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1
Kokhan, V., T. Dudnyk, D. Sivoraksha i Т. Televna. "RESEARCH OF POSSIBILITY OF ARMOURING A CABIN OF TYPE Mi-8A HELICOPTER". Наукові праці Державного науково-дослідного інституту випробувань і сертифікації озброєння та військової техніки, nr 7 (21.05.2021): 40–48. http://dx.doi.org/10.37701/dndivsovt.7.2021.05.
Pełny tekst źródłaStreszczenie:
Given an urgent need to protect a crew of the type Mi-8 helicopter from firearms in the course of combat missions and lack of transparent armor for this type of helicopter in the Armed Forces of Ukraine, it was decided to conduct a theoretical and experimental research with regard to armouring a cabin of type Mi-8 helicopter.
The first stage of experimental research was laboratory (bench) research.
Samples of bulletproof glass measuring 500x500 mm and 12 and 18 mm thick were provided for testing. The purpose of research bench tests was to determine the degree of protection of the armored glass unit. The samples were fired at with 9 mm pistol bullets, ind. 57-H-181c (Makarov pistol), bullets 7.62 mm pistol cartridge, ind. 57-H-134c (Tokarev pistol) and 5.45 mm bullets, ind. 7H6 (AK-74 assault rifle).
The next stage of experimental research was to conduct research ground tests of armored glass of a Mi-8 helicopter crew cabin.
The purpose of research ground tests was to evaluate the protective properties of armored glass samples, based on the results of their firing with a single 5.45 mm bullet shots, ind. 7H6 (AK-74 assault rifle) at the shooting range.
Samples of armoured glass of the on-board technician and sight (right) glass intended for protection of the flight crew, systems and units of the cabin were presented for ground research tests.
The final stage of experimental research was the stage of research flight tests of the Mi-8MSB-B helicopter with 18 mm thick armored glass.
The purpose of research flight tests was as follows:
to determine changes in the main technical and operational characteristics of Mi-8MSB-B helicopter after installation of 18 mm thick armored glass;
to determine the possibility of using 18 mm thick armored glass on Mi-8 helicopters;
to assess the effectiveness and safety of armored glass for armouring Mi-8 helicopters’ cabins;
to determine peculiarities of using 18 mm thick armored glass on Mi-8 helicopters and peculiarities of Mi-8 helicopter operation with armored glass installed;
to obtain initial data for elaboration of tactical and technical (general) requirements for helicopters Mi-8 (particularly concerning the installation of armored glass), approved by Testing Program and Procedure for research flight tests of Mi-8MSB-B helicopter.
2
Кибальний, Михайло Юрійович, Андрій Павлович Дьомін, Сергій Олександрович Дегтяренко i Микола Іванович Москаленко. "Розрахункове дослідження аеродинамічних характеристик рульового гвинта вертольота типу Мі-8 з урахуванням інтерференції з несучим гвинтом на режимі висіння при боковому вітрі". Aerospace technic and technology, nr 2 (28.04.2021): 28–35. http://dx.doi.org/10.32620/aktt.2021.2.04.
Pełny tekst źródłaStreszczenie:
Under certain conditions of a helicopter flight, the main rotor can exert a rather strong effect on the tail rotor, changing its traction and power characteristics. The calculated and experimental characteristics of an isolated tail rotor under such operating conditions can differ significantly from those under conditions of interaction with the main rotor. The study of this phenomenon is an urgent task, since a change in the characteristics of the tail rotor and the conditions of its operation in the presence of the main rotor can cause a decrease in controllability margins and, as a consequence, the cause of an aircraft accident, for example, the so-called. "left rotation" of the helicopter. Since 1985, on helicopters from M. L. Mile, 42 aviation accidents occurred in units and subdivisions of the state and civil aviation of the USSR (and now Russia) due to helicopters falling into spontaneous left rotation. Over the past 10 years, 29 accidents (8 accidents and 21 accidents) have occurred for this reason. 29 helicopters were lost: 20 Mi-8, 5 Mi-24, 4 Mi-2. Experience shows that getting into an uncontrolled left rotation in almost 100% of cases ends with a collision of the helicopter with the ground and overturning it on the starboard side. The interaction of the main and tail rotor is most significantly manifested in the modes of horizontal flight with sliding at low speeds and hovering in crosswind conditions. This is due to the peculiarities of the formation of the main rotor vortex wake. In this article, the case of aerodynamic interference of the main rotor and several helicopter configurations in horizontal flight mode with the low speed with sliding (hovering in a crosswind) is considered. Using the methods of computational fluid dynamics, the degree of influence of the main rotor on the tail rotor was investigated in the described modes. The most severe operating modes of the tail rotor of each configuration have been determined. Based on the results of calculations, the most rational configuration of the tail rotor has been chosen, which has the greatest reserves of controllability under unfavorable operating conditions. The results obtained have been used in the design of a new perspective helicopter, modernization of the existing fleet, as well as improving the flight safety level.
3
Klimaszewski, Sławomir, Krzysztof Sajda i Sergiusz Szawłowski. "Preliminary System Safety Hazard Analysis of a Transport Helicopter SHM System". Journal of KONBiN 51, nr 2 (1.06.2021): 19–31. http://dx.doi.org/10.2478/jok-2021-0019.
Pełny tekst źródłaStreszczenie:
Abstract The purpose of this paper is to provide the Mi-8/17 helicopter Structural Health Monitoring (SHM) System Preliminary System Safety Hazard Analysis (PSSHA). The PSSHA identifies and classifies potential hazards, and the actions necessary to reduce or eliminate the risks resulting from the installation and operation of SHM System on board of the helicopter. The overall objective of the PSSHA is to establish that the potential Mi 8/17 helicopter modification does not introduce unacceptable hazard conditions to both the helicopter and personnel. The MIL-STD-882 risk assessment methodology is applied to assess hazards and risk acceptance levels for both hardware and software elements of the SHM system.
4
Pilipenko, O., D. Kolesnik, A. Berezniak i V. Shokha. "DAMAGING AND DESTRUCTION OF REDUCTION TRAINS OF MI-8 HELICPTER AND ITS MODIFICATIONS". Наукові праці Державного науково-дослідного інституту випробувань і сертифікації озброєння та військової техніки, nr 3 (28.05.2020): 92–105. http://dx.doi.org/10.37701/dndivsovt.3.2020.12.
Pełny tekst źródłaStreszczenie:
The results of quantitative factographic study of the Mi-8 helicopter (its modifications) reduction trains with different types of gear coupling, the destruction of which occurred while in flight due to the presence of preliminary material damage at the stage of production of the gear wheels and during their operational employment are presented in a generalized form. Contact teeth destruction as the main cause of failures of high-speed gear wheels in well-lubricated enclosed gears are considered. The causes of the wearing and sticking of the teeth along their lateral surfaces as well as scoring and destruction depending on the origin of the cracks are revealed.
The main causes of damaging and destruction of helicopter reduction trains, locations and origination of fatigue cracks spots are identified. Different types of contact and fatigue destructions due to various reasons are considered.
Dynamic loading of gear wheels disks as a result of their rotation damages the material of the wheels in the area of multi-cycle fatigue due to the repeatability of flight load cycles.
Lamination or deep contact destruction of the material, which sometimes take place in gears with surface hardened (cemented, tempered, nitrided, etc.) teeth, are much more dangerous than surface destruction of the material since sufficiently large fractions of the hardened material layer are split away from the teeth that can quickly break down an entire gear train.
The main causes of contact teeth destruction are load concentration along the length and profile of the teeth, the presence of residual tensile stresses on the working surfaces of the teeth, adverse operational damage to the tooth profiles and negative effect of lubricating fluid on the teeth.
For a repaired gear train the cause of the uneven load distribution along the length of the teeth may be the poor assembly of the gear wheels and other transmission parts which leads to unsatisfactory contact of the gear teeth in the assembled unit.
The revealed peculiarities of the destruction process indicate regular crack proliferation from flight to flight. According to the operation conditions of the gear wheel, its regular extensive loading refers only to the full cycle of starting and stopping the reducer train or unloading the helicopter in flight, which in this case corresponds to the cycle of helicopter operation in one flight. Therefore, the number of detected fatigue lines corresponds to the number of helicopter flights.
To increase the smoothness of gear train running which affects positioning accuracy, reduce wear during running-in, decrease noise, eliminate early jamming, and ultimately, to increase the resource, it is necessary to eliminate the edge interaction of the teeth, which causes their excessive wear.
5
Pilipenko, O., D. Kolesnik, A. Berezniak i V. Shokha. "DAMAGING AND DESTRUCTION OF REDUCTION TRAINS OF MI-8 HELICPTER AND ITS MODIFICATIONS". Наукові праці Державного науково-дослідного інституту випробувань і сертифікації озброєння та військової техніки, nr 4 (19.08.2020): 92–106. http://dx.doi.org/10.37701/dndivsovt.4.2020.11.
Pełny tekst źródłaStreszczenie:
The results of quantitative factographic study of the Mi-8 helicopter (its modifications) reduction trains with different types of gear coupling, the destruction of which occurred while in flight due to the presence of preliminary material damage at the stage of production of the gear wheels and during their operational employment are presented in a generalized form. Contact teeth destruction as the main cause of failures of high-speed gear wheels in well-lubricated enclosed gears are considered. The causes of the wearing and sticking of the teeth along their lateral surfaces as well as scoring and destruction depending on the origin of the cracks are revealed.
The main causes of damaging and destruction of helicopter reduction trains, locations and origination of fatigue cracks spots are identified. Different types of contact and fatigue destructions due to various reasons are considered.
Dynamic loading of gear wheels disks as a result of their rotation damages the material of the wheels in the area of multi-cycle fatigue due to the repeatability of flight load cycles.
Lamination or deep contact destruction of the material, which sometimes take place in gears with surface hardened (cemented, tempered, nitrided, etc.) teeth, are much more dangerous than surface destruction of the material since sufficiently large fractions of the hardened material layer are split away from the teeth that can quickly break down an entire gear train.
The main causes of contact teeth destruction are load concentration along the length and profile of the teeth, the presence of residual tensile stresses on the working surfaces of the teeth, adverse operational damage to the tooth profiles and negative effect of lubricating fluid on the teeth.
For a repaired gear train the cause of the uneven load distribution along the length of the teeth may be the poor assembly of the gear wheels and other transmission parts which leads to unsatisfactory contact of the gear teeth in the assembled unit.
The revealed peculiarities of the destruction process indicate regular crack proliferation from flight to flight. According to the operation conditions of the gear weel, its regular extensive loading refers only to the full cycle of starting and stopping the reducer train or unloading the helicopter in flight, which in this case corresponds to the cycle of helicopter operation in one flight. Therefore, the number of detected fatigue lines corresponds to the number of helicopter flights.
To increase the smoothness of gear train running which affects positioning accuracy, reduce wear during running-in, decrease noise, eliminate early jamming, and ultimately, to increase the resource, it is necessary to eliminate the edge interaction of the teeth, which causes their excessive wear.
6
Pavelko, Vitalijs, Eric Ozolinsh, Ilmars Ozolinsh i Sergey Kuznetsov. "INVESTIGATION OF DYNAMIC STRESSES OF TAIL BEAM OF AN MI-8 HELICOPTER/SRAIGTASPARNIO MI-8 GALINĖS SIJOS DINAMINIŲ ĮTEMPIMŲ TYRIMAS". Aviation 12, nr 4 (31.12.2008): 118–23. http://dx.doi.org/10.3846/1648-7788.2008.12.118-123.
Pełny tekst źródłaStreszczenie:
Results of theoretical and experimental research of stresses in the skin of a tail beam of an Mi‐8 helicopter at resonant dynamic loading are discussed in this paper. It is shown that resonant tests of the object with an appropriate choice of configuration of internal and external constraints are one of the most effective and economical ways to achieve the necessary result. It is also obvious that the choice of a configuration for the complex dynamic system should be solved on the basis of a careful preliminary analysis of expected dynamic properties. First of all, the research that was performed shows the very significant effect of the elasticity of internal and external constraints on the dynamic properties of real aircraft components at full‐scale dynamic testing. On other hand, it is shown that the correct modelling of a complex elastic system and its constraints allows one to adequately describe the dynamic properties of the real structure and to obtain good coincidence with experimental data. Santrauka Straipsnio tikslas – ištirti ribinių sąlygų įtaką nominaliems įtempimams atskirose plonasienės sijos vietose ir parinkti racionalų dinaminės apkrovos režimą planuojant realų eksperimentą. Nominalūs įtempimai įvertinti pagal sijos dinaminių charakteristikų analizės rezultatus koncentruotų masių metodu. Buvo modeliuojamos neklasikinės ribinės sąlygos, kurios tiksliau apibūdina realius sijos ryšius. Įvertinant sijos įtvirtinimo elastingumą ir vidinių ryšių elastingumą galima gauti tikslesnes laisvųjų svyravimų pirmųjų dviejų dažnių reikšmes, kurios gerai sutampa su bandymų rezultatais. Kaip rodo analizė, vidinių ir išorinių ryšių elastingumas turi didelę įtaką sijos dinaminėms charakteristikoms, tarp jų ir laisvųjų svyravimų formai ir dažniui.
7
Stojanovic, Ivica. "Measuring noise and vibration in the cockpit of the Mi-8 helicopter". Vojnotehnicki glasnik 64, nr 1 (2016): 176–95. http://dx.doi.org/10.5937/vojtehg64-7714.
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Berezniak, A., Т. Dudnik i O. Zakutko. "THE MAIN TEST RESULTS OF THE MI-2MSB HELICOPTER EQUIPPED WITH THE EXPERIMENTAL SYSTEM OF SMALL ARMS AND SERIES-PRODUCED SYSTEM OF UNGUIDED MISSILE ARMAMENT". Наукові праці Державного науково-дослідного інституту випробувань і сертифікації озброєння та військової техніки, nr 6 (30.12.2020): 26–32. http://dx.doi.org/10.37701/dndivsovt.6.2020.03.
Pełny tekst źródłaStreszczenie:
The summarized results of special tests of the Mi-2MSB helicopter equipped with the experimental system of 12,7 mm small arms (as a part with series-produced machine guns NSVT-12,7) and the serial system of unguided missile armament (NAR type C-8) are presented. The actual volume of assessments of inspections and work performed during the tests is given.
According to the results of processing the test materials, it was determined that the tactical range of the Mi-2MSB helicopter with the installed weapons system and boxes for collecting spent units (in the design provided for testing) at a takeoff mass of 3700 kg, at an altitude of not more than 300 m during combat mission in the area of the target for 5 minutes and the remaining fuel on the landing of 100 liters is (not less):
version of combat equipment 2 × B8V8MSB (payload - 16 NAR) - 190 km;
version of combat equipment 2 × NSVT-12.7 (payload - 600 rounds) - 200 km;
version of combat equipment 2 × B8V8MSB + 2 × NSVT-12.7 (payload - 16 NAR and 600 rounds) - 155
The results of special tests practically showed that the Mi-2MSB helicopter, equipped with an aviation weapon system, in addition to the functional tasks defined for the basic Mi-2MSB helicopter, is able to provide:
training and maintenance of skills for flight crew in the practical application of unguided aviation weapons and gun armaments in all types of maneuvering, defined by the tactics of army aviation;
accomplishment of certain tasks on air support of columns of troops on the march and fire missions on destruction of enemy manpower, single unarmored and lightly armored targets such as car, armored personnel carrier, infantry fighting vehicle, boat,
The main combat and functional capabilities in the actual operating conditions confirmed by the results of special tests as well as their validation of specified requirements make it possible (after eliminating the shortcomings identified in the test), to allow operation of Mi-2MSB helicopter in the entire operating range of heights and speeds equipped with aircraft weapons as part of the unguided missile system (NAR type C-8) and small arms system (as part of the series-produced machine guns NSVT-12.7)).
9
Akimov, O., V. Dmytriiev, V. Boiarov i V. Fedenko. "SIMULATION OF NATURAL OSCILLATIONS OF THE AIR ASSAULT RAPPELLING SYSTEM “KANAT-1”". Наукові праці Державного науково-дослідного інституту випробувань і сертифікації озброєння та військової техніки, nr 8 (29.06.2021): 4–9. http://dx.doi.org/10.37701/dndivsovt.8.2021.01.
Pełny tekst źródłaStreszczenie:
The main purpose of the article is to consider the simulation of the natural oscillations of the air assault rappelling system “Kanat-1”.
The object of consideration is a set of removable onboard equipment for rappelling air assault "Kanat-1" for landing from the cargo hatch of Mi-8 helicopters.
Air assault rappelling system is an oscillating system that has certain natural frequencies of oscillation of the item, which depend on the number of paratroopers on the rope and their placement on it. The airframe of the Mi-8 helicopter has its own frequencies within the ranges of 3.1 - 3.3; 8 - 9; 15 - 17 Hz with which, and their divisibles the natural frequencies of the item should not coincide. In real operating conditions, determining the natural frequencies of the elements of the item under load is problematic.
A system of dynamic models is built which allows determining the natural frequencies of air assault rappelling system oscillations at arbitrary placement of up to three paratroopers weighing up to 140 kg each, which can be hung simultaneously on one of the ropes in constant motion while moving the points of contact with the rope. In general, at the maximum load on the rope (three paratroopers), the mathematical model represents a system of three second-order differential equations. Eight variants for loading the rope with paratroopers are considered. The obtained oscillation frequencies of the air assault rappelling system do not coincide with the oscillation frequencies of the helicopter airframe which proves the effectivity of the air assault rappelling system.
Recommendations for regulation of frequency characteristics of air assault rappelling system by replacement of a fastening element of a rope to a traverse are developed.
10
Messingerová, V., i J. Tajboš. "Exposition of working and natural environment to noise during timber transport by helicopter MIL MI-8 in Carpathian region of Slovakia". Research in Agricultural Engineering 53, No. 3 (7.01.2008): 103–10. http://dx.doi.org/10.17221/2127-rae.
Pełny tekst źródłaStreszczenie:
This paper includes the results of noise measurements during timber transport by helicopter MI-8 in The High Tatras conditions in 2005. Using this highly efficient timber skidding technology with multiple positive environmental properties causes an unwanted effect – air-traffic noise. The objective of this paper is to quantify the level of noise effect for two correlated groups; noise effecting workers and noise effecting environment. The highest values measured in the worst conditions reached 90–100 dB (A).
11
Kinaschuk, Mykhailo. "NUMERICAL STUDY OF THE EXHAUST GAS FLOW OF TV3-117 TYPE ENGINES IN COMPOSITION WITH A SCREEN - EXHAUST DEVICE". ScienceRise 4 (31.08.2020): 17–23. http://dx.doi.org/10.21303/2313-8416.2020.001391.
Pełny tekst źródłaStreszczenie:
The object of research is a screen-exhaust device in the TV3-117 engine of the Mi-8 helicopter. Investigated problem: The problem of equalizing the flow in the exhaust nozzle is solved. As a result of the numerical study, the total pressure losses are calculated and the flow structures in the structural elements of the exhaust nozzle and the screen-exhaust device (SED) are analyzed. Main scientific results: Obtained Gas-dynamic parameters of the flow in the SED flow path are obtained and the verification of injection processes between the working circuits along the path in the SED design is done. Numerical modeling of gas flows in the SED flow path makes it possible to study in detail the characteristics of the flow at any of its points, as well as to determine the values of hydrodynamic losses associated with the formation of a boundary layer and the emergence of separation zones. A constructive method for leveling the gas-dynamic flow is proposed by installing a blade in the form of an aerodynamic profile in a standard engine exhaust nozzle. Two variants of engine nozzles are investigated under the same boundary conditions using a standard exhaust nozzle with and without a blade. The influence of uneven flow in the exhaust nozzle on the nature of the flow in the SED is shown. An insignificant equalization of the flow in the exhaust nozzle using the installed blade led to a decrease in the total pressure loss in the SED by more than 1 %. The area of practical use of the research results: The results of calculations and modeling can be used for computational and experimental studies aimed at improving the flow path of the exhaust nozzle and the screen-exhaust device by the developers of new military aviation equipment or when modernizing the existing helicopter fleet. Scope of application of the innovative technological product: a new screen-exhaust device has been proposed for left and right TV3-117 engines of all types, which can be installed on the Mi-8MSB-V, Mi-8MT, Mi-14, Mi-24 helicopters. It is competitive and has significantly higher technical and economic indicators compared to known analogues.
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Гребеников, А. Г., И. В. Малков, В. А. Урбанович, Н. И. Москаленко i Д. С. Колодийчик. "КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ ОСОБЛИВОСТІ ХВОСТО-ВИХ БАЛОК СІТЧАСТОГО ТИПУ З ПОЛІМЕРНИХ КОМПО-ЗИЦІЙНИХ МАТЕРІАЛІВ ВЕРТОЛЬОТІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ". Open Information and Computer Integrated Technologies, nr 88 (6.11.2020): 15–30. http://dx.doi.org/10.32620/oikit.2020.88.02.
Pełny tekst źródłaStreszczenie:
The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.
13
Rakonjac, Veljko, i Zoran Filipovic. "Vibration and flight data measurement on the transport helicopter Mi-8 with replaced main rotor blades". Vojnotehnicki glasnik 52, nr 6 (2004): 611–21. http://dx.doi.org/10.5937/vojtehg0406611r.
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Vorobev, E. N., V. I. Veremyev i D. V. Kholodnyak. "RECOGNITION OF PROPELLER-DRIVEN AIRCRAFT IN A PASSIVE BISTATIC RADAR". Journal of the Russian Universities. Radioelectronics, nr 6 (18.01.2019): 75–90. http://dx.doi.org/10.32603/1993-8985-2018-21-6-75-82.
Pełny tekst źródłaStreszczenie:
Nowadays passive bistatic radars (PBR) allow for detection, determination of coordinates and tracking of moving objects. In order to enable PBR integration into air traffic control systems, it is necessary to solve the problem of recognizing airborne objects, in particular, propeller-driven aircraft (AC). This will increase the degree of aviation safety. To solve the recognition problem, the analysis of propeller-driven aircraft echo signals, such as helicopter and propeller airplane, is performed. The in-formative features that can be used for recognition of propeller-driven aircraft in PBRs are defined. The method for propeller-driven aircraft recognition is proposed, that is based on extraction of modulation components originated from the rotational parts of the aircraft and estimation of their rotation parameters. The algorithm for echo signal processing is developed, which makes it possible to apply the proposed recognition method for PBRs. The experimental results of the processing algorithm are presented on the example of real signals reflected from the Mi- 8 helicopter and the Cessna 172 propeller aircraft. The experimental data are recorded by two different PBRs using DVB-T2 digital terrestrial television signals standard for airspace illumination. The estimated rotation parameters of the aircraft propeller blades correspond to the actual values. Such a correspondence allows not only to recognize the aircraft group, but in some cases to identify its type.
15
Tatarchuk, T., Yu Kravchuk i V. Pelykh. "Use of additive technologies in the manufacture of central impactors". Innovative Materials and Technologies in Metallurgy and Mechanical Engineering, nr 1 (14.09.2021): 47–53. http://dx.doi.org/10.15588/1607-6885-2021-2-8.
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Purpose. Analysis of methods of manufacturing centrifugal blades by 3D printing methods on the example of a modernized cooling system of the AI-450M engine of the Mi-2MSB helicopter.
Research methods: calculation method of finite elements, analytical.
Results. Studies have shown that the use of layer-by-layer printing technology of the centrifugal wheel of the cooling system provides the following opportunities and improvements:
- reduce the percentage of rejection of finished products by 8–9 times;
- reduce material consumption by 300–400 %;
- increase the speed of production, experiments and testing the manufacture of working elements through the development of new technologies for rapid production (rapid fabrication);
- easy printing of previously “impossible” geometry.
The analysis of possible types of manufacturing of working centrifugal wheel and the calculated estimation of thermodynamic parameters in the course of step-by-step drawing of layers of metal is carried out. The problem of a large percentage of defects in the process of classical-mechanical milling of blades was solved by changing the type of production to additive one.
Scientific novelty. In today's world, the spread of CAD / CAM / CAE / PLM technologies and the accumulation of a wide library of materials open up a large number of new and more efficient, in terms of economy and quality, methods of manufacturing components and units. Following the example of such giants in the production of aircraft engines as Rolls-Royce Motor, General Electric and Pratt & Whitney, it is clear that the use and development of the latest methods of three-dimensional printing is appropriate.
Practical value. The obtained results are important in the further process of production and modernization ofMi-2 helicopter of all modifications with the latest engines, as well as for projects for the development of helicopter construction in Ukraine - МСБ-2 “Hope”, МСБ -6 “Otaman”, МСБ-8 and others. The ability to increase the efficiency of manufacturing the main working elements - blades allows you to reduce the cost of components, their further repair, operation. The most important factor is to increase reliability, as in the manufacture reduces the likelihood of defects, which will not be detected at the stages of intermediate and final control.
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Borisov, Yu A., P. N. Rybkin i Yu M. Chinyuchin. "Information technologies-the basis of training, retraining and advanced training systems for helicopter pilots". Civil Aviation High Technologies 22, nr 6 (26.12.2019): 112–24. http://dx.doi.org/10.26467/2079-0619-2019-22-6-112-124.
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In the early 90s there was a need for the complex development of training, retraining, maintaining and professional development system designed for the most popular Mi-8 helicopter pilots oriented at modern information technologies. The system covers all the stages of pilot training, starting with the initial stages of professional activity up to its completion. The technical means compiling specifications for the whole range training were determined by the results of the pilot in-flight activity analysis. The proposed optimal range of technical facilities for training consists of technical means with different levels of out-of-cockpit and in-cockpit environment simulation. The utilization of these means allows to minimize the expenditures on proficiency level support and cost of pilot training. The set of technical training appliances such as: automated training courses of theoretical disciplines, computer functional and situational simulators, navigation simulators and flight complex simulator includes the facilities that provide training of the pilot actions at each stage of the flight. The individual schedule of computer based self-development classes is drawn up for each student. While compiling the individual schedule logical sequence of all training stages was carefully observed: firstly we begin with a thorough study of helicopter structure, then goes the study of functional system or equipment normal operation, functional system or equipment in special situations operation, and finally, the routine technology of crew operation in normal flight conditions and the crew actions in dangerous and emergency situations. In addition to the direct training of students, the initial stage of training solved the tasks of practical check and improvement of previously taken decisions.
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Beecken, J., J. Mellqvist, K. Salo, J. Ekholm, J. P. Jalkanen, L. Johansson, V. Litvinenko, K. Volodin i D. A. Frank-Kamenetsky. "Emission factors of SO<sub>2</sub>, NO<sub>x</sub> and particles from ships in Neva Bay from ground-based and helicopter-borne measurements and AIS-based modeling". Atmospheric Chemistry and Physics Discussions 14, nr 19 (16.10.2014): 25931–65. http://dx.doi.org/10.5194/acpd-14-25931-2014.
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Abstract. Emission factors of SO2, NOx and size distributed particle numbers were measured for approximately 300 different ships in the Gulf of Finland and Neva Bay area during two campaigns in August/September 2011 and June/July 2012. The measurements were carried out from a harbor vessel and from an MI-8 helicopter downwind of passing ships. Other measurements were carried out from shore sites near the island of Kronstadt and along the river Neva in the city area of Saint Petersburg. Most ships were running at reduced speed (10 knots), i.e. not at their optimal load. Vessels for domestic and international shipping were monitored. It was seen that the distribution of the SO2 emission factors is bi-modal with averages of 4.6 gSO2 kgfuel−1 and 18.2 gSO2 kgfuel−1 for the lower and the higher mode, respectively. The emission factors show compliance with the 1% fuel sulfur content SECA limit for 90% of the vessels in 2011 and 97% in 2012. The distribution of the NOx emission factor is mono-modal with an average of 58 gNOx kgfuel−1. The corresponding emission related to the generated power yields an average of 12.1 gNOx kWh−1. The distribution of the emission factors for particulate number shows that nearly 90% of all particles in the 5.6 nm to 10 μm size range were below 70 nm in diameter. The distribution of the corresponding emission factors for the mass indicates two separated main modes, one for particles between 30 and 300 nm the other above 2 μm. The average particle emission factors were found to be in the range from 0.7 to 2.7 × 1016 particles kgfuel−1 and 0.2 to 3.4 gPM kgfuel−1, respectively. The NOx and particulate emissions are comparable with other studies. The measured emission factors were compared, for individual ships, to modeled ones using the Ship Traffic Emission Assessment Model (STEAM) of the Finnish Meteorological Institute. A reasonably good agreement for gaseous sulfur and nitrogen emissions can be seen for ships in international traffic, but significant deviations are found for inland vessels. Considering particulate mass, the modeled data is about two to three times above the measured results, which probably reflects the assumptions made in the modeled fuel sulfur content. The sulfur contents in the fuel retrieved from the measurements were lower than the previously used assumptions by the city of Saint Petersburg when carrying out atmospheric modeling and using these measurements it was possible to better assess the impact of shipping on air quality.
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Beecken, J., J. Mellqvist, K. Salo, J. Ekholm, J. P. Jalkanen, L. Johansson, V. Litvinenko, K. Volodin i D. A. Frank-Kamenetsky. "Emission factors of SO<sub>2</sub>, NO<sub><i>x</i></sub> and particles from ships in Neva Bay from ground-based and helicopter-borne measurements and AIS-based modeling". Atmospheric Chemistry and Physics 15, nr 9 (11.05.2015): 5229–41. http://dx.doi.org/10.5194/acp-15-5229-2015.
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Abstract. Emission factors of SO2, NOx and size-distributed particle numbers were measured for approximately 300 different ships in the Gulf of Finland and Neva Bay area during two campaigns in August/September 2011 and June/July 2012. The measurements were carried out from a harbor vessel and from an Mi-8 helicopter downwind of passing ships. Other measurements were carried out from shore sites near the island of Kronstadt and along the Neva River in the urban area of Saint Petersburg. Most ships were running at reduced speed (10 kn), i.e., not at their optimal load. Vessels for domestic and international shipping were monitored. It was seen that the distribution of the SO2 emission factors is bi-modal, with averages of 4.6 and 18.2 gSO2 kgfuel-1 for the lower and the higher mode, respectively. The emission factors show compliance with the 1% fuel sulfur content Sulfur Emission Control Areas (SECA) limit for 90% of the vessels in 2011 and 97% in 2012. The distribution of the NOx emission factor is mono-modal, with an average of 58 gNOx kgfuel-1. The corresponding emission related to the generated power yields an average of 12.1 gNOx kWh−1. The distribution of the emission factors for particulate number shows that nearly 90% of all particles in the 5.6 nm to 10 μm size range were below 70 nm in diameter. The distribution of the corresponding emission factors for the mass indicates two separated main modes, one for particles between 30 and 300 nm and the other for above 2 μm. The average particle emission factors were found to be in the range from 0.7 to 2.7 × 1016 particles kgfuel-1 and 0.2 to 3.4 gPM kgfuel-1, respectively. The NOx and particulate emissions are comparable with other studies. The measured emission factors were compared, for individual ships, to modeled ones using the Ship Traffic Emission Assessment Model (STEAM) of the Finnish Meteorological Institute. A reasonably good agreement for gaseous sulfur and nitrogen emissions can be seen for ships in international traffic, but significant deviations are found for inland vessels. Regarding particulate mass, the values of the modeled data are about 2–3 times higher than the measured results, which probably reflects the assumptions made in the modeled fuel sulfur content. The sulfur contents in the fuel retrieved from the measurements were lower than the previously used assumptions by the City of Saint Petersburg when carrying out atmospheric modeling, and using these measurements it was possible to better assess the impact of shipping on air quality.
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Kharitonov, VV. "Hygienic Characteristics of the Acoustic Environment in the Mi-8 Helicopter Cabin". ЗДОРОВЬЕ НАСЕЛЕНИЯ И СРЕДА ОБИТАНИЯ - ЗНиСО / PUBLIC HEALTH AND LIFE ENVIRONMENT, luty 2021, 54–61. http://dx.doi.org/10.35627/2219-5238/2021-335-2-54-61.
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Introduction: The Mi-8 helicopter generates high-intensity broadband noises by its turboshaft engines whereas a comprehensive hygienic assessment of the acoustic environment in the helicopter cabin has not been conducted. The purpose of the study was to assess the acoustic environment in the Mi-8 helicopter cabin. Materials and methods: Acoustic measurements were carried out on the ground, inside the central cabin of the Mi-8 helicopter in three operating modes of the turboshaft engines: at startup, in the idle mode, and during cruise flight in the “right correction” mode. Measuring microphones were placed during the recording of the signal on a stand at the level of the human ear at six points located next to the reclining seats in the cabin. Acoustic indicators were measured using an SVAN-945A digital sound level meter and a GRAS 40AZ microphone. The collected data were processed in accordance with the requirements of sanitary and epidemiological rules, sanitary standards, and general tactical and technical requirements of the Air Force. Results: Values of regulated noise indicators at the seats of the Mi-8 helicopter crew, sound pressure levels of the most significant tonal frequencies in its central compartment were measured. To establish the presence of tonal noise, a one-third octave analysis of the recorded acoustic signals was carried out. In the central compartment of the helicopter, the values of the regulated infrasound indices and the general sound pressure level were measured in the entire regulated frequency range. Discussion: It was found that the sound pressure levels in almost all sound octaves and the equivalent sound level in all operating modes of the helicopter engines exceed the permissible exposure limits while in the infrasound region they are within the normal range (except for the frequency of 16 Hz). Thus, the class of working conditions by noise corresponds to hazard class 3.3, and by infrasound – to class 2. According to the sanitary regulations, helicopter crews should use noise suppressors to protect themselves from high noise exposures through air and bone conduction. Conclusion: The existing risks of developing a noise and infrasound-induced diseases necessitate constant monitoring of working conditions and health of the crews of Mi-8 helicopters.
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Блохин, Л. Н., В. Г. Вовк i Ю. Н. Безкоровайный. "The Task of Identification of Parameters of the Helicopter Mi-8 with a Cargo in a Mode of Lag Above the Land". Problems of Informatization and Management 1, nr 10 (1.03.2004). http://dx.doi.org/10.18372/2073-4751.1.11369.
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Богоявленский, А., A. Bogoyavlenskiy, А. Боков i A. Bokov. "Bench equipment for maintenance OF mi-8, MI-17 helicopters and its metrological research". World of measurement, 25.12.2015, 12–20. http://dx.doi.org/10.35400/1813-8667-2015-04-12-20.
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In recent years, there has been a positive trend in the domestic air transport for the modernization of bench equipment used in organizations for maintenance and repair of aircraft. The peculiarity of the introduction of this kind of equipment is the confirmation of compliance of the actual values of its technical (and, first of all, metrological) characteristics when setting (maintaining) modes of maintenance and repair of aircraft to the normalized values specified in the technological maps of the maintenance regulations and repair technologies.