Annotation: During 60 years of existence of specialized Liquid Rocket Engines Design Office – DO-4 as a part of Yuzhnoye Design Office, extensive experience was accumulated in development of liquid rocket engines of various purpose on storable and cryogenic propellant components. The required test benches and production base were created. When developing the engines, the DO-4 specialists widely use the experience accumulated during manufacturing and testing of the engines developed by the other design offices for Yuzhnoye SDO LVs that were manufactured by SE PA Yuzhny Machine-Building Plant and tested at Yuzhnoye SDO’s and Plant’s test benches. Along with the conventional ones, new original engine designs were developed to achieve high energy-mass characteristics, reliability and quality. Among them we should mention the RD858 and RD859 engines for the soviet lunar take-off-and –landing module of Block E, the unique RD857 and RD862 engines with afterburning of reducing generator gas and gas dynamic method of thrust vector control, the RD866 multifunctional engine of space tug ensuring multiple ignition in flight, and many others. At present, Yuzhnoye SDO jointly with SE PA Yuzhny Machine-Building Plant deliver the engine for the European Vega LV forth stage propulsion system under the contract with Avio company (Italy). Based on Yuzhnoye SDO–created engines, propulsions systems for ballistic missiles and space rockets that are unique by their characteristics and scope of functions, the engines, propulsions systems for spacecraft, LV upper stages and transfer orbit stages can be developed in short terms and at minimal costs.

Annotation: The results of work are described to determine optimal materials for one of the elements of middle position lock to increase load bearing characteristics and contact resistance of the middle position lock. The results are presented of experimental check of impact of material of rod with hydraulic actuator piston on contact resistance and load capacity of the middle position lock of thrust vector control system two-channel hydraulic actuator. As replacer, the 18ХГТ steel was selected allowing (after carbonization and hardening) obtaining in surface layer of material the HRCэ 56-62 hardness with plastic core, instead of HRCэ 36-42 after hardening of applied 09Х16Н4Б steel. The comparative results were obtained in the tests of experimental sample of the lock completed with two rods with piston: the rod with piston manufactured according to DD and the experimental rod with piston that passed carbonization to the depth 0.9-1.3 mm and hardened to HRCэ 56-62. The rod’s ring groove – one of the elements of lock was subjected to carbonization and hardening. Both rods with piston were tested in the lock’s dummy in the load range: up to 1200 kgf –standard rod with piston and up to 3000 kgf – experimental rod with piston under static and cyclic loading. The test results are positive: the standard rod with piston confirmed its serviceability at the loads up to 1200 kgf inclusive; the experimental rod with piston withstood the loads up to 3000 kgf under static and cyclic loading. The evaluation of contact resistance was made by comparison of dimensions of traces left by the balls on the surface of rod’s grove under lock loading. The dimensions of traces on the experimental rod with piston under the load 3000 kgf inclusive did not exceed the dimensions of traces on the standard rod with piston, which testifies to the increase of contact resistance. We believe that the direction of search for steel brands in combination with advanced methods of thermal treatment is promising in increasing the lock’s load-bearing characteristics.

Annotation: This article considers the problem of determination of propulsion system solid fuel burn-out time in the extraatmospheric flight segment taking the apparent acceleration and apparent speed measured by the inertial navigation system. Correlation analysis of the realized and nominal dependencies of the apparent acceleration and apparent speed of the launch vehicle on relative operating time of the propulsion system is suggested to be used to forecast the fuel burn-out time. In order to improve the accuracy of the forecast, and to decrease the amplitude and vibration rate of its results several channels simultaneously are suggested to be used for calculations with subsequent majority voting and digital filtration. As a result of the study, the procedure to forecast the time of solid fuel burn-out in the launch vehicle propulsion system in flight has been developed. Operability of the suggested procedure has been verified using the mathematical simulation of the launch vehicle flight for two operating modes of the propulsion system different from the nominal ones. Based on the statistical processing of the deviations of the predicted time of solid fuel burn-out versus the realized one it was determined that the forecast based on the results of apparent acceleration measurement has the greatest accuracy with the minimal number of operations. Suggested procedure is easily realized as the multistage adaptive algorithm and can be used in the guidance system of the solid-propellant launch vehicle in the extra-atmospheric flight segment for the numerical forecast of the reachable terminal parameters of flight, definition of command vector and development of the relevant thrust vector control commands.