is facilitating the creation and growth of medical device manufacturing.

Methodology/approach – We use an historical case study approach to trace the development of the aircraft cluster in the Wichita, KS metropolitan area. A number of technologies are identified that had initially been adopted by one firm but eventually diffused through other firms in the local cluster and ultimately throughout the industry.

Findings – In addition to providing examples of within industry knowledge spillovers, we provide an example of technology-based knowledge that is diffusing through the aircraft manufacturing industry and is now being used as the basis for establishing an unrelated industry manufacturing cluster. The use of carbon-fiber composites in aircraft manufacturing has diffused from one manufacturer to many in the industry. Subsequently, the knowledge base surrounding carbon-fiber composite materials is being used in a local R&D effort to create a second manufacturing cluster producing medical devices ranging from surgical instruments to joint-replacement implants.

Originality/value of paper – The chapter illustrates a unique example of a manufacturing cluster, intra-industry knowledge spillovers, and inter-industry knowledge spillovers to create a new manufacturing cluster.

The paper focuses on the evaluation of a light aircraft spin. The main purpose of this paper is to achieve reliable mathematical models of aircraft motion beyond stall conditions to subsequently predict spin properties based on calculation only. Another vitally significant objective is to verify whether the aerodynamic characteristics determined numerically are coherent with the wind tunnel measurements performed on the dynamically scaled aircraft models.

The analysis was carried out for two certified conventional light aircraft. The first part of the investigation is devoted to the verification of the simplified methods used to identify the aircraft recoverability from spinning steady-state turns and estimate the primary post-stall flight parameters. Then, the spin simulations were executed. The computational results were thereafter compared with the in-flight data recordings.

The study confirms the coincidence between the calculated spinning behaviour and the observed aircraft response during the flight tests. The mathematical models of aircraft spatial motion have been found to be credible for predicting spin properties. The simplified methods are reliable to determine the basic spin performance of light aircraft at the preliminary design stage, whereas the spin simulations enable recognition and comprehensive examination of all spin modes.

The outcomes of conducted calculation and comparisons of computational spin properties with flight test recordings have indicated that the qualitative assessment of spinning motion is enabled at each stage of the designing process.

The paper involves the comparison of the computational results with the recordings of spin in-flight tests and the correlation between calculated and experimentally obtained aerodynamics of light aircraft.

This is the first of two companion papers presenting the results of research into a contra‐rotating propeller designed to drive a super manoeuvrable micro air vehicle (MAV). The purpose of this first paper is to describe the design process and numerical analyses. The second paper is devoted to the experimental results verifying the computations.

Software based on the analytical formulas derived by Theodore Theodorsen was used in the design procedure. Three‐dimensional finite‐volume simulation, performed with the use of commercial software verified the results. Finally, two‐dimensional simulation was conducted to explore the effect of the propeller‐wing interaction. The meshes applied in these analyses are described.

Propeller geometry received as a result of the design procedure is presented. The computation results for different turbulence models applied are discussed. Time dependent characteristics of contra‐rotating propeller are presented as well as conclusions regarding propeller‐wing interaction.

Propeller was designed for a fixed wing aeroplane, not for helicopter rotor. Therefore, conditions characteristic for fixed wing aeroplane flight are analysed only. Reynolds numbers below 50000 are considered.

Designed contra‐rotating propeller can be used in fixed wing aeroplane if torque equal to zero is required. Software based on the formulas derived by T. Theodorsen can be used to design the propellers.

Software applied in the design procedure was originally developed by one of authors although it is based on the formulas derived by T. Theodorsen. Contra‐rotating propeller simulation results for different turbulence models are discussed for the first time. Moreover, unique time dependent characteristics of contra‐rotating propeller are presented.

This is the second of two companion papers presenting the results of research into a contra‐rotating propeller designed to drive a super manoeuvrable micro air vehicle (MAV) and is devoted to the experimental results. The first paper presented the design process and numerical analyses.

Most of experiments were conducted in the wind tunnel. Both contra‐rotating and conventional propellers were tested. The test procedures and equipment are described first. The attention is focused on the design of an aerodynamic balance used in the experiment. Then, the measurement error is discussed, followed by presentation of the wind tunnel results. Finally, an initial flight test of the MAV equipped with contra‐rotating propeller is briefly described.

Wind tunnel experiment results fall between theoretical results presented in the first part of the paper. The application of contra‐rotating propeller allowed to develop the propulsion system with zero torque. Moreover, the efficiency achieved appeared to be a few percent greater than that for a standard conventional propulsion system. The concept was finally proved during the first test flight of the new MAV.

The propeller was designed for a fixed wing aeroplane, not for helicopter rotor. Therefore, only conditions characteristic for fixed wing aeroplane flight are tested.

The designed contra‐rotating propeller can be used in fixed wing aeroplane if torque equal to zero is required.

Original design of the balance is described for the first time, as well as test procedures applied in this experiment. Most of wind tunnel test results are also new and never published before.