• Advances in aircraft and spacecraft science
• /
• v.9 no.3
• /
• pp.263-278
• /
• 2022

The time-varying structural reliability of an aeroelastic launch vehicle subjected to stochastic parameters is investigated. The launch vehicle structure is under the combined action of several stochastic loads that include aerodynamics, thrust as well as internal combustion pressure. The launch vehicle's main body structural flexibility is modeled via the normal mode shapes of a free-free Euler beam, where the aerodynamic loadings on the vehicle are due to force on each incremental section of the vehicle. The rigid and elastic coupled nonlinear equations of motion are derived following the Lagrangian approach that results in a complete aeroelastic simulation for the prediction of the instantaneous launch vehicle rigid-body motion as well as the body elastic deformations. Reliability analysis has been performed based on two distinct limit state functions, defined as the maximum launch vehicle tip elastic deformation and also the maximum allowable stress occurring along the launch vehicle total length. In this fashion, the time-dependent reliability problem can be converted into an equivalent time-invariant reliability problem. Subsequently, the first-order reliability method, as well as the Monte Carlo simulation schemes, are employed to determine and verify the aeroelastic launch vehicle dynamic failure probability for a given flight time.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.36 no.3
• /
• pp.291-297
• /
• 2008

The launch of the COMS by using Ariane-5 launch vehicle is introduced. First, the COMS is introduced briefly, and then, the Ariane-5 launch vehicle is introduced including detail description of the improvement of Vulcain-1 engine of Ariane-5G to Vulcain-2 engine of Ariane-5ECA for 20% increase of thrust. Then, the launch process of the COMS is introduced. The COMS will be launched from the Guiana Space Center in Kourou, French Guiana. After the final check at PPF the COMS is transferred to HPF in the same building for fueling, and it is integrated to the launch vehicle adaptor at HPF, too. Then, this assembly is transferred to Final Assembly Building. After the satellites to be launched together are integrated to the launch vehicle on the launch table in the Final Assembly Building, the launch table loaded with the launch vehicle is moved to the launch pad for launch. The events during the launch vehicle flight is also introduced.

• Journal of the Korean Society of Systems Engineering
• /
• v.12 no.2
• /
• pp.19-27
• /
• 2016

Many countries concentrated on the space developments to enhance the national security and the people's quality of life. A space launch vehicle for accessing the space is a typical large complex system that is composed of the high-technology like high-performance, high-reliability, superhigh-pressure, etc. The project developing large complex system like space launcher is mostly conducted in the uncertain environment. To achieve a goal of the project, its success probability should be enhanced consistently by reducing its uncertainty during the life cycle: it's possible to reduce the project's uncertainty by performing the risk management (RM) that is a method for identifying and tracing potential risk factors in order to eliminate the risks of the project. In this paper, we introduce the risk management (RM) process applied for a Space Launch Vehicle R&D Project.

• 한국전산유체공학회:학술대회논문집
• /
• 2004.03a
• /
• pp.17-22
• /
• 2004

A space launch vehicle departs the ground in a low speed, soon reaches a transonic and a supersonic speed, and then flies in a hypersonic speed into the space. Therefore, the design of a launch vehicle should include the prediction of aerodynamic characteristics for all speed regimes, ranging from subsonic to hypersonic speed. Generally, Empirical and analytical methods and wind tunnel tests are used for the prediction of aerodynamic characteristics. This research presents considerable factors for aerodynamic analysis of a launch vehicle using CFD. This investigation was conducted to determine effects of wake over the base section on the aerodynamic characteristics of a launch vehicle and also performed to determine effects of the sting which exist to support wind tunnel test model.

• Journal of Environmental Science International
• /
• v.31 no.7
• /
• pp.543-553
• /
• 2022

The latest aerospace technology is important for the stable flight of a launch vehicle, but weather conditions on the day of launch are also one of the essential factors for successful launch campaign. If a launch vehicle is directly struck while preparing to take off from the launch pad on the day of launch or the electronic device are damaged by induced current during flight of the launch vehicle, this means launch failure and can lead to enormous national loss. Therefore, for a successful launch campaign, it is necessary to analyze the lightning detection characteristics of the Naro Space Center. In this study, the seasonal factors of the lightning that occurred over the Naro Space Center from 2003 to 2017, the influence of the polarity, and the correlation with the lightning intensity was confirmed. As a result, there was a high probability of intensive occurrence of multiple lightning strikes in summer, and a high proportion of positive (+) lightning strikes in winter. Lastly, in the distribution of the number of lightning strikes, an average of 2.0 to 2.5 negative (-) lightning strikes occurs in the coastal regions of the South and West Seas when one flash happens.

• Journal of the Korean Society of Systems Engineering
• /
• v.2 no.1
• /
• pp.37-41
• /
• 2006

The KSLV-I satellite launch vehicle will be launched in a space center currently under construction. The Space Center which is an advance post base of space development of Korea is located on Oenaro island in Kohung, South Cholla Province. A Ground Complex of the Space Center consists of an AC(Assembly Complex), a LC(Launch Complex), and a MCC(Mission Control Center). Assembly and test facilities are located in the AC in which stage assembly, integrated assembly, check-up, certification test, and pre-launch test are made effectively. A launch pad, fuel supply facilities, a launch control center and associated supporting facilities are located in the LC, and the MCC has control over the space center. These ground complex facilities have diverse forms of an interface with mechanical device, electric device, and etc. These should also provide optimum condition and performance during launch operation processes of the launch vehicle. This paper introduces the result of R&D for the AC of the ground complex performed during system design period.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.6
• /
• pp.567-575
• /
• 2011

The development of space launch vehicle is an important step to advance to developed countries in the space area. It is also so risky due to necessity of huge costs and longer development period. The accuracy of cost estimation is important to develop a space launch vehicle successfully and efficiently. It is also necessary to estimate production and operation cost in order to develop commercial space launch vehicle possessing competitiveness. In this paper, Korean factors to be able to reflect the current state of workforce, average working hours and technology readiness level in Korea were analyzed to estimate production and operation cost of space launch vehicles that are developed in Korea. Korean factors have been applied to production and operation cost estimation of KSLV-II based on TRANSCOST. We evaluated the competitiveness level of KSLV-II as the commercial launch vehicle in the commercial launch services market by comparing with cost per flight of foreign launch vehicles.

• Journal of Applied Reliability
• /
• v.4 no.2
• /
• pp.105-119
• /
• 2004

Reliability program is essential to the development of space systems like launch vehicles and satellites, as they are non-repairable after launch and the failure of a launch vehicle resulted in catastrophic consequences for the mission. Foreign advanced space organizations have developed and implemented their own reliability management programs for launch vehicles from the conceptual design stage to the detail processes for the individual components, procedures and test reports. A study on the launch failures and the reliability analysis methods for one-shot devices contained in this paper will contribute to the reliability improvement for Korean launch vehicle and components.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.12
• /
• pp.997-1010
• /
• 2021

This study collected and analyzed flight data of SpaceX's Falcon 9 launch vehicle. All missions were classified by orbital types, such as Polar, SSO, ISS, LEO and GTO missions. In characteristic maneuvers of main engine cutoff, boostback, reentry and landing burn at each stage of 1st stage launch vehicle, changes of the physical parameters like speed, altitude, dynamic pressure and acceleration were investigated. The guidelines derived from detailed maneuver analysis were suggested, which can be used as design and evaluation references for developing reusable launch vehicle.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03b
• /
• pp.393-396
• /
• 2008

Propellant consumption control for space launch vehicle can be achieved by propellant utilization system (PUS) and tank depletion system (TDS). In the course of developing new space launch vehicles, the main target of design is on reducing of space launch vehicle weight, which results in increasing both specific impulse and payload weight. The weights of space launch vehicles are generally allocated to structure, propulsion system, and propellants loaded. The quantity of propellants filled in propellant tanks may be estimated with the propellants actually consumed by propulsion system to complete its mission and the propellants left on-board at the time of engine shut-off. To minimize the remaining quantity of propellants on-board the supplying propellants' O/F ratio should be controlled from the certain time before engine shutdown. To control an O/F ratio, a control system, which accurately measures and compares the remainder of propellants in tanks and pipes, should be needed. This paper solely dedicates its contents to explore the merits and demerits of various level sensor, which is one of the important elements for PUS and TDS, and the transmission and control of signals within space launch vehicle.