The research is focused on the development of an Unmanned Aircraft System. One of the design process steps in the preliminary design phase is the calculation of the flight envelope for the Unmanned Aircraft System air vehicle. The results obtained will be used in the further design process. A flight envelope determines the minimum requirements for the object in Certification Specifications. The present situation does not impose any Certification Specification requirements for the class of the Unmanned Aircraft System under the development of the general European Union trend defined in the road map for the implementation of the Unmanned Aircraft System. However, operation in common European Aerospace imposes the necessity for regulations for micro class systems as well.
Aleksandrs Urbahs, Konstantīns Savkovs, Gints Rijkuris and Darja Andrejeva
Corrosion is one of the most common naturally occurring processes studied by thermodynamics, which includes oxidation process, metal disruption, and its chemical and electrochemical effects under environmental influence. Corrosion of metal and equipment accounts for a considerable proportion of total corrosion losses, thus providing the impetus for further investigation and developments related to corrosion protection in order to provide transport systems and industry with corrosion preventive materials and tools.
S. Sakthivelu, M. Meignanamoorthy, M. Ravichandran and P. P. Sethusundaram
This research made an attempt to synthesize aluminum metal matrix composites through stir casting technique. The matrix material chosen in this study was AA7050 and the reinforcement material was ZrSiO4. The composites AA7050, AA7050-10%ZrSiO4, and AA7050-15%ZrSiO4 were used. The wear behavior of the aluminum matrix composites was investigated by using pin-on-disc tribometer. The advanced material has substantial development in tribological behavior when the reinforcement percentage is increased. From the experimental results, it was confirmed that sliding distance of 1200 m, applied load of 3 N and sliding speed of 2 m/s result in minimum wear loss and coefficient of friction, while adding 10%ZrSiO4 to the AA7050.
The aim of this article is the development of the system and methodology of complex control and evaluation of vehicle operators performance during multifunctional simulation. In order to achieve the above-stated aim it is necessary to solve the following principal tasks: to elaborate a theoretical model of differentiated evaluation of vehicle operator training degree according to different kinds of their functional performance; to develop the method of the differential evaluation of crew performance on full-scale aviation simulators with due consideration of the probabilistic approach on the basis of statistical processing of the data of recorded flight information. The offered theoretical model of the differential evaluation of operator performance and the methodology of standards determination developed on its basis represent a new approach to the creation of automated systems for the objective evaluation of the trainees’ qualification degree. The elaborated system of differential evaluation standards ensures a high degree of objectiveness when evaluating the degree of the vehicle operator qualification and makes it possible to carry out a comparative analysis of the operators’ qualification.
Andrzej Ambrozik, Dariusz Kurczyński and Piotr Łagowski
Modern means of transport are basically powered by piston internal combustion engines. Increasingly rigorous demands are placed on IC engines in order to minimise the detrimental impact they have on the natural environment. That stimulates the development of research on piston internal combustion engines. The research involves experimental and theoretical investigations carried out using computer technologies. While being filled, the cylinder is considered to be an open thermodynamic system, in which non-stationary processes occur. To make calculations of thermodynamic parameters of the engine operating cycle, based on the comparison of cycles, it is necessary to know the mean constant value of cylinder pressure throughout this process. Because of the character of in-cylinder pressure pattern and difficulties in pressure experimental determination, in the present paper, a novel method for the determination of this quantity was presented. In the new approach, the iteration method was used. In the method developed for determining the volumetric efficiency, the following equations were employed: the law of conservation of the amount of substance, the first law of thermodynamics for open system, dependences for changes in the cylinder volume vs. the crankshaft rotation angle, and the state equation. The results of calculations performed with this method were validated by means of experimental investigations carried out for a selected engine at the engine test bench. A satisfactory congruence of computational and experimental results as regards determining the volumetric efficiency was obtained. The method for determining the volumetric efficiency presented in the paper can be used to investigate the processes taking place in the cylinder of an IC engine.
Aleksandrs Urbahs, Kristīne Carjova, Aleksejs Nasibullins and Dmitry Nedelko
 A. Lingelli, Fatigue Crack Growth: Mechanics, Behavior and Prediction. New York, USA: Nova Science Publishers Inc., 2009. ISBN 978-1-60692-476-1
 A. Urbahs, K. Carjova, J. Fescuks and I. Stelpa, “Development of Theoretical Model for Aircraft Structural Health Monitoring by Acoustic Emission Method,” in Mechanika 2015: Proceedings of the 20th International Conference, Kaunas, Lithuania: Kaunas University of Technology, 23-24 April, 2015, pp. 262-267. ISSN 1822-2951
 A. Urbahs, K. Carjova, A
Andris Vaivads, Jevgēnijs Tereščenko and Vladimirs Šestakovs
. Riga Aeronautical Institute, 017, pp. 5-11. ISBN 9789984999654
 V. Šestakovs, “Airplanes Incidents Analysis Because of Aviation Personnel and Evaluating the Effectiveness of Measures to Prevent Accident,” in Problems of Maintenance of Sustainable Technological Systems: Vol. 5, Sustainable Development of Transport. Kielce, Kielce University of Technology, 2012. pp. 111-125. ISBN 9788388906749
 A. Vaivads, N. Dreimanis, and V. Šestakovs, “Pilota kļūdas analīze,” in 49th International Scientific Conference of RTU, Riga, Latvia
Ruta Bogdane, Aleksandrs Bitiņš, Vladimirs Šestakovs and Yasaratne Bandara Dissanayake
, “Evaluation of Management System Effectiveness in the Preparation of the Aircraft for Flight in Faulty Conditions,” Transport and Aerospace Engineering, vol. 2, no. 1, Jan. 2015. https://doi.org/10.1515/tae-2015-0002
 J. H. Weiss and M. E. Gershon, Production and Operations management. Boston: Allyn and Bacon, 1993.
 R. Bogdane, V. Šestakovs, and D. Dencic. “Development of the Mathematical Model of Integrated Management System for an Airline,” Transport and Aerospace Engineering, vol. 3., no. 1, pp. 44-51, Jan. 2016. ISSN 2255968X. e
 Yu. Paramonov and A. Kuznetsov, “Planning of inspections of fatigue-prone airframe,” Ultrasound, vol. 59, no. 2, pp. 59-64, 2006. ISSN 1392-2114
 Yu. Paramonov and M. Hauka, Minimax decision for reliability of aircraft fleet and airline. Seventh International Workshop on Simulation Book of Abstracts University of Bologna, Italy, 21-25 May, 2013.
 Yu. Paramonov and A. Paramonova, “Inspection program development by the use of approval test results,” International Journal of Reliability, Quality and Safety Engineering, vol. 7
Aleksandrs Urbahs, Margarita Urbaha and Kristīne Carjova
 A. Betz, Introduction to the Theory of Flow Machines , D. G. Randall, Trans. Oxford: Pergamon Press, 1966.
 Intergovernmental panel on climate change, IPCC Special Report on Emissions Scenarios , 2015. [Online]. Available: http://www.grida.no
 A. Urbahs, M. Urbaha, and K. Carjova, “Development and Assessment of Planetary Gear Unit for Experimental Prototype of Vertical Axis Wind Turbine,” Latvian Journal of Physics and Technical sciences , vol. 54, no. 5, 2017. https://doi.org/10.1515/lpts-2017-0033
 E. M