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Motivated by a computer experiment for the design of a rocket booster, this article explores nonstationary modeling methodologies that couple stationary Gaussian processes with treed partitioning. Partitioning is a simple but effective method for dealing with nonstationarity. The methodological developments and statistical computing details that make this approach efficient are described in detail. In addition to providing an analysis of the rocket booster simulator, we show that our approach is effective in other arenas as well.

It is examined if any limitations in existing solid rocket propellant grain manufacturing methods adversely affected the payload capability of recent space launch vehicles. It is seen if the transition from heavy, segmented metal rocket motor casings to lightweight monolith composite casings is possible without loss of ability to design and realize high-performance grain configurations using simple and safe methods. Considering payload fraction as the comparative performance metric, recently flown solid rocket-propelled, small-lift launch vehicles were surveyed and ranked. Solid rocket boosters of underperforming launch vehicles were investigated for manufacturing factors influencing payload fraction by comparing them to boosters of better-performing launch vehicles in their weight class. Relationships between payload fraction and the solid boosters’ mass fractions, casing construction, shape of thrust profile, propellant grain configuration and method employed to manufacture the grain were analysed. It is shown that those launch vehicles that did not possess or use the technology necessary to manufacture high-performance grain configurations like undercut finocyl in monolith composite casings ended up having boosters delivering poor thrust profiles with high inert mass ultimately leading to low payload fractions.

Grand lauching of UAV is a potential technology which will greatly improve effectiveness and application rang of UAV. Rocket booster grand lauching is a technology which has a high degree of difficulty and multiple influence factors. Chimera mesh method and relevant CFD method are applied to ensure the successful performance of 6DOF motion body simulations of booster rocket separation phase so that aerodynamic characteristics of UAV and booster rocket in the separation phase can be revealed. The error and precision of the simulations are then analyzed and conclusions concerning UAV aeroforce and moment variation are drawn. Finally, the feasibility and safety of separantion design in this thesis are testified.

The paper deals with the design of a two-stage to orbit rocket launcher loaded with a solid rocket booster, scramjet, and hybrid rocket for delivering a 100kg payload in 200 km circular orbit. The possibility of implementing a cavity-based axisymmetric circular combustor in a scramjet is proposed. Computational analysis on various injector locations in a circular combustor and their validation with the test bench results were performed. The utilisation of a hybrid rocket in the final stage of the launcher to deliver the payload is discussed and the performance characteristics of the circular scramjet combustor and the hybrid rocket are shown. The overall mission proposed based on the sustainable and reusable characteristics.

The Apophis fly-by highlights how much astronomers have learnt about near-Earth asteroids - and how much they still have to learn. Since 1998, when NASA kicked off the biggest search for near-Earth asteroids, scientists have detected more than 25,000 of them. The finds included an object named 2020 SO, which turned out to be not an asteroid, but a leftover rocket booster that had been looping around in space since it helped to launch a NASA mission to the Moon in 1966. All of these discoveries are making astronomers more aware of the billiard-ball nature of the Solar System, where plenty of asteroids ping around in the space near Earth.

Advanced space launch vehicles that employ solid rocket boosters are found to use undercut finocyl-shaped propellant grains. The undercut features, however, cannot be easily manufactured using conventional methods of casting propellant around rigid monolith mandrels or by machining the fin slots. To solve the problem, many non-rigid type mandrels were experimented with without wide acceptance due to functional, performance, or safety issues. Alternatively, in recent times, a few types of rigid undercut finocyl grain mandrels have been developed by different space agencies. While each claims superior performance, there has been no study measuring or quantifying their relative performance. The purpose of this study was to evaluate and compare the assembly performance of a new mandrel called ‘NEX’ using Design for Assembly (DFA) tools against state-of-the-art Vega mandrels employed in the making of some of the largest and highest-performing solid boosters worldwide. Mandrel parts and their assembly sequences were reconstructed using patent literature and published data. Boothroyd-Dewhurst DFA Product Simplification software was used for analyzing both mandrels and quantifying the difficulty of total assembly and disassembly. It is found that in comparison with Vega, NEX has 60 % fewer part counts, 80 % fewer fastener activities, and 41 % reduced assembly man-hours. The estimated DFA index for Vega is 3.57 and NEX is 5.78. Using the newer and safer mandrel, space launch vehicle booster manufacturing costs can be lowered.

Most conventional missiles and rocket boosters use solid propellant systems based on ammonium perchlorate (AP). However, combustion of AP during rocket launch produces toxic chloride emissions that increase in air pollution by 1 %. Researchers and engineers have developed several methods for transforming conventional AP-based propellant into green propellant, which is suitable for use in environmentally friendly rocket engines. These include neutralising, non-chlorine and scavenging propellants. The current study is aimed at investigating the properties ofa neutralising propellant using various metal additives, including aluminium (Al), magnesium (Mg) and lithium (Li). Theoretical research has demonstrated that the addition of metal additives reduces the level of toxic hydrochloric acid (HCl) without compromising performance. By utilising the Rocket Propulsion Analysis (RPA) software with input on pressure conditions ranging from 100 to 2,000 psi, a simulation study of HCl reduction in propellant combustion products and ballistic performance was conducted. Pure metal additives of Mg with 15 % composition significantly increased the specific impulse (Isp) of solid propellant based on pure ammonium perchlorate /hydroxyl-terminatedpolybutadiene (AP /HTPB) by 24 % and the value of characteristic velocity (c) by 22 %. Observations on the HCl reduction of APbased propellant samples utilising rocket propulsion thermodynamics analysis indicate that adding Li15 % to the basic propellant increases the HCl reduction by 99 %. Therefore, lithium metal mixtures in AP / HTPB-based solid propellant resulted in greater reduction of HCl mole fraction, whereas aluminium metal compositions resulted in superior ballistic performance.

We report the results of radar observations of a near-Earth object discovered on 17 September 2020, with the Pan-STARRS 1 telescope at the Haleakala Observatory in Hawaii. Initially, this object was considered an asteroid and even received the standard provisional designation 2020 SO by the Minor Planet Center. However, its Earth-like orbit and low relative velocity suggested that the object may be of artificial origin, being the Centaur rocket booster from the Surveyor 2 mission that was launched to the Moon on 20 September 1966. In the period from November 2020 to March 2021, this object approached the Earth twice within one lunar distance of the Earth. Radar observations were conducted on 30 November in bistatic mode with the 70-m Goldstone Solar System Radar DSS-14 and 32-m radio telescope RT-32 at the Svetloe Observatory, while the object was in the visibility window of two antennas at about 200 thousand km from the Earth. The main goal of the study was to determine the physical properties of this object using radar astronomy to clarify its origin.

For increasing understanding of fundamental hypersonic phenomena, the flight test program, named MF-1, is to gather fundamental scientific and engineering data on the physics and technologies critical to future operational hypersonic flight with low-cost flight test platform, which is built on the retrofitted rockets. The MF-1 program is a hypersonic flight test program executed by China Aerodynamic Research and Development Center (CARDC). The MF-1 flight flew in December 2015. The flight focuses primarily on integration of instrumentation on the test vehicle, with application to boundary layer transition and shock interaction experiments. The MF-1 payload consists of a blunted 7°half angle cone, a cylinder and 33° flare configuration. The payload was boosted to Mach 5.32 utilizing a solid-rocket booster without control for the whole flight. The flight was fully successful, and measured transition under supersonic and hypersonic conditions. The heat flux data were given by the three-dimensional thermal identification method to discriminate transition zone. The preliminary analysis shows that the real-time flight data obtained by MF-1 are reliable and can be used to validate the transition predicting model and software. The results show that the existing model is able to predict the transition location of cone at a small angle-of-attack for supersonic or hypersonic flow. This paper describes the MF-1 mission and some general conclusions derived from the experiment.