Climatic conditions of the territory where the road is located (air temperature, solar radiation) influence the "work" of asphalt concrete pavements. The influence causes shear deformations at high positive temperatures and the occurrence of cracks at low negative temperatures. In the late 80s, in the USA the asphalt pavement design system Superpave (Superior Performing Asphalt Pavements) defined the temperature limits of pavement "work". The Performance Grade parameter has been introduced associated with the choice of bitumen. Based on the long-term climatic data the temperature limits have been determined for the territory of the Republic of Belarus.

This paper presents the initial study results of the process of crack appearance in asphalt pavements by reason of traffic load and temperature. Calculations were carried out using of finite element method. According to the modeling results appearance of reflected cracks under the traffic load and cracks that occurred under the influence of temperature were predicted. Recommendations on the choice of the road structure are also presented in the paper.

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The fuel for civil aviation jet engines is aviation kerosene. In the fuel systems of aircraft and aircraft engines, they perform a number of functions, one of the main ones being the lubricating function. The lubricity of fuels depends on many factors, including the technologies for their production, which are constantly changing. The lubricity of Russian fuels for civil aviation is not standardized and not controlled. A comparative assessment of the lubricity of fuel brands used in civil aviation on a four-ball friction machine is shown in the article. The introducing an indicator characterizing the lubricity of fuels into the Russian standard for jet fuels relevance is justified.

Current trends of civil aviation development show a significant increase in the number of aircraft with aircraft piston engines. The Ministry of Transport of the Russian Federation is preparing a draft order on amendments to the Federal aviation rules for the preparation and performance of flights in civil aviation (FAP-128), which stipulate for simplified procedures of paid excursion flights implementation for light and ultralight aircraft and helicopters. It is obvious that this circumstance will significantly affect the expansion of the fleet of these aircraft. Accordingly, the state of piston engines operating on aviation gasoline value questions are becoming increasingly relevant. The current problems of aviation engines diagnostics by metal contents in oils are observed in the article. Their bugs, possible ways of solving this problems and bugs, actual developments in this direction are shown. The application examples of early diagnostic methods using the automated diagnostic complex “Prisma” are shown. The oil samples taken from An-2 aircraft АШ-62ИР piston engine analyses results attract the most interest. They show that with proper training of personnel the valuable information coming from the oil samples can be a source of important conclusions not only in aircraft engines accessories and assemblies state value, but also others systems, and also conclusions about the quality of fuel and lubricants used. Estimating the residual life method of the engine at various stages of its operating time on the metal content in the oils and the procedure for oil selecting, allowing to obtain reliable results, are suggested.