Operation features of aviation tankers in the conditions of the Far North
Authors: Savushkin S. A. , Balyshin K. E. , Kozlov A. N. , Brailko A. A. 
Published: November 2023

Huge territories of the Russian Federation are occupied by permafrost. Often aviation is the only mode of transport that connects remote north areas of the country with the rest of Russia. The main feature of permafrost regions is the harsh climate, which includes low negative temperatures, an abundance of snow and strong winds. Such conditions make it extremely difficult to operate ground vehicles that service and maintain flights. In recent years, more and more domestic tankers have been exhausting their life span. At present, a significant number of northern refueling complexes have switched to the operation of foreign tankers based on Volvo and Mercedes-Benz tractors. The operation of these vehicles has already revealed a series of shortcomings which extremely complicate the normal procedures. There is an acute need to refine the components and assemblies in order to reduce the failures that affect the regularity and safety of aircraft flights. One of the main problems of fuel tankers operation at low temperatures is the malfunction of the electropneumatic bottom valve, due to its freezing. The paper proposed replacing this problematic node with a mechanical bottom valve, which is not susceptible to low temperatures. In order to avoid cracking of rubber products of the underwing refueling nozzle and to increase the flexibility of the dispensing hoses, it is proposed to carry out heating of the glass of the refueling nozzle and the filling module by means of exhaust gas bypass and pumping hot coolant through the system of nozzles. The most serious problems are the difficulties of operating a diesel-powered tractor at low temperatures. Problems arise already at startup. Diesel fuel at low subzero temperatures can thicken or even solidify, the lubricant also thickens. There have been cases when the startup was complicated by low compression in the cylinders. But even if the engine was able to start, after a while it may start to stall. This is due to oxygen starvation, which occurs because the icy air entrains water, which is deposited as frost on the air filters, thereby blocking the oxygen supply to the engine. After prolonged parking at low temperatures, during the first seconds of starting the piston engine, the parts come into contact with each other without lubrication. The reason is the viscosity of the oil which decreases at extremely low temperatures, therefore, in order for the lubricant to reach the end users through narrow oil pipelines, it takes some time to warm up (about 10 minutes). As a result of such cold starts and the risk of bullying on the parts of the piston group, their durability is reduced by more than 40%. When starting cold, the engine additionally warms up itself at higher idle speeds. To prevent undesirable consequences, as well as to create more favorable conditions for starting the diesel unit, reducing fuel consumption, it is proposed to use a pre-heater with an external power source from the 220 V electrical network. In order to facilitate the start of the diesel engine, it is necessary to provide the heating of the fuel line and fuel pump filters. To eliminate oxygen starvation of the engine, due to the formation of frost on the filter elements, and to increase the stability of the engine, it is necessary to provide the heating of the air filter.