• 한국항공운항학회지
• /
• 제17권4호
• /
• pp.70-75
• /
• 2009

According to the aviation statistics, tail strike incidents and accidents are cyclic. Although many tail strikes occurred during takeoff, these are less than during landing cases. Many cases are related on human factors. In my opinion it is possible to analyze the causes of takeoff tail strikes to some extent. There are major casual factors of tail strike during takeoff such as; (1) Mis-trimmed horizontal stabilizer (2) premature rotation prior to $V_R$ (3) Excessive pitch up rate during rotation (4) Improper use of the flight director. Among these causes improper use of flight director is excluded in this paper because it is recommended that pilot should use flight director after airborne. So I analyzed the other three causes as following. Firstly, because mis-trimmed stabilizer is related to center of gravity(CG), the relationship between stabilizer and CG is reviewed. Secondly, concerned premature rotation prior to $V_R$ I reviewed the background of rotation speed($V_R$) establishment and analyzed theoretically what speed leads to tail strikes. Thirdly, concerning excessive pitch up rate during rotation I analyzed what excessive pitch up rate can decrease ground clearance while using FDR data.

• 한국도로학회:학술대회논문집
• /
• 한국도로학회 2009년도 추계학술대회 논문집
• /
• pp.213-220
• /
• 2009

• 한국항공운항학회지
• /
• 제29권1호
• /
• pp.74-81
• /
• 2021

UAM(Urban Air Mobility) systems have evolved in the form of helicopters in the 1960~1970s, tiltrotors in the 1980s, small aircraft transportation systems in the 2000s, and electric-powered Vertical Take-Off and Landing (eVTOL) in the 2010s; accordingly, the early heliport has evolved to its current form of a Vertiport. Vertical Takeoff and Landing Sites, Vertiports, are important factors for the successful introduction of UAM, along with the resolution of air traffic control (ATC), air security, and noise problems. However, there are no domestic or international installation standards and guidelines yet. Therefore, in this study, installation standards were prepared by referring to domestic and international case studies, ICAO standards, and MIT research papers. The study proposes to establish standards for Final Approach and Takeoff Area (FATO) as 1.5D, 1D for Touchdown and Lift-Off Area (TLOF), and 1.5D for Safety Area (SA). It also proposes to add "UAM Vertiport Installation Standards" to the 「Act on the Promotion and Foundation of Drone Utilization, Drone Act」.

• 한국운동역학회지
• /
• 제17권4호
• /
• pp.157-167
• /
• 2007

The purpose of this study was to analyze kinematic techniques in the woman's 100m hurdle. In order to find the kinematic parameters, a 3-D video system for kinematic analysis-kwon3d 3.1(Kwon3D Motion Analysis Program Version 3.1)-was used. Eight JVC video cameras(GR-HD1KR) were used to film the performance of Lee Yeon-Kyoung at a frame rate of 60fields/s. The kinematic characteristics from the first hurdle to last hurdle were analyzed at the clearing hurdle spots such as distance, velocities, heights and angles. The real-life three-dimensional coordinates of 20 body landmarks during each phases were collected using a Direct Linear Transformation procedure. After analyzing the kinematic variables in the 100m hurdle run, the following conclusion were obtained; Lee Yeon-Kyoung had to maintain constant stride lengths between hurdles and increase takeoff distance before clearance and shorter landing distance after clearance. She also had to hit the correct takeoff point in front of the hurdle and extend the lead leg at the moment of landing in order to minimize the loss of velocity. She had to sprint between hurdles as fast as possible over 8m/s and run powerful first stride and shortened third stride preparing for the following hurdle clearances.

• 한국항행학회논문지
• /
• 제4권1호
• /
• pp.11-22
• /
• 2000

계기비행 시뮬레이터는 조종사들이 실제 비행 시 발생할 수 있는 여러 상황에 대비하여 각종 계기의 판독 및 조작 방법과 비행 절차 등을 숙달하기 위해 사용된다. 그러나 현재까지 개발된 시뮬레이터들은 실제 항공기와 동일한 환경의 구축에 주로 관심을 두었으나 비행에 필요한 다양한 기본적인 임무와 이착륙 절차 등에 관한 체계적 훈련과 훈련 결과에 대한 자동적인 평가 방안에 대해서는 연구가 미진한 실정이다. 따라서 본 논문에서는 계기비행 시뮬레이터에서 비행 중 임무, 이착륙 임무, 항로 비행과 같은 각종 비행 임무의 구현 및 평가 방법을 제시하도록 한다.

• 한국항행학회논문지
• /
• 제27권6호
• /
• pp.804-814
• /
• 2023

인구밀도가 높은 도심지 내에서 비행하게 되는 UAM의 비행경로 하부 및 주변으로는 각종 건축물이 산재하게 된다. 그리고 UAM이 이착륙하는데 사용하는 버티포트는 도심 내의 평지 또는 건축물 상부 등에 위치하게 된다. 이처럼 UAM은 인구밀도가 높은 도심에서 운항하고, 이착륙을 위한 버티포트는 인구밀집지역에 설치됨에 따라 매우 높은 수준의 안전도가 요구된다. 특히 UAM의 안전한 착륙을 위해 최종접근진로에서 버티포트로 접근하는 UAM의 접근상태를 감시하고 접근정보를 제공할 필요가 있다. 이에 UAM 버티포트 최종접근진로 감시를 위해 좁은 부지에 설치가 가능하면서 전자파의 부담이 적다는 장점이 있는 광학장비를 활용하는 기술에 대한 연구를 진행하였다.

• 한국항공운항학회지
• /
• 제21권1호
• /
• pp.23-29
• /
• 2013

This paper presents a tracking filter of radar beacon system (RBS) for automatic takeoff and landing of an unmanned aerial vehicle. The proposed tracking filter is designed as the decoupled tracking filter to reduce the computational burden. Also, an adaptive estimation method of the measurement error covariance is proposed to provide an improved tracking performance compared to the conventional decoupled tracking filter whenever the accuracy of RBS observations is degraded. 100 times Monte Carlo runs performed to analyze the performance of the proposed tracking filter in case of normal operation and degraded operations, respectively. The simulation results show that the proposed tracking filter provides the improved tracking accuracy in comparison with the conventional decoupled tracking filter.

• 한국항공운항학회지
• /
• 제3권1호
• /
• pp.97-105
• /
• 1995

본 연구는 창공-91 항공기의 비행 시험의 일환으로 수행된 것으로, 항공기의 이 착륙 성능 측정을 위한 비행 시험의 절차와 사용된 방법, 자료 처리 절차 그리고 비행 시험 결과에 대해 기술하였다. 본 비행 시험은 FAR 부속서인 Advisory Circular 23-8A 의 비행 시험 절차에 따라 수행되었으며, 측정된 자료를 분석한 결과 설계시에 결정된 창공-91의 성능 자료를 만족함을 보였다.

• 대한임베디드공학회논문지
• /
• 제9권1호
• /
• pp.11-16
• /
• 2014

When it comes to develop flight simulator, HAT (Height Above Terrain) is required to provide altitude information to the pilot who learns how to control an airplane in landing and takeoff situation. However, there might be inconsistent problem between real terrain and simulation information since current implementation of HAT simply depends on center of gravity point on the airplane. To overcome mentioned problem, in this paper, we propose how to obtain more accurate altitude information than existing scheme by making use of HAT and HOT (Height Of Terrain) information of landing equipments according to movement of the airplane. Moreover, we demonstrate the accuracy of the proposed scheme through new flight simulator developed through OSG(OpenSceneGraph) by taking example of terrain information for domestic airport.

• 한국국방경영분석학회지
• /
• 제24권1호
• /
• pp.88-97
• /
• 1998

It is critical to determine the appropriate actions for safe landing of an aircraft in an emergency situation. An expert system can be very useful for this purpose. An expert system specifically for jet fighter $F-\bigcirc\bigcirc$ has been developed. Its knowledge base contains the standard procedures provided by various flight manuals and the expertise of human specialists such as pilots and emergency management personnels. Advising procedures are represented by an IF-THEN format in the developed rule-based expert system. Advises are provided in real time during the entire flight processes of ground, takeoff, inflight, and landing. The developed system would significantly increase the survivability of pilots and aircraft, while decreasing operational costs of emergency management personnels. By modifying the knowledge base, the developed system can also be applied to other types of aircrafts including civilian airlines.