• International Journal of Aeronautical and Space Sciences
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• 제2권1호
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• pp.28-43
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• 2001

Developed in these two series of paper is a complex dynamic model representing the motion of aircraft on the ground and a computer program for numerical simulation. The first part of paper presents the theoretical derivation of equations of motion of the landing gear system based on the physical principle. Developed model is 'structured' in the sense that the undercarriage system is regarded as an assembly of strut, tire, and wheel, where each component is modeled by a separate module. These modules are linked with two external modules-the aircraft and the runway characteristics-to carry out dynamic analysis and numerical simulation of the aircraft motion on the ground. Three sets of coordinate system associated with strut, wheel/tire and runway are defined, and external loads to each component and response characteristics are examined. Lagrangian formulation is used to derive the undercarriage equations of motion relative to the moving aircraft, and the resultant forces and moments from the undercarriage are transformed to aircraft body axes.

• 한국항공운항학회지
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• 제21권1호
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• pp.1-7
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• 2013

To have the competitiveness in the future worldwide small aircraft market, we should be able to develop the aircraft which is highly safe, easy to fly, and having excellent flight characteristics. FBW(Fly-By Wire) system is essential for the enhancement of flight safety and control easiness. FBW system that has been applied only to the modern fighter and transport aircraft is recently applied to smaller aircraft such as regional aircraft, business aircraft and even small aircraft. The purpose of this research includes the development of flight control computer, the definition of FBW system component, the design concept of each component for redundant management, OFP(Operational Flight Program) development, FBW system integration and HILS(Hardware In-the Loop Simulation) verification environment to test this FBW system.

• 한국항공우주학회지
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• 제49권9호
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• pp.801-811
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• 2021

낙뢰는 짧은 시간 동안 다량의 에너지를 항공기에 전달하여 치명적인 결과를 초래할 수 있다. 특히 낙뢰는 고온의 열과 전류를 동반하여 항공기 표면 손상과 내부 전자장비에 영향을 미쳐 비행의 안전에 심각한 영향을 미칠 수 있다. 이를 분석하기 위한 낙뢰 시험에는 미항공우주원고서 SAE ARP 5412B에 규정된 최대전류 200kA인 Component A 파형이 사용된다. 하지만 실제 낙뢰 크기는 대부분 35kA 내외로 발생하며 전기체 대상으로 하는 낙뢰 간접 시험에서 내부 전자장비 손상 예방을 위해 파형을 축소하여 시험을 진행한다. 본 연구에서는 기존 Component A 축소 파형을 도식화하는 방법을 알아보고 그 한계를 분석하였다. 나아가 항공기 낙뢰 Component A 파형의 보정계수를 조절하는 방식의 신규 축소 파형 도식 방법을 제안한다. 마지막으로 전자기 해석 소프트웨어 EMA3D를 활용하여 EC-155B 헬리콥터 내부 케이블 하네스의 파형 감소비에 따른 내부 유도 전류 크기 감소비를 비교하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2007년도 추계학술대회 및 정기총회
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• pp.43-57
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• 2007

This paper considers the technological competitiveness of aircraft infra industries that are bases of the aircraft industry development in Korea. We performed focus group interviews to aircraft industry specialists and classified the aircraft infra industries by eight fields: metallurgical assembly, general machinery, precision instruments, materials & parts, communication appliances, computer, semi-conductor/ electronic component, electronics. Through the United States patents analysis for the G7 countries and Korea during 1995-2006, we identified the technological specificities and competences of each country. RTA(Revealed Technology Advantage) index and CII(Current Impact Index) are used to examine the technological specificity and technological competence respectively. Finally, we introduced TCI(Technological Competitiveness Index) which could reflect quantitative level as well as qualitative level of patents for each aircraft infra industry. The results show that Korea has occupied the technological competitiveness in the semi-conductor and electronic component industry out of eight aircraft infra industries, and achieved a competitive edge in communication appliance industry in the mid 2000s.

• 항공우주시스템공학회지
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• 제13권5호
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• pp.79-86
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• 2019

회전익 항공기의 충돌방지등은 항공기 운용 중 충돌을 방지하기 위한 목적으로 사용되며, 비행 안전성을 확보하기 위한 핵심 구성품이다. 한국형 기동헬기(KUH)의 충돌방지등은 상부등과 하부등으로 구성되며, 충돌방지등 전원공급기와 항공기에 함께 장착되어 운용된다. 그리고 충돌방지등은 밝기 조절 및 선택적 점등이 가능한 이중 구조로 설계되었다. 항공기 납품 후 운용 과정에서 충돌방지등의 이상점 등이 발생하였고, 이러한 현상을 해소하기 위하여 항공기 체계/구성품 단위의 종합 검토를 수행하였다. 본 논문에서는 충돌방지등의 이상점등이 발생한 원인을 분석하였고, 설계 개선방안을 제시하였다. 그리고 설계 개선방안에 대한 타당성을 구성품 및 항공기 체계 지상 및 비행시험으로 입증하였다.

• 한국항공운항학회지
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• 제24권2호
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• pp.19-24
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• 2016

Positional stability analysis based on aerodynamic forces and induced moments of formation flight using two small aircraft models is presented. The aerodynamic force and moments of the trailing aircraft are analyzed in the aspect of flight stability. The induced moments with the change of local flow direction by wing-tip vortex from the leading aircraft can affect the flight positional stability of aircraft in closed formation flight. Aerodynamic forces and moments of trailing aircraft model are measured by 6-component internal balance at the 49 locations with vertical and lateral space between two aircraft models. Results are shown that the positional stability of trailing aircraft in formation flight can be analyzed by positional stability derivatives with vertical and lateral space. It is concluded that flying positions can be important factors for aircraft position stability due to induced aerodynamic force and moments with vertical and lateral spacing by the variation of flow pattern from the leading aircraft in formation flight.

• 항공우주시스템공학회지
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• 제6권1호
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• pp.13-18
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• 2012

This paper presents a structural health monitoring method of aircraft reciprocating engine using Principal Component Analysis (PCA) which analyzes vibration expressed by Averaged Normalized Power Spectral Density (ANPSD). Because ANPSD of the rotating shaft is sensitive to the rotating speed, this paper proposes to use a post-processing method of ANPSD is used to reduce the sensitivity. The PCA extracts compressed information from the post-processed ANPSDs and the information means the difference between current and normal cases of the engine. The experimental results demonstrate the feasibility and effectiveness of the proposed method to detect abnormal cases of the engine.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.680-683
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• 2005

The wing component model for flutter analysis consisting of stiffness, mass, and aerodynamic model has been constructed based on the full airframe finite element model for 4-seat canard-type small aircraft. A study on wing flutter characteristics has been investigated based on the wing component model constructed using PK method in MSC/NASTRAN for flutter analysis. In addition, wing flutter mechanism for the aircraft under consideration has been analyzed based on the results of normal mode and flutter analysis.

• 한국군사과학기술학회지
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• 제3권1호
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• pp.92-105
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• 2000

Core technologies of powerplants, which are necessary for the development of Korean type combat aircraft, are analyzed. And then, the acquisition methodologies for the technologies are proposed. With respect to the aircraft engine design and manufacturing technologies, simple basic technologies such as component manufacturing and assembling technology come to close to those of advanced countries, but the core technologies were not acquired or in the understanding level only. Therefore, the research on the component manufacturing technology should be specialized for buildup of international competition first, and the research on core technologies such as high pressure compressor design, blisk, FADEC and hollow fan blade design should be concentrated step by step by taking an active participation in the development project of international cooperative aircraft powerplants.

• 경영과학
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• 제25권2호
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• pp.111-127
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• 2008

This paper analyzes the technological competitiveness of aircraft-based industries that are the basis for the development of aircraft industry in Korea. By performing expert interviews with industry specialists in the field of aircraft technology, the paper categorizes eight fields that are fundamental to the development of the aircraft industry. By analyzing patents of G7 countries and Korea made in the US from 1995 to 2006 we were able to identify the technological specificities and competencies of each country. RTA (Revealed Technology Advantage) index and CII (Current Impact Index) are used to examine the technological specificity and technological competence respectively. Finally, by introducing the TCI (Technological Competitiveness Index) the paper is able to consider both the quantitative level and the qualitative level of patents for each field in the aircraft industry. By analyzing the TCI, the paper concludes that Korea has high technological prowess centered around IT industries such as semi-conductors/ electronics component, communication appliances and consumer electronics. Also Korea is relatively competitive in the precision instruments industry.