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This work examines the most promising design solutions for the creation of propulsion systems for ultra-light launch vehicles by small private enterprises in the rocket and space industry. Comparison of the metal consumption of the combustion chambers with the energy characteristics at different operating pressures showed that the most optimal operating pressure is 12,16 MPa. Comparison of the relative and absolute values of the masses of various configurations describes the nature of the relationship between the number of combustion chambers and the total mass of the propulsion system. It was found that nine-chamber propulsion systems with cameras made with extensive use of additive technologies best meet the key requirements. The analysis carried out includes an assessment of the design parameters of both various components and assemblies and the propulsion system as a whole. Various layouts of propulsion systems are considered in detail, the required degree of technological complexity of structures of various units and assemblies, their production cost are estimated. The ratio of the obtained mass-energy characteristics was achieved through the implementation of design solutions that became available due to the use of additive technologies. The obtained results of preliminary calculations demonstrate the applicability and efficiency of design solutions considered for use in the propelled propulsion system for a promising launch vehicle.

Knee osteoarthritis (OA) and varicose disease of the lower extremities (VD) are two diseases common in middle– aged and older women. Questions about whether their combination is accidental or natural and whether VD affects the course and severity of OA, remain unresolved.The aim of the study was to look for the possible association between knee OA and lower limb vein pathology on the basis of clinical and modern instrumental investigation sand to study the effect of the VD on the clinical manifestations and severity of knee OA.Materials and methods. A case-control study was conducted in 85 women 40–60 years old with knee OA diagnosed in accordance with the criteria of ACR (1986) and 50 women of the same age without signs of knee OA. Women of both groups were evaluated for complaints and objective examination with an emphasis on diseases of the joints and veins of the lower extremities, radiography of the knee joints, ultrasound duplex scanning of the veins of the lower extremities. The severity of OA was assessed by the Lequenne indices. The clinical assessment of venous pathology was carried out according to the CEAP classification.Results. Patients with knee OA more often than their peers without joint pathology have VD (43% vs 22%; p=0.015), signs of chronic venous insufficiency (28% vs 12%; p=0.03), as well as valve failure of several lower limb veins simultaneously (53% vs 20%; p=0.0004). After correction by body mass index, the association of knee OA with detected vascular pathology remained clinically and statistically significant. The presence of VD with moderate manifestations of chronic venous insufficiency, as well as ultrasound signs of venous pathology, was not associated with the clinical signs and course of knee OA.Conclusions. Knee OA in middle-aged and older women, regardless of body mass index, is associated with VD and ultrasound signs of simultaneous valves failure of several veins. Manifestations of chronic venous insufficiency did not affect the clinical picture and severity of knee OA.