Paweł Głowacki

Effect of the atmosphere on the performances of aviation turbine engines

Abstract The paper presents how the parameters defining the state of the atmosphere: pressure, temperature, humidity, are affecting performance of the aircraft turbine engines and their durability. Also negative impact of dust pollution level is considered as an important source of engine deterioration. Article highlights limitation of the aircraft takeoff weight (TOW) and requirements for length of the runways depending on weather condition changes. These problems stem from the growing “demand” of gas turbine engines for an air. The highest thrust engines have air mass flow more than 1000 kg/s. Engine inlet ice formation is presented as a result of weather conditions and inlet duct design features.

Safety performance indicators assessment for small aircraft airframe systems

Safety performance indicators are the parameters used for monitoring and assessing safety performance. Such factors are determined based on available safety databases, collected on government level (in Poland Civil Aviation Authority) or by aircraft operators. Aircraft system failure during different flight phases can cause an accident or an incident. Polish Civil Aviation Authority between other data bases manages two important ones called: European Coordination Centre for Aviation Incident Reporting Systems (ECCAIRS) and Aircraft Continuing Airworthiness Monitoring (ACAM).General Aviation (GA) operates mainly aircraft with MTOM<5700 kg powered by the single piston engine. At present, reliability of GA aircraft systems in Poland is unknown. Increasing size of this fleet in Poland requires taking necessary measures in order to establish safety risks and safety performance targets for GA fleet. The authors have performed processing of the data included in available databases analysing airframe failures based on criteria like: phases of flight, ATA chapters concerning aircraft systems and the category of occurrence. The goal of this article is to present method of the current reliability of GA aircraft systems assessment. The results of this analysis can support the decisions of supervisory authorities in the areas where security threats are most important also can help production organizations in identification of the aircraft systems, which required design changes.

Aircraft engines : analysis of reported systems failures in Polish aviation during years 2008-2015

Aircraft engine failure during different aircraft flight phases can cause accidents or incidents. ICAO Annex 19 requires from each state establishing the state safety program (SSP) and from the subordinate aviation organizations safety management system (SMS). Point 5.2.1 of Annex 19 instructs to establish safety database, which should be used for effective analysis of actual and potential safety deficiencies. Such analysis should lead to determining necessary measures in order to improve safety. Polish Civil Aviation Authority among other databases manages an important one called European Coordination Centre for Aviation Incident Reporting Systems (ECCAIRS). The authors have done a laborious processing of the data contained in that database analysing engine failures based on criteria like phases of flight, ATA chapters concerning powerplant and category of the occurrence. Separately, under consideration were taken engines installed on aircraft with an MTOM <5700 kg (mainly General Aviation) and for aircraft with MTOM > 5700 kg (commercial aviation). The article presents a proposed method of predicting the number of events, the alert levels for the next years and for ATA chapters’ determination, assuming a normal distribution (Gaussian). It is one of the first attempts to use the actual data contained in the database of events in Poland. The results of this analysis can support the decisions of supervisory authorities in the areas where security threats are most important.

INFLUENCE OF THE SELECTED EXPLOITATION TASKS ON AIRLINE OPERATING COST AND FLIGHT SAFETY TAKING AS AN EXAMPLE TURBOFAN ENGINE

The total cost of the aircraft maintenance was in 2012 about

ASSESSMENT OF THE AIRFRAME SYSTEMS AFFECTING SAFETY RISKS CAUSED BY LARGE AIRCRAFT

80 billion, including maintenance, repair and overhaul, ie. MRO market (Maintenance, Repairs and Overhaul), the operators of these aircraft have spent about

Balancing Energy Processes in Turbine Engines

60.7 billion – of which 40% were direct maintenance costs of the engines. It can be concluded that main influencer on airline direct maintenance costs are spending for power plants. The article shows that the appropriate exploitation of the engine, leading not only to the total operating costs (mainly the cost of fuel and maintenance) reduction. Also through continuously engine health monitoring, resulting in a higher reliability, and thereby increases the safety of flying and – what is now especially important – by decreasing fuel consumption reduces greenhouse gas and exhaust toxic components emissions. The modern aircraft engine and its basic performances were described. Based on data, analysis from approximately twenty thousand flights of the specific operator and self-experience, the benefits from the use of specific maintenance and operational tasks are presented. Results of the calculations were demonstrated which proved that engine life extension between overhaul (TBO) has impact on the operator’s maintenance reserves reduction, positive cash flow and fuel cost savings. The article confirms that it need not be contradiction between aircraft operator economic effect, and the improvement of safety of flying.

Aviation : environmental threats

Hazard is a safety condition that could cause or be a part of unsafe aircraft operation. It also has an impact on aviation safety related to aircraft systems as well as services. Safety risk is a part of so-called safety management and is the predicted probability and severity of the outcomes of a hazard. Aircraft utilized by airlines and cargo operators which have MTOM >5700 kg are defined by authors as a large aircraft and have to be treated in their systems reliability analysis separately from small aircraft. Despite the fact that both types of aircraft categories events are included in the same databases European Coordination Centre for Aviation Incident Reporting Systems (ECCAIRS) and Aircraft Continuing Airworthiness Monitoring (ACAM), due to different predominant systems failures could not be considered in the same way. The authors have performed processing of the data contained in available databases analysing large aircraft airframe systems faults, which were assigned to the specific ATA chapters. The most frequently occurring defects of the aircraft systems were identified. The goal of this article is to present a method of the current reliability of large aircraft systems assessment. Based on it, the authors are proposing a way of safety risk estimation and prediction of the safety levels for the next two years. The results of this analysis may support the decisions of supervisory authorities in the areas where security threats are most important. They can also help aircraft operators with identification of the aircraft systems, which require special attention.

Operations reliability study of small aircraft powered by piston engines

Abstract The article discusses the issue of balancing energy processes in turbine engines in operation in aeronautic and marine propulsion systems with the aim to analyse and evaluate basic operating parameters. The first part presents the problem of enormous amounts of energy needed for driving fans and compressors of the largest contemporary turbofan engines commonly used in long-distance aviation. The amounts of the transmitted power and the effect of flow parameters and constructional properties of the engines on their performance and real efficiency are evaluated. The second part of the article, devoted to marine applications of turbine engines, presents the energy balance of the kinetic system of torque transmission from main engine turbines to screw propellers in the combined system of COGAG type. The physical model of energy conversion processes executed in this system is presented, along with the physical model of gasodynamic processes taking place in a separate driving turbine of a reversing engine. These models have made the basis for formulating balance equations, which then were used for analysing static and dynamic properties of the analysed type of propulsion, in particular in the aspect of mechanical loss evaluation in its kinematic system.

ICAO aviation occurrence categories significantly affecting aviation safety in Poland from 2008 to 2015

Based on the available information and authors self-assessments, this article presents turbine engine exhaust gases effect on the environment, especially near to the aircraft and helicopters during their engines idle setting and take-offs. The concentration level of pollutants in gas turbine exhaust and its relation to the temperature and time of the combustion process is discussed. The article presents diffusion of the aircraft turbine engine exhaust in the airport area, focusing on aircraft take-off manoeuvre. The authors would like to draw attention of the aviation professionals to the fact that amount of exhaust from the turbine engine is so significant that may adversely change the ambient air near to the aircraft. Consequently, smaller amount of oxygen with increased level of carbon monoxide during engine start –up and idle can be a threat to the maintenance staff health. Also high emission level of the nitrogen oxides, especially during take-off and climb is indifferent for the environment. The paper gives an example of real fuel consumption and toxic gases emissions in the so-called landing and takeoff cycle (LTO) and during long-range flight. Turbine engines noise distribution and its intensity because of complex aerodynamic and thermodynamic processes is presented.