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Open access

Ēriks Ozoliņš, Ilmārs Ozoliņš and Līga Ramāna

Abstract

The article describes the impact of the gas turbine engine low-pressure turbine blade shroud shelf on the blade profile stress position. Attention is focused directly on the impact of the location of the gravity centre of the shroud shelf on blade stress distribution at the three most critical points of the profile. The paper describes the details of the calculation and the required expressions provided, as well as the results of the calculation example with clear graphical dependencies.

Open access

Andrii Grekhov, Vasil Kondratiuk and Svitlana Ilnitska

Abstract

Original models of RPAS communication channels based on IEEE 802.11b Standard, including both Base Station transmission within the Radio Line of Sight, and through the satellite using Beyond Radio Line of Sight, were built. Dependencies of the Bit Error Rate on the Signal-Noise Ratio for different payload data rates were obtained. Transponder nonlinearity and Base Station antenna diameter impact were analysed.

Open access

Juris Maklakovs, Jevgēnijs Tereščenko and Vladimirs Šestakovs

Abstract

In the field of security in transport distinguish risks related to flight safety and aviation security. Safety of flights is ensured through the reliability of aviation equipment and the qualification of the personnel who services and operates it, aviation security is a condition of protection from illegal interference in its activity. Risk management in civil aviation in the field of security is a relatively new direction of activity. Deep research in this area began only at the beginning of the XXI century. It is quite difficult to use the existing experience of risk management, accumulated in other spheres, as civil aviation has significant features. Various methods and schemes can be used to assess risks. The article discusses various options for predicting risks using the “event tree” and “risk factor tree” methods.

Open access

Dmitrijs Goreļikovs, Margarita Urbaha, Dmitry Nedelko and Jonas Stankunas

Abstract

Electronic Chart Display and Information Systems (ECDIS), which are used on vessels and can replace paper charts, allow to obtain and display on electronic charts information from basic and additional data sources. For the certified use of ECDIS instead of paper charts, it is necessary to ensure constant updating of Electronic Navigation Chart (ENC) data provided to vessels for use. The known visual and satellite observation systems intended for cartographic information update are costly, have low accuracy and do not allow to quickly update navigational charts in real-time mode. The stand-alone use of remotely piloted aircraft (RPA) will make it possible not only to substantially reduce costs and increase the accuracy of monitoring, but also to provide information in real-time mode.

Open access

Ilmārs Ozoliņš, Ēriks Ozoliņš and Valērija Fedotova

Abstract

The paper presents a method of calculation gas turbine engine compressor or low-pressure turbine working blade profile for student training. This method of calculation was prepared for working blades with and without shroud shelves. This method provides a calculation technique to reduce the load on blade root part and the determination of blade profile stress distribution and the comparison before and after reduction of load.

Open access

Pjotrs Trifonovs-Bogdanovs and Anvar Zabirov

Abstract

Analysis and simulation of the Strapdown Inertial Navigation System (SINS) error genesis revealed that the East Feedback Contour has the greatest influence on the development of an error in this model, and angular velocity sensor Δω𝒚 is the critical element. In order to prevent the development of an error, structural correction in the East Feedback Contour, and elements that are more critical, namely in angular velocity measurement sensors is the best option.

Open access

Deniss Brodņevs

Abstract

Remotely piloted operations of lightweight Unmanned Air Vehicles (UAV) are limited by transmitter power consumption and are always restricted to Line-of-Sight (LOS) distance. The use of mobile cellular network data transfer services (e.g. 3G HSPA and LTE) as well as long-range terrestrial links (e.g. LoraWAN) makes it possible to significantly extend the operation range of the remotely piloted UAV. This paper describes the development of a long-range communication solution for the UAV telemetry system. The proposed solution is based on (but not restricted to) cellular data transfer service and is implemented on Raspberry Pi under Gentoo Linux control. The goal of the project is to develop a flexible system for implementing optimized redundant network solutions for the Non-LOS remote control of the UAV

Open access

Andris Vaivads, Jevgēnijs Tereščenko and Vladimirs Šestakovs

Abstract

The article presents a semiotic model of “aircraft conditions” in flight and multilevel structures of an aircraft. The hierarchical structure of abstract models is divided into blocks and levels that make them more compact by applying a mathematical apparatus corresponding to the goals sated. The above models were tested on the basis of statistical data on TU-154 aircraft failures for 10 years. Various aircraft functional system failures in flight were examined. The state of the aircraft is identified by normative indicators recorded in the “Aircraft Technical Operation Manual”.

Open access

Olga Girvica

Abstract

This paper deals with the problem of optimal resource distribution in optimal way among the units of an aviation company. This task could be solved by using the method of dynamic programming. Using Mathcad 14 programming language, there was created a special program that allows to make corresponding calculations. The solution of the real task for an aviation company is observed in this paper as a numerical sample of limited resource distribution between the units of the company in order to get the maximum profit.

Open access

Ruta Bogdane, Aleksandrs Bitiņš, Vladimirs Šestakovs and Yasaratne Bandara Dissanayake

Abstract

In this article, the authors offer a methodology for determining the quality of airline performance by taking into account the level of flight safety on the basis of factor analysis and the results of methodology approbation in the conditions of a functioning airline. The assessment of the level of airline performance quality taking into account the level of flight safety within a certain time span is rather sensitive, informative and reliable. They allow us to detect those changes in industrial and economic conditions and factors that are related to a certain degree of potential deterioration of flight safety. This creates conditions for revealing the tendencies towards the deterioration of flight safety at the stage of their origin, when they have not yet caused deep, irreversible changes in the flight safety of an airline.