The finite volume method was used to study the characteristic of contaminated aviation fuel with the aim of reducing its flammability and post-impact fire. The flammability levels between pure Jet A-1 and contaminated Jet A-1 are compared using their flashpoints and fire points before and after the introduction of Liquid Nitrogen. Upon heating different mixing ratios (4:1, 3:1, and 2:1), results are analyzed to identify the best volume ratio exhibiting the highest reduction in flammability. Analysis shows that the mixing ratio of 2:1 not only froze but increased the flashpoint of the mixture from (48 ˚C–50 ˚C) to 64 ˚C. For the mixing ratio of 3:1, there was a rise in flashpoint to about 56 ˚C and partial freezing was seen at the topmost surface. At a mixing ratio of 4:1, it was observed that the effect of liquid nitrogen on Jet A-1 was minimal leading to a slight rise in its flash point (50 ˚C). Thus, liquid Nitrogen had a substantial effect on the flammability and flash point of Jet A-1 when mixed in the ratio (2:1) with a freezing time of 30 seconds and an unfreezing time of 17.5 minutes. Hence, Liquid Nitrogen can be used for the flammability reduction of Jet A-1.
{"title":"LIQUID NITROGEN INJECTION INTO AVIATION FUEL TO REDUCE ITS FLAMMABILITY AND POST-IMPACT FIRE EFFECTS","authors":"Abdulbaqi Jinadu, Olalekan Adebayo Olayemi, Ayodeji Akangbe, Abdul-Haleem Olatinwo, Volodymyr Koloskov, Dmytro Tiniakov","doi":"10.3846/aviation.2023.19729","DOIUrl":"https://doi.org/10.3846/aviation.2023.19729","url":null,"abstract":"The finite volume method was used to study the characteristic of contaminated aviation fuel with the aim of reducing its flammability and post-impact fire. The flammability levels between pure Jet A-1 and contaminated Jet A-1 are compared using their flashpoints and fire points before and after the introduction of Liquid Nitrogen. Upon heating different mixing ratios (4:1, 3:1, and 2:1), results are analyzed to identify the best volume ratio exhibiting the highest reduction in flammability. Analysis shows that the mixing ratio of 2:1 not only froze but increased the flashpoint of the mixture from (48 ˚C–50 ˚C) to 64 ˚C. For the mixing ratio of 3:1, there was a rise in flashpoint to about 56 ˚C and partial freezing was seen at the topmost surface. At a mixing ratio of 4:1, it was observed that the effect of liquid nitrogen on Jet A-1 was minimal leading to a slight rise in its flash point (50 ˚C). Thus, liquid Nitrogen had a substantial effect on the flammability and flash point of Jet A-1 when mixed in the ratio (2:1) with a freezing time of 30 seconds and an unfreezing time of 17.5 minutes. Hence, Liquid Nitrogen can be used for the flammability reduction of Jet A-1.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":"179 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136014055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"90TH ANNIVERSARY OF THE AMAZING AND HEROIC DEED OF STEPONAS DARIUS AND STASYS GIRĖNAS","authors":"Gintautas Bureika, Gediminas Vaičiūnas","doi":"10.3846/aviation.2023.19931","DOIUrl":"https://doi.org/10.3846/aviation.2023.19931","url":null,"abstract":"Editorial. 90th anniversary of the amazing and heroic deed of Steponas Darius and Stasys Girėnas, Aviation, 27(3), pp. 129–130.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136014058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-21DOI: 10.3846/aviation.2023.19264
Petro Volodymyrovych Lukianov, Volodymyr Volodymyrovych Kabanyachyi
This paper analyses the available mathematical models of flight simulators based on the Stewart platform. It was found that there is no model that describes the conditions for stable dynamic equilibrium operation of the Stewart platform as a function of a number of important motion parameters. In this context, a new physical model is proposed based on classical models of theoretical mechanics using the d’Alembert formalism, the concept of stable equilibrium of a mechanical system. This model mathematically separates the stable equilibrium of the flight simulator motion system from the general uniformly accelerated motion. The systems of equations obtained in the framework of the model connect the physical and geometrical parameters of the Stewart platform and make it possible to determine the reactions in the upper hinges of the platform support, the limit values of the position angles in the space of the base of the support of the Stewart platform, under which the condition of stable equilibrium operation of the Stewart platform is satisfied. The proposed physical model and the analytical relations obtained on its basis are of great practical importance: the operator controlling the operation of the Stewart platform-based flight simulator can control the range of parameters during training so as not to bring the flight simulator out of stable equilibrium.
{"title":"MATHEMATICAL MODEL OF STABLE EQUILIBRIUM OPERATION OF THE FLIGHT SIMULATOR BASED ON THE STEWART PLATFORM","authors":"Petro Volodymyrovych Lukianov, Volodymyr Volodymyrovych Kabanyachyi","doi":"10.3846/aviation.2023.19264","DOIUrl":"https://doi.org/10.3846/aviation.2023.19264","url":null,"abstract":"This paper analyses the available mathematical models of flight simulators based on the Stewart platform. It was found that there is no model that describes the conditions for stable dynamic equilibrium operation of the Stewart platform as a function of a number of important motion parameters. In this context, a new physical model is proposed based on classical models of theoretical mechanics using the d’Alembert formalism, the concept of stable equilibrium of a mechanical system. This model mathematically separates the stable equilibrium of the flight simulator motion system from the general uniformly accelerated motion. The systems of equations obtained in the framework of the model connect the physical and geometrical parameters of the Stewart platform and make it possible to determine the reactions in the upper hinges of the platform support, the limit values of the position angles in the space of the base of the support of the Stewart platform, under which the condition of stable equilibrium operation of the Stewart platform is satisfied. The proposed physical model and the analytical relations obtained on its basis are of great practical importance: the operator controlling the operation of the Stewart platform-based flight simulator can control the range of parameters during training so as not to bring the flight simulator out of stable equilibrium.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45206660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-20DOI: 10.3846/aviation.2023.19113
Julius Žvinys, D. Rudinskas
This paper analyzes the application of Controller Pilot Data Link Communication (CPDLC) technology to different air traffic control sectors. It also presents the analysis of the performed research and tests. A CPDLC program is being developed that is adapted for aerodrome flight control. The program takes into account the advantages and disadvantages of other software, as well as the recommendations of other authors. The program is developed using JAVASCRIPT and HTML programming languages. The tests of the developed CPDLC program are performed in the Expert NITA flight control simulator. The CAPAN method is used for data analysis. Analysis of changes in workload, language errors, and time saved using different communication methods during simulations is also performed.
{"title":"INVESTIGATION OF THE APPLICATION OF CPDLC TO AERODROME AIR TRAFFIC CONTROL PROCEDURES","authors":"Julius Žvinys, D. Rudinskas","doi":"10.3846/aviation.2023.19113","DOIUrl":"https://doi.org/10.3846/aviation.2023.19113","url":null,"abstract":"This paper analyzes the application of Controller Pilot Data Link Communication (CPDLC) technology to different air traffic control sectors. It also presents the analysis of the performed research and tests. A CPDLC program is being developed that is adapted for aerodrome flight control. The program takes into account the advantages and disadvantages of other software, as well as the recommendations of other authors. The program is developed using JAVASCRIPT and HTML programming languages. The tests of the developed CPDLC program are performed in the Expert NITA flight control simulator. The CAPAN method is used for data analysis. Analysis of changes in workload, language errors, and time saved using different communication methods during simulations is also performed.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45393985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-20DOI: 10.3846/aviation.2023.19244
Cristina Mínguez Barroso, Daniel Muñoz-Marrón
The air transport evolution has been littered with major air disasters, the occurrence of which has not only had the negative effects inherent to any disaster. Air accident investigation has provided a wealth of knowledge that has advanced the aviation industry and its safety. International Civil Aviation Organization has exercised international regulatory leadership since 1947, developing tools with international cooperation, such as the air accident investigation methodology. ICAO has forged a change in perspective on safety attributions or factors in different historical eras, using this methodology to deepen the understanding of the causes and thereby achieve aviation safety improvement. Authors aimed to analyze, through a detailed study of the world’s worst aviation accidents, their contribution to understanding the details of aviation safety culture. Beyond the technical issues and fatality rates, the necessary analysis is what knowledge researchers have gained from the beginning, exploring the attributions of reports and knowing what diverse factors have predominated in different eras. Descriptive analyzes of air disaster investigation have two objectives: to identify the beginnings of a global safety culture resulting from evolution in operational safety and to relate the different eras to the attributions of air accident investigations.
{"title":"MAJOR AIR DISASTERS: ACCIDENT INVESTIGATION AS A TOOL FOR DEFINING ERAS IN COMMERCIAL AVIATION SAFETY CULTURE","authors":"Cristina Mínguez Barroso, Daniel Muñoz-Marrón","doi":"10.3846/aviation.2023.19244","DOIUrl":"https://doi.org/10.3846/aviation.2023.19244","url":null,"abstract":"The air transport evolution has been littered with major air disasters, the occurrence of which has not only had the negative effects inherent to any disaster. Air accident investigation has provided a wealth of knowledge that has advanced the aviation industry and its safety. International Civil Aviation Organization has exercised international regulatory leadership since 1947, developing tools with international cooperation, such as the air accident investigation methodology. ICAO has forged a change in perspective on safety attributions or factors in different historical eras, using this methodology to deepen the understanding of the causes and thereby achieve aviation safety improvement. Authors aimed to analyze, through a detailed study of the world’s worst aviation accidents, their contribution to understanding the details of aviation safety culture. Beyond the technical issues and fatality rates, the necessary analysis is what knowledge researchers have gained from the beginning, exploring the attributions of reports and knowing what diverse factors have predominated in different eras. Descriptive analyzes of air disaster investigation have two objectives: to identify the beginnings of a global safety culture resulting from evolution in operational safety and to relate the different eras to the attributions of air accident investigations.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48144733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-05DOI: 10.3846/aviation.2023.18923
Iyad Alomar, Irina Yatskiv (Jackiva)
Aircraft maintenance is considered as one of the major expenditures of aircraft operating costs. Notwithstanding that the new aircrafts, engines, and aircraft hard time parts became more durable and maintainable, the maintenance cost is still too high as against other costs like fuel and operational crews. Moreover, aircraft maintenance should be carried out with a high level of safety and security standards. All aircraft maintenance operations are subject to regulations by regulatory authorities. Such authorities can be attributed to European Union Aviation Safety Agency (EASA), Federal Aviation Administration (FAA) and National Civil Aviation Authorities (NAA). The last two decades have become a turning point in the transition from the paper form of the introduction of accounting for aircraft maintenance technical operations into electronic systems, despite all the difficulties associated with these procedures. Such difficulties are not limited to regulatory authorities, personnel training and investment which is case-sensitive for small companies. Similar to all other sectors of logistics and transportation, digitalization can be one of the key engines of change in aviation, especially in the aviation maintenance; thus, the study of digitalization effects on aircraft maintenance processes at present is an important factor for improving the maintenance processes and reducing the cost of aircraft maintenance. The objective of this research is to define the ability of aircraft maintenance and repair organizations to transform their processes. To that end, a data collection method in the form of a survey was implemented within Maintenance, Repair and Overhaul Organizations (MRO) and among aircraft maintenance engineers. The survey results demonstrate that the aircraft maintenance industry is not yet fully prepared for moving into digitalization in aircraft maintenance processes. However, at the same time, the study indicates the readiness of the personnel involved in the industry to improve themselves and their skills. The industry should invest in the improvement of safety and quality of tasks subject to digitalization by means of development of reliable software/hardware, and provide suitable training for safety and quality personnel.
{"title":"DIGITALIZATION IN AIRCRAFT MAINTENANCE PROCESSES","authors":"Iyad Alomar, Irina Yatskiv (Jackiva)","doi":"10.3846/aviation.2023.18923","DOIUrl":"https://doi.org/10.3846/aviation.2023.18923","url":null,"abstract":"Aircraft maintenance is considered as one of the major expenditures of aircraft operating costs. Notwithstanding that the new aircrafts, engines, and aircraft hard time parts became more durable and maintainable, the maintenance cost is still too high as against other costs like fuel and operational crews. Moreover, aircraft maintenance should be carried out with a high level of safety and security standards. All aircraft maintenance operations are subject to regulations by regulatory authorities. Such authorities can be attributed to European Union Aviation Safety Agency (EASA), Federal Aviation Administration (FAA) and National Civil Aviation Authorities (NAA). The last two decades have become a turning point in the transition from the paper form of the introduction of accounting for aircraft maintenance technical operations into electronic systems, despite all the difficulties associated with these procedures. Such difficulties are not limited to regulatory authorities, personnel training and investment which is case-sensitive for small companies. Similar to all other sectors of logistics and transportation, digitalization can be one of the key engines of change in aviation, especially in the aviation maintenance; thus, the study of digitalization effects on aircraft maintenance processes at present is an important factor for improving the maintenance processes and reducing the cost of aircraft maintenance. The objective of this research is to define the ability of aircraft maintenance and repair organizations to transform their processes. To that end, a data collection method in the form of a survey was implemented within Maintenance, Repair and Overhaul Organizations (MRO) and among aircraft maintenance engineers. The survey results demonstrate that the aircraft maintenance industry is not yet fully prepared for moving into digitalization in aircraft maintenance processes. However, at the same time, the study indicates the readiness of the personnel involved in the industry to improve themselves and their skills. The industry should invest in the improvement of safety and quality of tasks subject to digitalization by means of development of reliable software/hardware, and provide suitable training for safety and quality personnel.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48589321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-05DOI: 10.3846/aviation.2023.18909
J. Leško, R. Andoga, R. Bréda, M. Hlinková, L. Fözö
This article describes research on the classification of flight phases using a fuzzy inference system and an artificial neural network. The aim of the research was to identify a small set of input parameters that would ensure correct flight phase classification using a simple classifier, meaning a neural network with a low number of neurons and a fuzzy inference system with a small rule base. This was done to ensure that the created classifier could be implemented in control units with limited computational power in small affordable UAVs. The functionality of the designed system was validated by several experimental flights using a small fixed-wing UAV. To evaluate the validity of the proposed system, a set of special maneuvers was performed during test flights. It was found that even a simple feedforward artificial neural network could classify basic flight phases with very high accuracy and a limited set of three input parameters.
{"title":"FLIGHT PHASE CLASSIFICATION FOR SMALL UNMANNED AERIAL VEHICLES","authors":"J. Leško, R. Andoga, R. Bréda, M. Hlinková, L. Fözö","doi":"10.3846/aviation.2023.18909","DOIUrl":"https://doi.org/10.3846/aviation.2023.18909","url":null,"abstract":"This article describes research on the classification of flight phases using a fuzzy inference system and an artificial neural network. The aim of the research was to identify a small set of input parameters that would ensure correct flight phase classification using a simple classifier, meaning a neural network with a low number of neurons and a fuzzy inference system with a small rule base. This was done to ensure that the created classifier could be implemented in control units with limited computational power in small affordable UAVs. The functionality of the designed system was validated by several experimental flights using a small fixed-wing UAV. To evaluate the validity of the proposed system, a set of special maneuvers was performed during test flights. It was found that even a simple feedforward artificial neural network could classify basic flight phases with very high accuracy and a limited set of three input parameters.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48272154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-25DOI: 10.3846/aviation.2023.18914
M. Stosiak, K. Urbanowicz, K. Towarnicki, A. Deptuła, Paulius Skačkauskas, T. Leśniewski
The paper indicates the frequent occurrence of transient states in hydraulic systems. Particular attention was paid to the phenomenon of water hammer – the causes and effects of this phenomenon. A complete analytical description of this phenomenon has not yet been developed. New theoretical models are still being developed and need to be verified experimentally. The paper focuses on presenting the development of experimental stands for the study of water hammer in hydraulic pipes. Subsequent modifications of the experimental stands for the speed of the shut-off valves and their tightness, as well as for the minimisation of the occurrence of the effects of the pulsation of the performance of the pump supplying the line under investigation, are presented. The stand presented as the final one also allows the testing of transients in hydraulic lines for various types of working fluid (oil, emulsion, distilled water).
{"title":"UNSTEADY FLUID FLOW IN PRESSURISED CLOSED PIPES IN EXPERIMENTAL BENCH EXAMPLES","authors":"M. Stosiak, K. Urbanowicz, K. Towarnicki, A. Deptuła, Paulius Skačkauskas, T. Leśniewski","doi":"10.3846/aviation.2023.18914","DOIUrl":"https://doi.org/10.3846/aviation.2023.18914","url":null,"abstract":"The paper indicates the frequent occurrence of transient states in hydraulic systems. Particular attention was paid to the phenomenon of water hammer – the causes and effects of this phenomenon. A complete analytical description of this phenomenon has not yet been developed. New theoretical models are still being developed and need to be verified experimentally. The paper focuses on presenting the development of experimental stands for the study of water hammer in hydraulic pipes. Subsequent modifications of the experimental stands for the speed of the shut-off valves and their tightness, as well as for the minimisation of the occurrence of the effects of the pulsation of the performance of the pump supplying the line under investigation, are presented. The stand presented as the final one also allows the testing of transients in hydraulic lines for various types of working fluid (oil, emulsion, distilled water).","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46532653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.3846/aviation.2023.18629
Pavithra Nagaraj, Adham Ahmed Awad Elsayed Elmenshawy, Iyad Alomar
As VIP passengers generally want to fly civil and executive jets where vibratory and acoustic environment is smoother than on the normal jets. Helicopter interior noise is generated by main and tail rotors, engines, main gearbox, and aerodynamic turbulence (Lu et al., 2018). Because of these sources, the tonal and broadband noise is incredibly high and needs to be reduced. Conventional passive system (soundproofing) is the best way to control the acoustic of the cabin whereas active systems (active vibration and noise control) are not completely reliable or applicable. The design of the soundproofing may be researched by simulation using one of these programs: ANSYS, SOLIDWORKS 2020 and ACOUSTIC analysis Vibroacoustic Monitoring (VAM) approach. The analyses were performed from frequency ranges, 5-10Hz and 0-2000Hz then transformed into frequency velocity domain using Proudman’s equations (Lu et al., 2017). Soundproofed ANSYS models are validated using instantaneous sound pressure levels measured within the helicopter during flight. The acoustic detection method for GAZELLE is also performed successfully in SOLIDWORKS for aluminum alloy and titanium alloy, this proves the relationship between acoustic power levels and material configuration. The noise coefficient responses of interior materials are used as main index for soundproofing helicopter interiors. The results of this research can be used for implementation of VAM approach for soundproofing helicopter interiors.
由于贵宾乘客通常希望乘坐振动和声学环境比普通飞机更平稳的民用和行政飞机。直升机内部噪声由主旋翼和尾桨、发动机、主变速箱和空气动力学湍流产生（Lu et al.，2018）。由于这些源，音调和宽带噪声非常高，需要降低。传统的被动系统（隔音）是控制机舱声学的最佳方式，而主动系统（主动振动和噪音控制）并不完全可靠或适用。隔音设计可以使用以下程序之一进行模拟研究：ANSYS、SOLIDWORKS 2020和声学分析-振动声学监测（VAM）方法。从5-10Hz和0-2000Hz的频率范围进行分析，然后使用Proudman方程将其转换为频率-速度域（Lu等人，2017）。使用飞行过程中直升机内测量的瞬时声压级验证了隔音ANSYS模型。GAZELLE的声学检测方法也在SOLIDWORKS中成功地用于铝合金和钛合金，这证明了声功率水平与材料配置之间的关系。直升机内部材料的噪声系数响应是直升机内部隔音的主要指标。该研究结果可用于直升机内部隔音VAM方法的实施。
{"title":"VIBROACOUSTIC SOUNDPROOFING FOR HELICOPTER INTERIOR","authors":"Pavithra Nagaraj, Adham Ahmed Awad Elsayed Elmenshawy, Iyad Alomar","doi":"10.3846/aviation.2023.18629","DOIUrl":"https://doi.org/10.3846/aviation.2023.18629","url":null,"abstract":"As VIP passengers generally want to fly civil and executive jets where vibratory and acoustic environment is smoother than on the normal jets. Helicopter interior noise is generated by main and tail rotors, engines, main gearbox, and aerodynamic turbulence (Lu et al., 2018). Because of these sources, the tonal and broadband noise is incredibly high and needs to be reduced. Conventional passive system (soundproofing) is the best way to control the acoustic of the cabin whereas active systems (active vibration and noise control) are not completely reliable or applicable. The design of the soundproofing may be researched by simulation using one of these programs: ANSYS, SOLIDWORKS 2020 and ACOUSTIC analysis Vibroacoustic Monitoring (VAM) approach. The analyses were performed from frequency ranges, 5-10Hz and 0-2000Hz then transformed into frequency velocity domain using Proudman’s equations (Lu et al., 2017). Soundproofed ANSYS models are validated using instantaneous sound pressure levels measured within the helicopter during flight. The acoustic detection method for GAZELLE is also performed successfully in SOLIDWORKS for aluminum alloy and titanium alloy, this proves the relationship between acoustic power levels and material configuration. The noise coefficient responses of interior materials are used as main index for soundproofing helicopter interiors. The results of this research can be used for implementation of VAM approach for soundproofing helicopter interiors.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48048961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-23DOI: 10.3846/aviation.2023.18641
M. Caetano
Studies on safety in aviation are necessary for the development of new technologies to forecast and prevent aeronautical accidents and incidents. When predicting these occurrences, the literature frequently considers the internal characteristics of aeronautical operations, such as aircraft telemetry and flight procedures, or external characteristics, such as meteorological conditions, with only few relationships being identified between the two. In this study, data from 6,188 aeronautical occurrences involving accidents, incidents, and serious incidents, in Brazil between January 2010 and October 2021, as well as meteorological data from two automatic weather stations, totaling more than 2.8 million observations, were investigated using machine learning tools. For data analysis, decision tree, extra trees, Gaussian naive Bayes, gradient boosting, and k-nearest neighbor classifiers with a high identification accuracy of 96.20% were used. Consequently, the developed algorithm can predict occurrences as functions of operational and meteorological patterns. Variables such as maximum take-off weight, aircraft registration and model, and wind direction are among the main forecasters of aeronautical accidents or incidents. This study provides insight into the development of new technologies and measures to prevent such occurrences.
{"title":"AVIATION ACCIDENT AND INCIDENT FORECASTING COMBINING OCCURRENCE INVESTIGATION AND METEOROLOGICAL DATA USING MACHINE LEARNING","authors":"M. Caetano","doi":"10.3846/aviation.2023.18641","DOIUrl":"https://doi.org/10.3846/aviation.2023.18641","url":null,"abstract":"Studies on safety in aviation are necessary for the development of new technologies to forecast and prevent aeronautical accidents and incidents. When predicting these occurrences, the literature frequently considers the internal characteristics of aeronautical operations, such as aircraft telemetry and flight procedures, or external characteristics, such as meteorological conditions, with only few relationships being identified between the two. In this study, data from 6,188 aeronautical occurrences involving accidents, incidents, and serious incidents, in Brazil between January 2010 and October 2021, as well as meteorological data from two automatic weather stations, totaling more than 2.8 million observations, were investigated using machine learning tools. For data analysis, decision tree, extra trees, Gaussian naive Bayes, gradient boosting, and k-nearest neighbor classifiers with a high identification accuracy of 96.20% were used. Consequently, the developed algorithm can predict occurrences as functions of operational and meteorological patterns. Variables such as maximum take-off weight, aircraft registration and model, and wind direction are among the main forecasters of aeronautical accidents or incidents. This study provides insight into the development of new technologies and measures to prevent such occurrences.","PeriodicalId":51910,"journal":{"name":"Aviation","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45543405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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