• 한국추진공학회지
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• 제3권1호
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• pp.104-117
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• 1999

복합재료는 비강성과 비강도의 우수성 때문에 첨단 산업분야에서 사용되고 있으며, 특히 낮은 비중으로 인한 중량감소 효과와 접착과 주조 둥에 의한 부품수의 감소효과 때문에 항공기와 수송기계분야에 널리 이용되고 있다. 복합재료의 이러한 장점들을 이용하여 항공기용 동력전달축과 자동차용 추진축에서 연구와 활용이 이뤄지고 있다. 본 연구에서는 우수한 진동 안정성을 갖는 복합재료 추진축을 설계하고 해석하였으며 이를 증명하기 위해 충격망치를 이용한 FFT해석기와 회전장비를 이용하는 두 가지 실험을 수행하였다.

• 드라이브 ㆍ 컨트롤
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• 제9권2호
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• pp.39-45
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• 2012

The NAS 1638 cleanliness classification system was originally developed in 1966 by the US Aircraft Industries of America to both simplify reporting of particle count data and to control the introduction of dirt during the assembly of aircraft fluid systems. The numbers of particles at stated sizes are represented by broad bands where the interval was generally a doubling of contamination. A number of systems have been introduced since this to suit differing requirements. NAS 1638 and AS4059 are used in other industrial sectors such as the Off-shore & Sub-Sea and the Primary Metal Industries. The changes to ISO contamination measurement standards controlled by ISO/TC131/SC6 in 1999 meant that a revision of most of these classification systems was necessary. The body responsible for NAS 1638 decided to withdraw it for new installations and replace it with an update of an existing standard, SAE AS 4059. This paper details the philosophy behind the contamination coding systems, the reasons for the changes to the ISO contamination standards and explains the workings of AS 4059, the replacement for NAS 1638. It goes on to detail the latest changes to this standard.

• 한국항공우주학회지
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• 제42권9호
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• pp.773-778
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• 2014

항공기에 있어서 통신장비는 조종사간 내부통신과 타항공기 및 지상관제탑과의 외부통신을 가능케하는 장비로서 임무 수행 및 안전에 있어서 매우 중요하다. 따라서 송수신 기능의 구현만으로는 요구되는 성능요구조건을 만족했다고 할 수 없고, 잡음이 없는 맑고 깨끗한 통신품질을 제공해야 한다. 본 논문에서는 T-50 항공기(고등훈련기) 운용 중에 발생된 내부통신 잡음 현상에 대한 원인을 분석하고, 이 현상에 대한 개선을 위해 Single Point Ground 설계 개념을 적용한 결과를 정리하였다. 또한 설계 개선사항에 대한 검증을 위한 비행시험 결과를 함께 기술하였다.

• 항공우주기술
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• 제5권2호
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• pp.248-257
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• 2006

무인기의 수요가 많아지고 기술이 발달되면서 가까운 장래에 무인기가 유인기 공역에 진입할 날도 머지않았다. 무인기는 조종사 없이 비행이 이루어지므로 사전에 장애물을 탐지하여 자동회피하는 장치가 반드시 필요하다. 이에 따라 유인기가 사용하는 충돌회피장치인 TCAS II의 동작원리와 인터페이스틀 분석하여 무인기에 사용여부를 확인하고 문제점을 판단한다. 결론적으로 TCAS II의 탑재 방향성 안테나는 정밀하지 못하여 표적의 정확한 방위각을 FCC에 제공하지 못하므로 단독으로 사용할 수는 없고 표적의 정확한 방위각을 제공하는 타 장비와 함께 활용되어야 한다.

• 드라이브 ㆍ 컨트롤
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• 제9권3호
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• pp.23-28
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• 2012

In this study the flow rate-to-pressure difference characteristics of short-tube type damping orifices for an aircraft door damper were investigated by CFD analyses and experiments. As the design parameters of the damping orifice its diameter, inlet and outlet angle, tube length and the viscosity of the working fluid were taken into consideration. The results showed that the discharge coefficient of the orifices are dependant on the inlet and outlet angle and the oil viscosity, while their length plays an little significant role. Although the short-tube type damping orifice was employed to induce a turbulent flow, their discharge coefficient decreases rapidly as the oil viscosity gets higher than 50mm2/s. Therefore, in order to determine the orifice size, satisfying the working temperature range of the door damper, the oil viscosity as well as the friction force on the damper piston should be kept within proper values. For the verification of the CFD analysis results the actual performance of a door damper was measured and compared with them.

• 한국항공운항학회지
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• 제16권1호
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• pp.18-28
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• 2008

The purpose of this study is leading to prevent the major causes of commercial-aviation fatalities about controlled-flight-into-terrain(CFIT) in approach-and-landing accidents. The paper of major analysis for controlled flight into terrain(CFIT) was Guam accident, Mokpo accident and Gimhae accident in commercial transport-aircraft accidents from 1993 through 2002. CFIT occurs when an airworthy aircraft under the control of the flight crew is flown unintentionally into terrain, obstacles or water, usually with no prior awareness by the crew. This type of accident can occur during most phases of flight, but CFIT is more common during the approach-and-landing phase. Ninety-five percent of the Guam accident, Mokpo accident, and Gimhae accident where weather was known involved IMC, fog, and rain. The paper believed that prevention for CFIT accident was education and training for flying crew and upgrade for equipment such as EGPWS, and need more research for professional organizations of airlines, and accomplishing precision approaches should be a high priority.

• 한국항공우주학회지
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• 제45권6호
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• pp.490-497
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• 2017

회전익 항공기에 적용된 주륜완충장치는 착륙계통 장비로서 조종사의 임무 수행에 핵심적인 장비이다. 주륜완충장치는 항공기가 지상에 있을 때 동체를 지지해주며 착륙 시 지면으로부터 오는 충격을 흡수함으로서 조종사 및 병력의 작전 운용능력을 만족시킨다. 그러나 A 항공기 지상 계류 시 항공기의 비대칭 현상과 누유 현상이 발생되었다. 따라서 본 논문에서는 주륜완충장치의 운용 시 발생한 결함사항을 발생원인 별로 분류하고, 각 지적사항에 대한 고장탐구 수행과정을 정리하였다. 또한, 고장탐구 내용을 바탕으로 도출한 설계개선 사항과 개선사항에 대한 검증 결과를 함께 기술하였다.

• 한국군사과학기술학회지
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• 제23권1호
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• pp.59-65
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• 2020

Many technologies are being studied to reduce the RCS(Radar Cross Section) of stealth aircraft. Most RCS-reduction technlogies correspond to platforms. It is important to identify factors that RCS performance through simulation analysis of aircraft Mounted equipment. In particular, there are no studies of RCS performance in the radar frequency band when antenna transmit signals are applied. In this paper, the RCS performance variation on the transmit signal on/off of antennas mounted on a stealth aircraft was verified. Antennas were selected for each frequency band and simulated analysis to the RCS performance changes during antenna transmitting signal. Finally, to verify the characteristics of the change in RCS performance, RCS test measurements on the low-profile antenna transmit signal on/off were performed. In addintion, antenna RCS test measurement was performed according to the change of transmit signal power output. As a result, it was confirmed that there is no change in RCS performance when an antenna transmit signal is applied.

• 제어로봇시스템학회논문지
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• 제21권9호
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• pp.888-897
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• 2015

A flight capability to take a terrain following flight near the ground is required to reduce the probability that a fighter aircraft can be detected by foe's radar fence in the battlefield. The success rate for mission flight has increased by adopting TFS (Terrain Following System) to enable the modern advanced fighter to fly safely near the ground at the low altitude. This system has applied to the state-of-the-art fighter and bomber, such as B-1, F-111, F-16 E/F and F-15, since the research begins from 1960's. In this paper, the terrain following system and GCAS (Ground Collision Avoidance System) was developed, based on a digital database with UTAS's TERPRROM (TERrain PROfile Matching) equipment. This system calculates the relative location of the aircraft in the terrain database by using the aircraft status information provided by the radar altimeter and the INS (Inertial Navigation System), based on the digital terrain database loaded previously in the DTC (Data Transfer Cartridge), and figures out terrain features around. And, the system is a manual terrain following system which makes a steering command cue refer to flight path marker, on the HUD (Head Up Display), for vertical acceleration essential for terrain following flight and enables a pilot to follow it. The cue is based on the recognized terrain features and TCH (Target Clearance Height) set by a pilot in advance. The developed terrain following system was verified in the real-time pilot evaluation in FA-50 HQS (Handling Quality Simulator) environment.

• 한국항행학회논문지
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• 제11권2호
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• pp.137-145
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• 2007

본 논문에서의 ADS-B 비행시험은 CDTI상에 목적고도가 제공될 경우 항공교통관제사 및 조종사에게 운영상 어떠한 효과가 있는지를 실증하고자 시행되었다. 또한 이 비행시험은 현 항공교통관제업무 환경에서 ADS-B 운영시험을 하는 최초의 연구이자 향후 우리나라에 ADS-B의 배치를 고려하기 전에 운영상의 실질적인 정보를 제공하기 위한 연구이다. 비행시험을 위해 ADS-B 장비가 탑재된 H 대학교의 항공기 2대가 이용되었고, 충남 태안소재 태안비행장에 지상국이 구축되어, 기 설정된 비행절차에 따라 비행시험이 수행되었다. ADS-B 비행시험 결과 통신주파수 사용횟수 및 주파수 점유시간이 기존의 시스템에 비해 현저하게 줄어듦을 확인하였고, 따라서 항공교통관제사의 업무량(workload) 뿐만 아니라 조종사의 상황인식도 뚜렷하게 개선되어짐을 확인할 수 있었다.