Annotation: The technique is proposed of reliability evaluation of space launch vehicle low pressure air thermostating system joints hoses. By calculation method, high reliability level was confirmed of hoses of joints being an interface elements of launch vehicle launch complexes.

Annotation: The article deals with the problems of applying new approaches to formation and improvement of operation system. Turning of space hardware and services into marketable commodity requires their new qualities that determine competitiveness. The main task of presented works was approbation of new approaches to improvement of space launch systems operation quality and operation process effectiveness by the example of prospective Cyclone-4M space rocket complex. The works to form and improve its operation system were performed using the methods based on general theory of space systems operation and the pocedures based on the results of research work conducted by Yuzhnoye SDO in 2015 for analytical evaluation of launch services costs. The topicality of the article is confirmed by the results of practical application of new approaches in main directions of Cyclone-4M space rocket complex operation system improvement, which allowed increasing commercial attractibility of Yuzhnoye SDO-developed systems due to reduction of direct recurring costs and annual expenses. The article describes the course of development of operation model of a created object; based on investigation of the processes of this model, the object’s performance characteristics are detemined. The basis of the article are the organizational-and-technical decisions used herewith and the results obtained for Cyclone-4M space rocket complex. The article is of practical interest for specialists involved in creation of space rocket complexes and other sophisticated systems where the operation system is a multi-level organizational-technical system.

Annotation: Due to an increase of power of rocket engines, the high intensity sound field generated by the exhaust jets have become an important factor, which determines the success rate of a rocket launch. Ensuring a successful launch of a rocket system became harder due to new engineering problems. Identification and definition of acoustic sources structure within a complex supersonic jet, being a one of the most important scientific problems, which have to be solved to find the ways to control accoustic radiation. A three components of acoustic sources can be defined here – broadband signals from large and small components of of turbulent jet and tonal signals which usually being overlooked during the estimation of overall sound pressure level. The paper considers various aspects of acoustics of the launch of rocket systems, which includes characteristics of acoustic sources in supersonic jets, possibilities and physical limitation factors, under which it is possible to control the sound radiation. Among the possible ways to control the process of sound generation by a jet, a method of water injection in a jet is being studied. While saving the general thrust of the engine this method can not greatly reduce the sound radiation by a jet. It is recommended to use big amounts of water-air mix to protect the launch pad from damage. Significant progress on the topic of understanding the process of sound generation by supersonic jets can be achieved via mathematical modeling of sound radiation. The latest achievements of mathematical modeling of sound generation by supersonic jets being presented.

Annotation: Being a final executive element of rocket control systems, a hydraulic actuator is at the same time the main source of various non-linear dependencies in rocket dynamic design whose availability dramatically com plicates theoretical analysis of their dynamics and control systems synthesis. The required accuracy and complexity of mathematical models of hydraulic servo mechanisms are different for different design phases of guided rockets. The paper deals with the simplest models of hydraulic servo actuators intended to calculate rocket controllability and to define requirements to response and power characteristics of the actuators. To calculate the rocket stability regions and to evaluate own stability of servo actuators, a linearized mathematical model of hydraulic servo actuator is used that takes into account the most important parameters having impact on stability of the servo actuator itself and on that of the rocket: hardness of working fluid, stiffness of elastic suspension of the actuator and control element, slope of mechanical characteristic of the actuator in the area of small control signals, which, as full mathematical model analysis showed, is conditioned only by dimensions of initial axial clearances of slide’s throats. The full mathematical model constructed based on accurate calculations of the balance of fluid flow rate through the slide’s throats allows, as early as at designing phase, determining the values of most important static and dynamic characteristics of a future hydraulic actuator, selecting optimal characteristics of slides based on specified degree of stability and response of servo actuator and conducting final modeling of rocket flight on the integrated control system test benches without using real actuators and loading stands. It is correct and universal for all phases of rockets and their control systems designing and testing. Using this mathematical model, the powerful actuators of a line of intercontinental ballistic missiles with swinging reentry vehicle and the main engines actuators of Zenit launch vehicle first stage were developed. The results of their testing separately and in rockets practically fully comply with the data of theoretical calculations.

Annotation: The mathematic modeling was performed of the flight of light-class three-stage launch vehicle injecting a payload into sun-synchronous orbit of 700 km altitude and a cluster of observed space debris objects in the conditions of dynamically changing cataloged space situation. It is shown that as the launch moment becomes closer, the cataloged space situation is ascertained, which leads to the constant change of the quantity of hazardous space debris objects observed in the vicinity of launch vehicle trajectory and to the change of the parameters of their approach to the launch vehicle: minimal relative distance, relative velocity, rendezvous angle and launch moment for which hazardous approach is revealed. The hazardous approaches for the launch vehicle trajectory under consideration are more often observed with the relative velocities of more than 8 km/s and rendezvous angles less than 90 deg and their variations within the launch window do not exceed 1.2 m/s and 0.035 deg respectively. In this case, the histograms of distribution of relative distance, relative velocity, and rendezvous angle from catalog to catalog vary insignificantly. The distribution of hazardous approaches in launch time within launch window is not uniform, the regions are observed with low quantity of hazardous approaches and with high quantity. The hazard of launch vehicle collision with observed space debris objects in a launch is confirmed. In all, in the launch day time window under consideration, more than ten hazardous approaches are revealed, for two of them the approach to minimal distance of less than 1 km is predicted. This testifies to the necessity of taking measures to increase safety of launch vehicle flight through observed space debris cluster. In order to increase Ukrainian launch vehicles miss ion safety in the conditions of near space pollution, it is proposed to create the system of pre -flight space analysis, whose tasks are periodic analysis of space situation not less than once in a day, revealing of hazardous approaches, determination of their parameters, and preparation of data to make decision on launch time.

Annotation: The shell structures widely used in space rocket hardware feature, along with decided advantage in the form of optimal combination of mass and strength, inhomogeneities of different nature: structural (different thicknesses, availability of reinforcements, cuts-holes et al.) and technological (presence of defects arising in manufacturing process or during storage, transportation and unforseen thermomechanical effects). The above factors are concentrators of stress and strain state and can lead to early destruction of structural elements. Their different parts are deformed according to their program and are characterized by different levels of stress and strain state. Taking into consideration plasticity and creeping of material, to determine stress and strain state, the approach is effective where the calculation is divided into phases; in each phase the parameters are entered that characterize the deformations of plasticity and creeping: additional loads in the equations of equilibrium or in boundary conditions, additional deformations or variable parameters of elasticity (elasticity modulus and Poisson ratio). Then the schemes of successive approximations are constructed: in each phase, the problem of elasticity theory is solved with entering of the above parameters. The problems of determining the lifetime of space launch vehicles and launching facilities should be noted separately, as it is connected with damages that arise at alternating-sign thermomechanical loads of high intensity. The main approach in lifetime determination is one that is based on the theory of low-cycle and high-cycle fatigue. Plasticity and creeping of material are the fundamental factors in lifetime substantiation. The article deals with various aspects of solving the problem of strength and stability of space rocket objects with consideration for the impact of plasticity and creeping deformations.

Annotation: For monitoring rocket flight and determining accuracy of spacecraft injection into the planned orbit, it is necessary to ensure the reception of telemetry data from the launch vehicle. Telemetry data receiving stations may be located either on land or on shipboard. When the antenna system of such station is placed on shipboard, ship roll and ship drift have the most considerable impact on the antenna guidance accuracy. To ensure the guidance accuracy of the telemetry receiving antenna set, placed on shipboard, the control algorithm was designed. It was offered to use triaxial rotary support with axis of reflector inclination angle to meet the requirements specified. In the article, the connection between kinematic parameters of the antenna rotary support drives and parameters of the space launch vehicle motion were identified, rotation angles of the antenna drives along the three axes were determined, and the law of angular velocity variation along the azimuthal axis, including the maximum feasible angular velocity provided by the azimuthal axis drive, was chosen. Numerical simulation of antenna guidance algorithms that provide stable signal receiving under conditions of ship roll was carried out in the visual development environment of Embarcadero RAD Studio XE6. Several variants for operation of the rotary support drives of the antenna set were chosen for mathematical simulation; disturbing conditions of ship roll and ship drift were analyzed and chosen for ships with small displacement. The simulation validated the designed antenna control algorithm and showed that the requirements for the cinematic parameters of the antenna drives were reduced under conditions of ship roll when the axis of reflector inclination angle was introduced; and accelerometer unit or GPS receiver installed in the antenna structure additionally increased the accuracy of target designation of the antenna and improved its guidance accuracy

Annotation: One of the tasks of the development tests conducted on a launch pad is verification of its strength properties. The tests are carried out after the launch pad was manufactured and assembled on-site as well as during the whole operating period (if necessary). Load mode was chosen in consideration of cost and possibility of providing the required loading conditions. Two modes of creating the required test load were examined: usage of weights with corresponding mass (load simulators) or special devises (which have smaller mass as compared with load simulators). The descriptions, basic characteristics, advantages and disadvantages of composite and bulk weights and pad loading device are given. This article studies the pad loading device under development. This device enables to conduct static nondestructive tests on the launch pad in order to check its strength after manufacturing and during the whole operating period. The device consists of the load-bearing frame, hydraulic system, locks, control system and measurement system. Advantages of the pad loading device include low materials consumption, low cost in comparison with composite weights (with large load values), provision of the required modes for applying and removing the test load, controlled separate loading of each support of the launch pad, high mobility, short duration of testing, possibility of using launch pads of other rocket complexes with lower or equal test load values for testing. Therefore, the pad loading device enables to achieve the required test load values while having considerably smaller dimensions and mass as compared with composite weights and bigger functional possibilities as compared with bulk weights. Small overall dimensions and operability reduce the number of needed personnel and equipment.

Annotation: The measurement errors upon conducting flight tests for launch vehicles are evaluated by considering the interferences and uncertainties in the measurement system procedure. Formal use of this approach can lead to unpredictable consequences. More reliable evaluation of errors upon conducted measurements can be achieved if the measurement process is regarded as a procedure of successive activities for designing, manufacturing, and testing the measurement system and the rocket including measurements and their processing during the after-flight analysis of the received data. The sampling rates of the main controlled parameters are three to ten times higher than the frequency range of their changing. Therefore, it is possible to determine the characteristics of the random error components directly on the basis of registered data. The unrevealed systematic components create the basic uncertainty in the evaluation of the examined parameter’s total measurement error. To evaluate the precision and measurement accuracy of a particular launch, the article suggests specifying the preliminary data on measurement error components determined during prelaunch processing and launch. Basic structures of algorithms for evaluation of precision and measurement accuracy for certain mathematical models that form the measured parameters were considered along with the practical case when static correlation existed among the measured parameters.

Annotation: Basic dynamic properties of the reentry part of the aircraft-type first stage were examined when turbojet engine is used in the recovery phase. Such configuration can be of interest because turbojets have considerably smaller rate of flow in comparison to rocket engines. Moreover, they are launched in the lower stratosphere or in the troposphere so that there is no need to place oxidizer supply on board. This recovery plan differs from an alternative rocket recovery system and, from our point of view, provides more efficient usage of the fuel stores because it doesn’t require the main propulsion to be started in the recovery phase. Besides the analysis of qualitative characteristics of the descend phase for this stage, the efficiency of a wing with moderate values of maximum aerodynamic characteristics and a turbojet was studied. In this case three ways for stage recovery were investigated. The first one implied unguided descend with zero angle of attack assuming that the stage is statically stable. This descend trajectory was considered as standard and was used to evaluate the efficiency of the wing and turbojet with relatively small propulsion. The second and the third design cases offered the gliding guided descend with turbojet being started only in the lower stratosphere. The last two cases used the same program for the angle of attack. The possibility to ensure permissible overload values at the critical points of the descend trajectory and acceptable values of kinematic characteristics at the earth surface tangency point are also of great interest. Thereby the program for the angle of attack was developed in a way that allowed kinematic characteristics on touchdown be as close as possible to the corresponding values, shown by civil and/or military-transport heavy aircraft. Simulation was conducted on Microsoft Visual Studio 2010.