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The focus of this paper is to identify a method for defining the needs of logistical operational support based on the mean time to failure (MTTF) factor. The research was based on a helicopter intended for flight training. The MTTF indicator for selected equipment was determined based on failure data from previous flight operations. As the basic operational data for the developed method, the time from the beginning of the operation or the flight time from the last damage and the method of restoring airworthiness were selected. The MTTF and replacement index for the device were determined. The next step was to determine the index, based on selected probability distributions. The results were analyzed and presented in graphical form, and conclusions were drawn. Based on the MTTF index and replacement index, the logistics needs of selected devices were determined. The obtained results were compared with the actual exchanges of devices made in the year in question. The research proved that the MTTF reliability factor and the analysis of trends in value changes could be used to determine the needs for the logistical security of the operation process, particularly in relation to the equipment subject to accidental failures. This is important for maintaining high availability of an aircraft or other technical objects. [ABSTRACT FROM AUTHOR]

This article is focused on the research concerning the calculation of the durability of electrical machines installed in the electrical system of M-28 and C-130 Hercules aircraft. The article presents a method of predicting the service life of aircraft commutator machines, which are the primary source of electrical energy. The result of the research was the determination of the durability of bearings and coils of electrical machines operated on aircraft based on a flight profile analysis. It is problematic to directly measure the wear of bearings and windings of an electric machine on the aircraft. Their usage can be determined from the relation between their wear and the ambient temperature. This research can be used in practice to plan maintenance work on the analyzed aircrafts. [ABSTRACT FROM AUTHOR]

The paper presents an analysis of false triggers of fire protection systems installed on aircraft. They not only cause task interruption but also have a direct impact on flight safety, forcing the crew to land in a risky area. Simulation models of electronic actuators were developed to determine the conditions under which false alarms occur. Testing of the simulation models was carried out in the computational package Matlab-Simulink and Circum-Maker for different electrical disturbance generation conditions. The simulation of overvoltage, voltage drops and voltage decays in the on-board electrical network supplying the fire protection system, occurring during the start-up of aircraft engines and during the switching on and off of on-board high-power devices, was studied. The conducted studies have practical applications since the simulation results are an important element for planning experimental tests of the SSP-FK-BI executive blocks under electrical disturbance conditions. Based on the simulation and experimental studies, the conditions causing false tripping of the fire protection system and the parameters for selected disturbance factors have been determined. [ABSTRACT FROM AUTHOR]

Introduction: Although aviation is considered the safest mode of transportation, the annual number of pilots blinded by laser light cannot be understated. An analysis of the available statistics indicates that it is a widespread phenomenon. The stories told by the pilots show the consequences of these incidents, ranging from temporary sight loss to months of vision problems. The article also describes the current penalties for dazzling a pilot by laser light. Moreover, limited research has been conducted on the intensity of laser light of different wavelengths passing through the fairing and through standard glasses used by pilots. Understanding the effects of laser glare on pilots can help reduce adverse events and improve the ability of safety managers to develop safety procedures. Correctly designed transport systems enable effective route planning and order processing. Methods: Two types of easily available laser pointers, drawn at different distances from the aircraft, were analyzed and the intensity of the transmitted light was examined. Results: The results showed that the intensity decreases with distance and that the intensity is too low to harm the eye. In addition, it should not be forgotten that the light propagates in a cone which strengthens the illumination effect in the cabin and causes pilots to lose orientation. Practical application of the findings: They enable the identification of areas around the airport where the use of lasers should be prohibited. Practical Application: The possibility of determining the transition of laser light through the windscreen of the aircraft as well as its intensity under near real-life conditions. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop a model of the readiness and reliability of an aircraft to perform an air task. The applied research method uses quantitative statistical methods and Markov processes in order to create a mathematical algorithm to exploit a selected aircraft type. The paper presents a case study of the TS-11 "Iskra" aircraft. The results show that even if the probability of being on stand-by is low, the tasks can be completed by operating the entire fleet properly. [ABSTRACT FROM AUTHOR]

This paper is a continuation of research into the possibility of using fuzzy logic to assess the reliability of a selected airborne system. The research objectives include an analysis of statistical data, a reliability analysis in the classical approach, a reliability analysis in the fuzzy set theory approach, and a comparison of the obtained results. The system selected for the investigation was the aircraft gun system. In the first step, after analysing the statistical (operational) data, reliability was assessed using a classical probabilistic model in which, on the basis of the Weibull distribution fitted to the operational data, the basic reliability characteristics were determined, including the reliability function for the selected aircraft system. The second reliability analysis, in a fuzzy set theory approach, was conducted using a Mamdani Type Fuzzy Logic Controller developed in the Matlab software with the Fuzzy Logic Toolbox package. The controller was designed on the basis of expert knowledge obtained by a survey. Based on the input signals in the form of equipment operation time (number of flying hours), number of shots performed (shots), and the state of equipment corrosion (corrosion), the controller determines the reliability of air armament. The final step was to compare the results obtained from two methods: classical probabilistic model and fuzzy logic. The authors have proved that the reliability model using fuzzy logic can be used to assess the reliability of aircraft airborne systems. [ABSTRACT FROM AUTHOR]

The article describes the method of predicting the reliability and durability of an aircraft commutator, which is a primary source of electric energy in helicopters. Tests were conducted for 10 starter-generators. From this research it follows that the technical condition of brushes and bearings has a significant impact on the reliability of starter-generators. The reliability of starter-generators was determined based on the method consisting of two stages that was adopted: the first stage involved determining the density function of changes in diagnostic parameter depending on the operating time, but the second stage included the assessment of the reliability of bearings of the starter-generator taking into account the real flight profile. The first stage of the adopted method consisted of defining the dynamic model of changing the length of the starter-generator's brush, which became the probabilistic model. Subsequently, based on differential equations, Fokker–Planck partial differential equation was derived, which describes the process of increasing the brush wear in a probabilistic way. This method enables the prediction of the residual durability of the helicopter's starter-generator due to the change in a diagnostic parameter which is the wear of brushes during starter-generator operation. The second stage of this method allows determining the durability of starter-generator's bearings building upon the average helicopter's flight profile. Owing to the difficulty in measuring the wear of bearings, the relation between the durability of bearings and the temperature of surroundings can be applied by replacing the flight altitude with temperature. The reliability of the helicopter's starter-generator was determined based on the serial-type reliability structure. [ABSTRACT FROM AUTHOR]

One of the existing priorities of the European Union is to search for rational waste management and to keep such waste in the economic cycle, while meeting the highest safety requirements. The paper presents the results of environmental tests of composites based on the polyethylene (rPE) and polypropylene (rPP) matrix and reinforced with cellulose fibres (newsprint, NP). Raw materials were obtained by recycling post-consumer waste such as beverage bottles and newsprint. The composites were tested for their potential use as materials in cladding panels and acoustic barriers. Given that normative documents for these products do not define specific environmental requirements, the composites were tested for the release of dangerous substances, such as anions of inorganic compounds, heavy metals, volatile organic compounds (VOCs), and their impact on the environment. A detailed in-depth analysis of the mechanisms of release of substances (diffusion, dissolution, surface leaching and depletion) from the rPP/NP composite into surface water, groundwater and soil was carried out. In turn, emission of VOCs from the rPE (low-density:high-density (LD:HD)—50:50) and rPE (LD:HD—30:70) composites into indoor air was also carried out. Raw materials in the form of granulates and loose cellulose fibres, used to produce the composites, were also tested for their environmental impact. [ABSTRACT FROM AUTHOR]

This work focuses on research on obtaining and characterizing Al2O3/ZrO2 materials formed via slip casting method. The main emphasis in the research was placed on environmental aspects and those related to the practical use of ceramic materials. The goal was to analyze the environmental loads associated with the manufacturing of Al2O3/ZrO2 composites, as well as to determine the coefficient of thermal expansion of the obtained materials, classified as technical ceramics. This parameter is crucial in terms of their practical applications in high-temperature working conditions, e.g., as parts of industrial machines. The study reports on the four series of Al2O3/ZrO2 materials differing in the volume content of ZrO2. The sintering process was preceded by thermogravimetric measurements. The fabricated and sintered materials were characterized by dilatometric study, scanning electron microscopy, X-ray diffraction, and stereological analysis. Further, life cycle assessment was supplied. Based on dilatometric tests, it was observed that Al2O3/ZrO2 composites show a higher coefficient of thermal expansion than that resulting from the content of individual phases. The results of the life cycle analysis showed that the environmental loads (carbon footprint) resulting from the acquisition and processing of raw materials necessary for the production of sinters from Al2O3 and ZrO2 are comparable to those associated with the production of plastic products such as polypropylene or polyvinyl chloride. [ABSTRACT FROM AUTHOR]

The safety and reliability of railway transport requires new solutions for monitoring and quick identification of faults in the railway infrastructure. Electric heating devices (EORs) are the crucial element of turnouts. EORs ensure heating during low temperature periods when ice or snow can lock the turnout device. Thermal imaging is a response to the need for an EOR inspection tool. After processing, a thermogram is a great support for the manual inspection of an EOR, or the thermogram can be the input for a machine learning algorithm. In this article, the authors review the literature in terms of thermographic analysis and its applications for detecting railroad damage, analysing images through machine learning, and improving railway traffic safety. The EOR device, its components, and technical parameters are discussed, as well as inspection and maintenance requirements. On this base, the authors present the concept of using thermographic imaging to detect EOR failures and malfunctions using a practical example, as well as the concept of using machine learning mechanisms to automatically analyse thermograms. The authors show that the proposed method of analysis can be an effective tool for examining EOR status and that it can be included in the official EOR inspection calendar. [ABSTRACT FROM AUTHOR]

The present work deals with the evaluation of the effect of ZrO2 on the structure and selected properties of shapes obtained using the centrifugal slip casting method. The samples were made of alumina and zirconia. The applied technology made it possible to produce tubes with a high density reaching 99–100% after sintering. Very good bonding was obtained at the Al2O3/ZrO2 interphase boundaries with no discernible delamination or cracks, which was confirmed by STEM observations. In the case of Al2O3/ZrO2 composites containing 5 vol.% and 10 vol.% ZrO2, the presence of equiaxial ZrO2 grains with an average size of 0.25 µm was observed, which are distributed along the grain boundaries of Al2O3. At the same time, the composites exhibited a very high hardness of 22–23 GPa. Moreover, the environmental influences accompanying the sintering process were quantified. The impacts were determined using the life cycle analysis method, in the phase related to the extraction and processing of raw materials and the process of producing Al2O3/ZrO2 composites. The results obtained show that the production of 1 kg of sintered composite results in greenhouse gas emissions of 2.24–2.9 kg CO2 eq. which is comparable to the amount of emissions accompanying the production of 1 kg of Polyvinyl Chloride (PVC), Polypropylene (PP), or hot-rolled steel products. [ABSTRACT FROM AUTHOR]

The ongoing global climate change and the associated environmental degradation pose a threat to Europe and the rest of the world. Raw materials and energy are required to produce building materials, which are used for construction purposes. Resulting buildings and structures generate waste during construction, operation, and demolition, and they emit potentially harmful substances. Thus, the key to achieving climate goals is to support low-emission materials and technologies in the construction sector, significantly impacting the environment. In the European Union, building materials are not yet subject to mandatory sustainability assessment during the assessment and verification of constancy of performance (AVCP). Objective evaluation of construction materials' environmental impact requires it to be carried out based on production data on an industrial scale. This article presents the environmental impact of premixed gypsum-based plasters, commonly used in modern construction. Nine environmental indicators (global warming potential (GWP), depletion potential of the stratospheric ozone layer (ODP), acidification potential (AP), eutrophication potential (EP), formation potential of tropospheric ozone (POCP), abiotic depletion potential (ADP)-elements, ADP-fossil fuels, renewable primary energy resources (PERT), and nonrenewable primary energy resources (PERNT)) of premixed gypsum plasters based on natural and flue gas desulfurization (FGD) gypsum were estimated and discussed. Knowledge of the construction products' environmental impact is fundamental for creating reliable databases. AVCP of construction materials in the future will use the data collected during the voluntary environmental impact evaluation. [ABSTRACT FROM AUTHOR]

This paper focuses on the possibility of adapting the centrifugal slip casting method to obtain zirconia–alumina composite materials in the form of finished tube-shaped products. These types of products, due to their unique properties, can be utilised, for example, in the transport of aggressive substances, even in extreme temperatures or corrosive conditions. The study reports on the two series of zirconia–alumina composites differing in the content of ZrO2—2.5 and 25 vol%. The fabricated and sintered materials were characterised using scanning electron microscopy (SEM), X-ray diffraction (XRD) and stereological analysis. Moreover, a life cycle assessment (LCA) was provided in accordance with the requirements of the ISO 14044 and EN 15805 standards. The obtained data clearly show that the centrifugal slip casting method allows obtaining samples with high density and extremely uniform distribution of the ZrO2 phase in the alumina matrix. The stereological analysis results proved also that the addition of ZrO2 is effective in reducing the growth of Al2O3 grains during the sintering process. The phase analysis carried out by means of XRD showed that during the sintering process, in the case of composites with a lower ZrO2 content (2.5 vol%), the monoclinic to tetragonal transformation of ZrO2 was total, while for samples containing 25 vol% ZrO2, the monoclinic phase remained in a small amount in the final product. [ABSTRACT FROM AUTHOR]

Poland's economy as the sixth largest economy in the EU is painfully experiencing the effects of natural resource depletion, which extend to increasing prices and the growing dependence on foreign suppliers. The situation is particularly unfavorable in the construction sector, which is among the most resource- and energy-consuming areas of the economy. This paper juxtaposes the situation of Polish construction industry in the context of the national economy with the context of the evolving EU policies promoting green solutions. The resulting changes in Polish legislation, industry and society are identified. The implementation of selected Circular Economy (CE) aspects, outcomes, emerging challenges and future directions are discussed. The social aspects related to this transformation were analyzed based on a survey carried out among construction industry consumers. The results clearly highlight that individuals are aware of the need to protect the environment, but also indicate a strong necessity to educate the populace about the consequences of the excessive exploitation of the environment and the long-term benefits of CE solutions. [ABSTRACT FROM AUTHOR]

Energy saving is one of the strategic challenges facing our civilization today. Without decisive actions to reduce energy consumption, it is impossible to maintain the current standard of living. Energy consumption for heating and cooling purposes is one of the primary energy consumption sources in many countries. The external thermal insulation composite system (ETICS), which is today the most widely used solution in EU countries, increases buildings' energy efficiency. This article investigates the impact of producing cementitious adhesives, as part of ETICS with expanded polystyrene (EPS) or mineral wool (MW), on the natural environment using the cradle-to-gate life cycle assessment (LCA) method. Cementitious adhesives have a relatively low impact on most of the environmental indicators analyzed in the paper concerning other ETICS components. The paper aims to raise awareness of the importance of the environmental impact related to the production of cementitious adhesives. Knowledge of the construction products' environmental impact is fundamental for creating reliable databases, based on which, in the future, their environmental requirements will be determined. The environmental performance of building elements is essential for the correct determination of the buildings' sustainability. [ABSTRACT FROM AUTHOR]

External thermal insulation systems (ETICS) are relevant facade applications of functional components allowing to reduce energy consumption in buildings to fulfill the provisions of nearly Zero-Energy Buildings (nZEBs). ETICS systems generally are made of adhesives, thermal insulation material, renders with mesh reinforcement, primers, and finish coats. Their main parameters are thermal characteristics and durability, both determined by the specific composition of the systems. Growing concerns on the environment and depletion of natural resources drive the need for the determination of the environmental characteristic of ETICS due to its growing market demand. This analysis focuses on a life cycle assessment (LCA) of a commonly used EPS based ETICS system with four different renderings, produced in several locations. The scope of this study concerns raw materials extraction, transport, production, and energy provision up to the finished, packed, and ready-for-sale product at the factory gate. The authors compared the environmental impact allocated to the 1 m2 of the produced system by taking into account the thickness of EPS and within different environmental impact categories. The results of the current impacts were compared to those obtained five years earlier, considering the technological and environmental progress of the production process. [ABSTRACT FROM AUTHOR]