• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.11-19
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• 2002

Inflating characteristics of the parachute canopies have been experimentally investigated with the objective of measuring the parachute opening parameters such as canopy filling time and the peak opening force using scaled parachute models. A device has been made and tested to eject a model parachute into a wind tunnel flow and to measure the drag force acting on it. The force-time histories and the peak opening force are obtained, and these comparative aerodynamic characteristics were analyzed and discussed, including the effect of forebody wake. The opening of the ringslot parachute model appeared to be faster than that of the available similar data by about 10~40%, and fair to good agreement was obtained for the reefed ribbon parachute.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.6
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• pp.465-472
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• 2013

In this paper, we suggest how to determine the parachute deploy position for accurate landing of a UAV at a desired position. The 9-DOF dynamic modeling of UAV-parachute system is required to construct the proposed algorithm based on neural network nonlinear function approximation technique. The input and output data sets to train the neural network are obtained from simulation results using UAV-parachute 9-DOF model. The input data consist of the deploy position, UAV's velocity, and wind velocity. The output data consist of the cross range and down range of landing positions. So we predict the relative landing position from the current UAV position. The deploy position is then determined through distance compensations for the relative landing positions from the desired landing position. The deploy position is consistently calculated and updated.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.8
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• pp.726-736
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• 2012

This paper deals with Spin/Stall Recovery Parachute System from design to ground taxiing stage which would be deployed on the high speed taxi of turbo-prop airplane. In detail design phase, design parameters- riser length, parachute type, size, porosity, parachute canopy filling time, and deployment method- were considered based on the analytical disciplines such as aerodynamics, structures, and stability & control. Before the installation of Spin/Stall Recovery System of turbo-prop airplane, all control functions of this system were validated by the SBTB(System Breakout Test Box) in the laboratory. SBTB was used to confirm if it can detect faults, and simulate the firing of pyrotechnic devices that control the deployment and jettison of it. Once confirmed normal operation, deployment of parachute on the high speed taxiing were performed.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.137-146
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• 2001

According to the advanced development of Light Weight Torpedo, the overall items related with the parachute type and gore layout and air stabilizer of the parachute for fixed and rotary wing aircraft are described in this paper. Also, the drag-area which should satisfy the firing envelope, parachute inflation characteristics, stability of parachute and torpedo in airdropping, water entry impact on torpedo and parachute constituted the principle design factors. The important trial and errors occurred in the step of performance of the parachute for fixed and rotary wing aircraft are investigated and analyzed.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.3
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• pp.345-351
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• 2017

A wind tunnel test for the scaled parachute models was performed to verify aerodynamic characteristics for practical usage of Korean low cost low altitude aerial delivery system. The cruciform shaped cargo parachute models for heavy and light weight were ejected into wind tunnel test section; and the drag forces acting on the models in steady condition were measured in accordance with velocity. Also, the maximum opening forces during inflation were obtained and captured by a high speed camera to analyze the inflation characteristics and evaluate the design of the low cost aerial delivery system. The results showed a reliable stability and met the design requirement of delivery operation system for R.O.K Air Force.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.47-48
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• 2001

오징어채낚기 어업은 우리나라 연근해 어업 생산량의 약 7％를 차지하는 주요 어업 중 하나이다. 오징어 채낚기 어선은 조업 중 낙하산 모양의 물돛을 사용하여 조획률을 높이고 낚시끼리 서로 얽히지 않게 하여 효과적으로 조업을 수행할 수 있도록 한다 (金田, 1992). 본 연구에서는 물돛의 형상과 규격에 따른 유체역학적 특성을 모형 물돛의 항력과 항력계수, 전개율 등 정량적인 역학 특성을 산출하여 구명하였다. (중략)

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.4
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• pp.375-383
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• 2008

Design of a weapon-carrier type of missile requires to provide a highly reliable mechanism of airframe separation and air stabilizer deployment which enables the safe release of payload at high-speed flight conditions. This mechanism is characterized by a relative dynamic motion of multiple separated bodies, proceeding as swiftly as hundreds of milli-seconds, so that the use of modeling & simulation(M&S)techniques could play a crucial role in the design. This paper presents an M&S technique which has been developed for a design of anti-submarine missile employing a clamshell type of airframe separation, and shows some major results of simulation compared to available flight test results. Emphasis of the current study was laid on a proper balance between the quick calculation, which is essential for practical design application, and the credibility of the results.