SpaceX's SuperHeavy Starship interstellar transportation system project is developing rapidly and has now entered the orbital-level test flight stage, which may become another powerful launch vehicle to change the world's aerospace landscape. The different stages of the design iteration of the SuperHeavy Starship system are sorted out. The main technical changes and improvement motivations in each stage are summarized. The technical characteristics and the future application direction of SuperHeavy Starship are analyzed. It is hoped to provide enlightenment for the development of China's space launch vehicles.

For solid-engine aircraft, closed-loop guidance methods with energy matching or angle constraints are generally used in the powered flight segment, which have high control accuracy. However, its accuracy is greatly affected by engine performance deviations. Therefore, a zero-range Orientation closed-loop guidance method based on neural network is proposed to reduce the impact of engine performance deviation on the guidance accuracy. Firstly, the motion model of the powered flight segment of the aircraft is established, and the closed-loop guidance of the zero-range Orientation is analyzed and deduced. Secondly, a multi-input neural network algorithm is designed, the input and output parameters are determined, the residual energy, the velocityto be increased and the angle of the zero-range Orientation are trained. Then, the training results of the above neural network with the zero-range Orientation closed-loop guidance are combined. This method enables feedback of different zero-range Orientation angles under different engine deviations. Finally, different deviation states for simulation verification are chosen. The simulation results show that this method can effectively reduce the influence of engine deviation on the guidance accuracy, and has strong anti-bias ability and high guidance accuracy.

Mobile Launcher (ML) is one of the critical ground supporting systems, which is going to be in service for Space Launch System (SLS). The function of ML includes stacking, assembly, process checkouts and launch support for the SLS rocket and Orion spacecraft. The structure layouts, operations and functions from Apollo and Saturn V are valued and baselined. The ground support equipment like umbilicals and accessories are researched and renewed. Besides, ML is aimed to be possessed of strong applicability and generality for different heavy-lift rockets, including SLS. The generality design is then performed, and modules and equipment are borrowed from previous launchers. Comprehensive tests of function, security and reliability are carried on. The research in the paper will provide reference for the launcher of heavy-lift rocket in China.

Thermal protection is a regional protection measure covering the outer surface of the launch pad to prevent the bearing structure of the launch pad from being eroded by the rocket launch gas flow. It is a key link to ensure that the launch pad can reliably carry the rocket safely. In recent years, as the launch frequency of the conventional liquid carrier rocket represented by the Long March 2C rocket has increased year by year, the recovery time of the launch pad after the launch of the rocket has also been greatly reduced. Therefore, a rapid recovery scheme for thermal protection of the launch pad is proposed, which combines the ablation type heat protection technology with the absorption type heat protection technology, and the modular thermal protection components are designed to realize rapid replacement through simulation, test and use. The results show that the repair time of the new thermal protection is shortened from 3 days to 1 day, and the protection effect is good, which can meet the needs of high-density rocket launch.

C/SiC composite material for hypersonic vehicle structure has a broad application in near-space area. The active / passive ablation performance of the C/SiC composite is studied numerically. An approach for active sublimation ablation performance up the ${2000}^{\circ}\mathrm{C}$ of $\mathrm{C}/\mathrm{{SiC}}$ composite materials is proposed and some wind tunnel experiments have been designed and completed. The results show that the ablation performance proposed has good accuracy compared with the wind tunnel results. The results can provide a reference for the structure and thermal protection design and safety assessment of the hypersonic vehicles based on C/SiC composite material.

Aiming at solving the SBIRS three satellites detection trajectory estimation problem, a data fusion trajectory estimation algorithm based on the GEO satellite and the HEO satellite detection is proposed. According to the SBIRS constellation composition and detection mechanism, the STK is used to analyze the SBIRS coverage capability to a certain area, calculation shows that over three satellites can fully cover it in about 43% of the simulation time. Establishing the three satellites detection data fusion estimation algorithm model to estimate the missile target motion state in real time, the current statistical model is adopted to describe the missile motion state, the centralized structure is adopted to achieve detection data fusion, in addition, the unscented Kalman filter is used as trajectory estimation filter. Simulation results show that, compared with the binary detection trajectory estimation error, the three satellites detection trajectory estimation error is significantly reduced.

In order to enhance the delivery and survival capability of unmanned aerial vehicle group in specific areas in long-range mission scenarios, and effectively complete various missions, a missile borne unmanned aerial vehicle group delivery scheme is proposed. The unmanned aerial vehicle group is delivered to the mission area through missile carriers, utilizing the rapid reentry advantage of the missile to improve the delivery and survival capability of the missile borne unmanned aerial vehicle group. Taking the end interception system "Dense Array" as a scenario, the survival capability of the unmanned aerial vehicle group is simulated and analyzed under two schemes of missile based delivery and parachute based delivery. The effectiveness of the proposed scheme is verified, meeting the requirement of the unmanned aerial vehicle group entering the mission area with a high survival probability in actual mission scenarios.

This article focuses on the dynamic model of air rudder rotation around the rudder shaft, considering a dry friction model with rotational clearance and Stribeck effect, and establishing the forced vibration equation of air rudder rotation with clearance and dry friction. The average method is applied to analyze the amplitude frequency characteristics of the rotational direction. The influence of different friction torque coefficients and external excitation frequencies on the amplitude frequency response of axial vibration is studied. The results show that when the external excitation frequency changes, the amplitude frequency curve of the vibration around the axis exhibits hysteresis nonlinear characteristics of different softness and hardness. Multiple solution frequency bands appear in the frequency domain, and the frequency domain multiple solution frequency bands increase with the increase of the friction torque coefficient.

In order to study the mixing and explosion characteristics of liquid oxygen and kerosene, a partial confined space test system is established to simulate the application scenarios of the launch site and the tests are carried out. It is demonstrated that when liquid oxygen and kerosene are discharged and mixed at the same time, the concentration of kerosene and oxygen increases at first and then decreases. When kerosene temperature is ${65}^{\circ}\mathrm{C}$ and ignition excitation is ${5.9}\mathrm{\;J}$, even if liquid oxygen leaks, the ignition and explosion condition are still not reached at the measuring points arranged above the liquid level. In the test when the kerosene temperature is raised to ${80}^{\circ}\mathrm{C}$, explosion occurs when liquid oxygen is released only for about 20 seconds. At ignition time, the concentration of kerosene, oxygen, and nitrogen are ${1.31}\%,{40.05}\%$ and ${58.64}\%$ respectively, and the ratio of kerosene concentration to oxygen concentration is 0.033 .

The optics window is usually faced with severe aerodynamic heating, and there is a prominent image saturation problem because of high temperature. Therefore, researchers often use film cooling to isolate the direct heat convection from the outflow. A tangential high-density cooling film generation structure is designed which is used for high pressure and heat flux. Through reasonable ground test, numerical simulation and engineering calculation, the main factors affecting the cooling efficiency are studied. The preliminary results show that tangential high density gas film can reliably reduce the surface heat at high pressure and high heat flux. The research effectively adapts to the increasingly harsh optical observation environment.