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The purpose of this paper is to present the results of the preliminary design and optimization of the air-intake system and the engine nacelle. The work was conducted as part of an integration process of a turboprop engine in a small aircraft in a tractor configuration.

The preliminary design process was performed using a parametric, interactive design approach. The parametric model of the aircraft was developed using the PARADES™ in-house software. The model assumed a high level of freedom concerning shaping all the components of aircraft important from the point of view of the engine integration. Additionally, the software was used to control the fulfillment of design constraints and to analyze selected geometrical properties. Based on the developed parametric model, the preliminary design was conducted using the interactive design and optimization methodology. Several concepts of the engine integration were investigated in the process. All components of the aircraft propulsion system were designed simultaneously to ensure their compliance with each other.

The concepts of the engine integration were modified according to changes in the design and technological constraints in the preliminary design process. For the most promising configurations, computational fluid dynamics (CFD) computations were conducted using commercial Reynolds-averaged Navier–Stokes solver FLUENT™ (ANSYS). The simulations tested the flow around the nacelle and inside the air-delivery system which consists of the air-intake duct, the foreign-particles separator and the auxiliary ducts delivering air to the cooling and air-conditioning systems. The effect of the working propeller was modeled using the Virtual Blade Model implemented in the FLUENT code. The flow inside the air-intake system was analyzed from the point of view of minimization of pressure losses in the air-intake duct, the quality of air stream delivered to the engine compressor and the effectiveness of the foreign particles separator.

Based on results of the CFD analyses, the final concept of the turboprop engine integration has been chosen.

The presented results of preliminary design process are valuable to achieve the final goal in the ongoing project.

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.

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.

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.

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.

The aim of this paper is to present the results preparation of a new glass cockpit for a general aviation category airplane with a TP100 turboprop 180 kW engine. All the works were carried out within the framework of the European programme: “Efficient Systems and Propulsion for Small Aircraft” – ESPOSA.

As a part of the ongoing work, the avionics equipment available on the market were thoroughly analysed. Optimization of choice was defined at the level of costs, ergonomics and development requirements of the engine manufacturer. The paper presents the issues of the realized project and discusses its specific characteristics, such as advantages and disadvantages in comparison to the conventional analogue cockpit and the possibility of adaptation for the plane.

New avionics, ground and in-flight tests were carried out. The data were collected, which, together with an ergonomics assessment done by the pilot and the observer, confirmed the previously established technical and operational objectives.

Most airplanes, when being modernized, encounter minor or major problems. A new approach to upgrading the avionics, involving the exchange of a piston engine with a turbine engine, which is supported by 3D software, has allowed a significant reduction of working time and costs.

The achieved results allow specifying a plan of changes, necessary to adapt the aircraft to a new avionic system. However, an important value is to show a new development direction of the turbine engine implementation in general aviation aircrafts.

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 propulsion system integration of a turboprop aircraft, which has been developed for the basic trainer, was performed. The proper turboprop engine was selected among worldwide existing engines by the specific developed engine selection technique and trade‐off studies such as customer’s request for operational capability (ROC), propulsion system parameters, performance analysis with engine installed effects, future growth potential, integrated logistic support (ILS), maintainability, interfaces with the airframe, etc. The chin type air inlet with the plenum chamber was designed in consideration of the inclined configuration to minimize the propeller swirl effect, the inertial separation bypass device to reduce FOD, and the super‐ellipse and NACA‐1 profile lip to maximize the ram recovery. The air inlet was analyzed by a higher‐order source panel method considering propeller wake. The exhaust duct was designed through internal cross‐section area determination to maximize the cruising power as well as external configuration to maximize the effective power, to minimize the aerodynamic drag and to minimize the cockpit contamination by the exhaust gas. The proper oil cooler for the selected turboprop engine was determined with cooling requirements and the oil cooling inlet duct with NACA configuration was designed. The test of the propulsion system including the installation performance test with the effects of the air inlet, the exhaust duct, the propeller and the nose fuselage configuration was performed in the test cell.

Currently, in many countries, aviation safety regulations allow piston engines exploitation above Time Between Overhaul (TBO) recommended by manufacturers. Upon fulfillment of certain requirements, which are already included in the manufacturers’ documentation, TBO extension is granted. National Aviation Authority has approved exploitation of piston engines to something like quasi on-condition maintenance, which has no technical proof behind. This leads to the conclusion that the current, simple way of the engine’s life extension is not the best solution for maintaining flight safety. Aircraft piston engines TBO extension requires changes in the current exploitation system.

The paper provides methodology for aircraft piston engines on-condition exploitation based on engine flight parameters (from cruise and takeoff) and engine oil particles analysis. The paper describes a method of diagnostic limits for certain engine parameters and elements in the oil assignation assuming that they come under rules of normal distribution.

It has been found that piston engines installed on maximum takeoff mass <5,700 kg class aircraft are the second biggest contributor as a source of aviation events, thereby having a significant impact on aviation safety. Engine flight parameters and elements content in the oil meet Gaussian rules.

Introduction of the engine on-condition exploitation into operation practices reduces the operator’s engine direct maintenance cost and increases technical knowledge of the employees and has a positive impact on flight safety.

It is the first scientific description in Poland, which proposes an empirically proved methodology of the aviation piston engines on-condition exploitation.

The purpose of this paper is to create models that predict exergetic sustainability index (ESI) and environmental effect factor (EEF) values with high accuracy according to various engine parameters.

In this study, models were created to estimate ESI and EEF sustainability parameters in various flight phases for a business jet with a turboprop engine using the cuckoo search algorithm (CSA) method. The database used for modeling includes the various engine parameters (torque, engine airflow, gas generator speed, fuel mass flow, power and air-fuel ratio) obtained by running a business aircraft engine more than once at different settings and the actual ESI and EEF values obtained depending on these parameters. In addition, sensitivity analysis was performed to measure the effect of engine parameters on the models. Finally, the effect of the CSA number of nest (n) parameter on the model accuracy was investigated.

It has been observed that the models predict ESI and EEF values with high accuracy. As a result of the sensitivity analysis, it was seen that the air-fuel ratio had a greater effect on the output parameters.

These models are thought to assist in the exergetic environment analysis used to find the greatest losses for turboprop business jets and identify their causes and further improve system performance. Thus, they will be a useful tool to minimize the negative impact of business jet on environmental sustainability.

To the best of the authors’ knowledge, this study stands out in the literature because it is the first exergo-metaheuristic approach developed with CSA for business aircraft engine; moreover, the data set used consists of real values.