• 한국기계가공학회지
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• 제17권1호
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• pp.8-15
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• 2018

Recently, the manufacturing market for low-cost airlines has led to an increase in aircraft demand. Most processes in the production of these aircrafts are manual such as drilling, sealing, and swaging. A drilling and riveting machine is a numerical-control based equipment that automatically performs drilling, sealing, and swaging operations. The accuracy of the drilled holes and the exit burr length has a significant impact on the quality of the aircraft wing during assembly. This study was conducted to identify the conditions necessary to maintain a uniform quality by controlling the rotation speed of the spindle, which directly affects the hole diameter and the quality of the exit burr.

• 한국군사과학기술학회지
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• 제24권3호
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• pp.302-308
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• 2021

Developers generally use test standards suggested by military standards such as MIL-STD-810G when performing vibration tests in the materiel development. However, according to MIL-STD-810G, it is recommended to test by tailoring the test standard suitable for the developed materiel, and it is specified to apply the suggested test standard only when there is difficulty in tailoring. In addition, the test standards presented by MIL-STD-810G are standards created under operating conditions different from the actual operating environment of each developed materiel, so the test according to this standard may be excessive or understated. Therefore, the developer must create an appropriate vibration test standard for the developed materiel as similar to the operating conditions as possible. In this paper, the procedure for creating the functional test standard and durability test standard suitable for the operating environment of the equipment to be mounted on the propeller aircraft under development is described, and the created standard is introduced.

• Advances in aircraft and spacecraft science
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• 제8권4호
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• pp.289-302
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• 2021

Ensuring flight safety for passengers as well as crew is the most important aspect of modern aviation, and in order to achieve this, it is necessary to be able to forecast the durability of individual components. The present contribution illustrates the results of a computational analysis to determine the possibility of analysing the prediction of bearing durability in on-board rotating equipment from the point of view of thermal fatigue.In this study, a method developed at the Air Force Institute of Technology was used for analysis, which allowed to determine the bearing durability from the flight altitude profile. Two aircraft have been chosen for analysis - a military M-28 and a civilian Embraer. As a result of the analysis were obtained: the bearing durability in on-board rotating devices, average operation time between failures, as well as failure rate. In conclusion, the practical applicability of this approach is demonstrated by the fact that even with a limited number of flight parameters, it is possible to estimate bearing durability and increase flight safety by regular inspections.

• 한국정밀공학회지
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• 제17권10호
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• pp.49-55
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• 2000

This study describes the fatigue characteristics for Al2024 alloy, which is aircraft structure material. For this work, the plane-strain fracture toughness test, the plane-stress fracture toughness test and the crack growth rates test were conducted under the standard testing method. Test equipment is a computer-controlled closed-loop fatigue testing machine. The data of each test result is very important to aircraft structure reliability estimation, life prediction, design analysis, endurance analysis and damage tolerance analysis. In addition, the fatigue crack growth threshold($\DeltaKth$) value decreased as the stress ratio increased. Also, $\DeltaKth$ decreased as the thickness increased in LT, TL directions.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.101-106
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• 2002

Requirements to fabrication processes for arc welding of highly loaded thick-walled joint and problems of research and development in term s of the tendency for the modern aircraft structure development are outlined. A justified, choice of the development line of the new promising welding processes for solution of these problems is presented. A complex of new welding processes and technologies for making highly reliable joints with different thickness (up to 120 mm and more) and length of weld (up to 0.1 m; 0.1-0.5 m and more than 0.5 m) has bee developed. It is shown that the possibility to control the heat flow distribution over the groove surface of the welded joints provides for improved reliability. The new welding processes are equipment are effectively used in serial production of the Mykoyan md Sukhoi supersonic aircrafts as well as in AN-124 Ruslan and AN-225 Mriya wide body aircrafts.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1384-1387
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• 2003

Pressurization test is usually required in aircraft full-scale static test. There are several test conditions including pressurization of cockpit, fuselage fuel tank, air inlet duct for T-50 full-scale static test. In this paper, the test conditions, equipment, piping analysis for the pressurization test are introduced. Tank simulation test is performed to verify the validity of piping analysis and to find good tuning parameters for the pressurization channel in the servo controller. Several test setup for pressurization of T-50 test is introduced. Test article volume is filled by form, $60%{\sim}80%$ volume is reduced for the T-50 full-scale static test. Pressurization system is connected to servo controller which also controls hydraulic actuator. Load and pressure control is synchronized by using the same servo controller during T-50 test. Typical control result for pressurization test condition is shown. Pressurization tests of T-50 full-scale static test was completed successfully.

• 항공우주시스템공학회지
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• 제5권1호
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• pp.13-16
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• 2011

All components such as structure, engine, electrical equipment, wire etc. should have certified qualities and functions for safe flight. The wire like a blood vessel of man is connected with most components and supply a electrical signal or power to them and only certified wire through a lot of tests such as rating, flame resistance, self-extinguishing, protection of EMI etc. must be used in aircraft. In other words, the wire should observe many certification requirements because it is one of the most important components.

• 한국산학기술학회논문지
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• 제9권3호
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• pp.632-637
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• 2008

군용 항공기 탑재 무장제어장치는 무장관리시스템의 핵심장비로 조종사의 무장선택, 항공기 상태 및 외부 장착물 장착 상태 등에 따라 선택투하, 비상 투하 및 로켓발사 신호를 생성하여 외부 장착물을 제어한다. 본 논문은 순차 제어회로 설계기법을 이용하여 개발된 무장제어장치의 설계과정 및 성능검증에 대해 기술한다.

• 항공우주시스템공학회지
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• 제14권6호
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• pp.10-17
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• 2020

The Korean medical evacuation helicopter was developed based on the Korean Utility Helicopter (hereafter referred to as 'Surion'). It uses an auxiliary power unit and engine for heating during winter operation. The helicopter maintains the internal temperature of the aircraft using its bleed air to satisfy its operational capability. However, due to the air inflow through the gap between the aircraft skin and door, additional heating for operating the portable medical equipment and preventing hypothermia in evacuated patients is required. Accordingly, an electric auxiliary heater was developed for additional heating during winter operation, and environmental, durability, and performance tests were conducted per MIL-STD-810G and MIL-STD-461F. The auxiliary heater was verified per the tailored airworthiness certification criteria.

• 항공우주정책ㆍ법학회지
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• 제33권2호
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• pp.367-418
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• 2018

항공에 있어서 안전이 가장 중요한 것처럼 무인항공기 운영에 있어서도 안전이 가장 중요하고 무인항공기 운영자의 법적책임에 있어서도 안전운영책임이 가장 중요하다고 할 수 있다. 본 논문에서는 무인항공기 운영자의 안전운영 책임을 중심으로 무인항공기 운영자가 지게 되는 법적책임 문제를 사고 발생 시 피해를 보상해주는 보험 문제와 함께 심도있게 고찰하였다. 우선 무인항공기 운영자의 법적책임 문제는 가장 기본적인 무인항공기 운영자의 정의, 범위, 자격요건을 살펴보고 규제동향으로 국제민간항공협약, ICAO 부속서와 RPAS Manual, 로마협약 등 주요 국제협약, 항공안전법 등 국내 관련 법률상의 운영자의 책임규정을 고찰하였다. ICAO에서는 무인항공기도 궁극적으로는 유인항공기와 동등한 수준의 기술상 및 운항상의 안전성을 확보할 것을 요구하고 있으며 무인항공기 운영의 대원칙으로 사람, 재산 및 다른 항공기에 대한 위험을 최소화 하는 방법으로 운영 되어야 한다고 규정하고 있다. 이와 관련 무인항공기 사고의 경우는 대부분이 지상에 추락하여 제3자의 인명이나 재산에 피해를 입히는 사고가 대부분인 점을 감안 관련 국제협약인 로마 협약상의 운영자의 책임과 국내 상법 항공운송편의 제3자 책임 관련 규정을 중점적으로 살펴보았으며 사고 발생에 따른 배상책임 문제도 살펴보았다. 로마협약과 관련하여서는 1952년 로마협약이 운영자의 책임을 상세히 규정하고 있다. 배상책임과 관련하여서는 아직 발효는 되지 않았지만 EU 일부국가에서는 2009년 로마협약상의 책임한도액을 따르고 있는 점이 특징이다. 아직 우리나라는 어떠한 로마협약에도 가입하지 않고 있으나 상법 항공운송편은 배상책임에 있어 1978년 로마협약을 모델로 하고 있다. 이들 이외에 무인항공기 운영에 따르는 관련 법적책임으로 가장 많이 문제가 되고 있는 보안관련 책임과 사생활 침해에 대한 책임도 살펴보았다. 보험과 관련하여서는 전 세계적으로 항공보험의 가입 의무화 경향과 이에 따른 주요 각국의 규제현황을 살펴보고 무인항공기에의 적용 가능성을 살펴보았다. 또한 현행 국내 항공사업법상의 보험가입 의무화 조항과 초경량 비행장치 보험 규정과 문제점을 살펴보았다. 요컨대 무인항공기 운영자는 무인항공기를 인명이나 재산 또는 다른 항공기에 위험을 주지 않도록 안전하게 운영할 법적책임이 있으며 사고 발생 시는 적절한 보상책임이 있다고 할 것이며 이를 위한 보험제도 등 법제도적 장치가 마련되어야 한다.