• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.6
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• pp.103-120
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• 2010

A development history of the thrusters used for space-vehicle orbit maneuver/attitude control is reviewed with their performance characteristics. Especially, a scrutiny is made for the current and practical application of TVC/Gimbal/Thrusters to the roll/pitch/yaw-axis control of each stage of launch vehicles. It is well perceived that a precise 3-axis attitude control system (ACS) must be equipped on the final stage of space launch vehicles (SLV) for an attainment of orbit-insertion accuracy. Under the superior reliability as well as moderate performance features, the monopropellant hydrazine thrusters occupy most of the SLV's 3-axis ACS currently operated. Domestic development status of the medium-thrust-level thruster is shortly introduced, finally.

• Journal of Astronomy and Space Sciences
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• v.1 no.1
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• pp.5-21
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• 1984

The airflow along the surface of a launch vehicle together with base flow of clustered nozzles cause problems which may affect the stability or efficiency of the entire vehicle. The problem may occur when the vehicle is on the launching pad or even during flight. As for such problems, local steady-state loads, overall steady-state loads, buffet, ground wind loads, base heating and rocket-nozzle hinge moments are examined here specifically.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.4
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• pp.251-257
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• 2022

We formulated the convex optimization based minimum energy soft landing problem for reusable launch vehicles, and obtained the minimum time trajectory via the bisection search. In order to implement the the optimal guidance command and complete the flight control architectures on the soft landing stage, we designed the classical attitude control loops, and formulated and solved the optimal actuator allocation problem. The obtained soft landing guidance performance was analyzed via nonlinear 6-DOF simulation.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.180-185
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• 2021

In accordance with the revision of the US-Korea missile guidelines, restrictions on the use of solid propellants for space launch vehicles have been completely lifted. The solid propellant can be used as a solid propellant rocket like the KSR-1 (Korea Sounding Rocket-1), and can also be used as a thrust augmentation booster for liquid fuel launch vehicles. It is known that solid propellants have a lower risk of explosion than liquid propellants. but if an accident such as an explosion at the Alcantara Launch Center in Brazil occurs, it can lead to a large-scale personal accident. In order to prevent such large-scale accidents, it is necessary to review and reflect the minimum safety distance during use, storage and combustion test of solid propellants from the planning phase of the project. In this paper, the minimum safety distance for safe use of the solid propellant is presented by dividing it into storage facilities and combustion tests.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.6
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• pp.48-55
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• 2012

An ambient hot-firing test was carried out for the hydrazine thruster which may be employed in the space launch vehicles. The thruster is designed to produce 67 N (15 $lb_f$) of nominal steady-state thrust at an inlet pressure of 2.41 MPa (350 psia). A scrutiny into the performance characteristics of thruster is made in terms of thrust, propellant supply pressure, mass flow rate, chamber pressure, and temperature at the steady-state firing mode. As a result, it is ensured that the practical performance efficiencies are above 89.1% compared to its ideal requirements.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.123-130
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• 2008

Flight safety analysis, which includes risk estimation for the various abnormal flight modes in addition to normal flight, has to be performed necessarily to guarantee launch safety for the operation of space launch vehicles. For this purpose, a dedicated system has been developed such that all the necessary repetitive computations, result reports, and graphical presentations can be performed inside a single system for user convenience. In addition, the developed system is capable of representing computed results on a three dimensional Earth for the realistic presentation. The developed Flight Safety Analysis System will be employed for the launch operation of Korea Satellite Launch Vehicle-I.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.2
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• pp.139-155
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• 2016

Present paper introduces the recent advances in space launch vehicle technologies. A brief survey is given for the space development programs in civil sector with their business model and key technologies. Advances in key technologies were reviewed in detail with more emphasis on the electric pump cycle engine for low cost high performance small launch vehicle, Electron, under development by Rocketlab Ltd., since their contributions would give good lessons for rocket scientists.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.3
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• pp.203-214
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• 2022

As the global demand for small satellites weighing less than 500 kg increases, the development and operation of dedicated small launch vehicles increase significantly. The responsiveness of a launch vehicle that puts a small satellite into a target orbit at the desired time is attracting attention. As a result, interest in the air launch is increasing in the rapid establishment of a constellation. As the demand for small satellites in south Korea increases, this study performed analyses on the applicability of an air launch vehicle using a large civil aircraft considering the geographical environment. In terms of responsiveness, mission response times were compared and analyzed for air launch vehicles and ground small and large vehicles. In addition, an air vehicle and a small ground vehicle were quantitatively compared and analyzed for the orbital insertion performance. As a result of the analysis, the air launch vehicle has limited responsiveness in Korea regarding rapid satellite constellation establishment. However, it can be an effective alternative for low inclination angle orbit insertion with the benefit of a fast turnaround time. Furthermore, the performance of the orbital injection is close to that of the ground small launch vehicle, and the high efficiency in terms of the required propellant mass is possible, so air launch can be an effective launch means for putting small satellites into orbit in Korea.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.7
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• pp.544-551
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• 2014

A program of launch vehicle performance analysis is composed for the education of the conceptual design of launch vehicles and the requirement analysis for the propulsion system design. The program is applied for the mission analysis of space launch vehicles based on KSLV-II with liquid rocket boosters. The 75-ton class liquid rocket engine is assumed for the boosters by referring the mass ratio of KSLV-II second stage. The launch performance analysis is carried out for KSLV-II with 2, 3 and 4 boosters by targeting the circular orbit of 700 km altitude. The trajectory is assumed as two-dimension considering the variation of the flight environment. Payload of advanced KSLV-II could be increased to maximum 3 tons, though it is limited by the thrust performance of the upper stage.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.4
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• pp.67-77
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• 2021

Space development has been led by the state due to huge investment, risks of development failure, and restrictions on international cooperation on technology development and transfer. For this reason, it has been developed mainly by some advanced countries and industrial network formed among them. However, Korean space industry is being promoted by the successful launch of 'KSLV-I' and 'CAS 500-I' and the space launch vehicle "KSLV-II" under development. Recently, Korea and U.S. agreed to end bilateral missile guidelines. Therefore it is expected that development of Korean space industry will be accelerated due to the disappearance of the constraining factors for the development of space launch vehicles. Accordingly, this study examined the development and formation of the Korean space industry through the framework of network analysis. Based on this, the effect of structural position in the industrial network as a resource on the performance of Korean space companies was examined. Panel analysis was applied. Through this study, ideas for fostering the domestic space industry and implications for national policy related with building an industrial ecosystem are derived. It contributes to the development of space industry in Korea.