The paper presents the data obtained in the course of experimental studies on the production of rods from the Al-0.5% REM alloy using combined processing methods, such as combined rolling-extruding (CRE) and combined casting and rolling-extruding (CCRE). The variable parameters were the temperature of the ingot or melt, the degree of deformation and the strain rate. With the help of strain gauge equipment, experimental data were obtained on the forces acting on the rolls and the die of the CCRE-200 combined processing unit in the process of obtaining rods with a diameter of 5 and 9 mm. The estimation of the dependence of the mechanical properties of the rods on the variable factors has been carried out. The highest strength properties are possessed by a bar obtained by the CRE mode at a temperature T = 550 oC and a strain rate ξ = 0.74 s-1. When comparing the temperature of pouring the metal, the highest strength properties are possessed by a rod with a diameter of 9 mm and 5 mm and a strain rate ξ = 0.74 s-1. If compare in terms of the deformation rate, then the highest strength properties are possessed by a rod with a diameter of 5 mm and a deformation rate ξ = 1.49 s-1. The plasticity of deformed semi-finished products in all modes is at a high level, which allows further processing.

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An orbital flight with long pauses between sustainer engine starts calls for engine starts in space, for which purpose the presence of the propellant at the feed line inlet must be assured. Since with the sustainer engine switched off the propellant is in nearly zero gravity and can move freely throughout the tank occupying almost any spatial position, the propellant must be moved to its pre-start position to assure a guaranteed restart of the sustainer engine. The propellant is moved to the feed lines by setting up a longitudinal acceleration using thrusters. The time it takes for the whole of the propellant to be moved from one position to the other is the most important parameter that affects the propellant amount and thus the stage energy characteristics. This paper considers fuel settlement in the fuel tank of a launch vehicle's third stage with the use of two thrusters before a sustainer engine restart in the worst case where the whole of the remaining fuel is concentrated near the upper pole of the tank, which corresponds to the maximum distance to be traveled by the fuel and thus to the maximum settlement time. The paper presents the authors' calculation and experiment method for determining the propellant settlement time, which combines an experimental study and a numerical simulation of propellant settlement, thus allowing one to conduct the necessary studies with a desired accuracy and significantly reduce the extent of testing and the need for material facilities. The proposed method will make it possible to optimize the traditional procedure of settlement time calculation by assuring a more accurate determination of the settlement time as early as at the initial stage of development, thus reducing the volume of the propellant components required for the thruster operation with a corresponding increase in the payload mass.