• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.3
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• pp.81-88
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• 2017

Aircraft maintenance failure doesn't only threaten flight safety but also causes significant economic losses such as flight delays, flight cancellations, air turn backs and diversion and so on. Therefore, the efforts should be made to detect the contributing factors that cause such maintenance failure and eliminate them. In this study, by analyzing factors contributing to system failure using the Maintenance Error Decision Aid (MEDA) model based on stochastic relations between the contribution factors, system failure and events, we will draw a improvement plan to aircraft maintenance defects.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.460-468
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• 2009

The purpose of this study is propose an alternative for flight attendants to acquire equipment that could enhance the ability to adapt in flying conditions. Introducing and acquiring weapon system, such equipments should be deeply considered in multilateral aspects; reinforcements in the overall strategic status in the army, the ramifications that can contribute to military resources, and economic situations in the country. To do this, we first induced several criteria that can be used for evaluating alternatives. After that, we applied the analytic hierarchy process(AHP) approach to putting all factors into considerations in decision making for equipment acquirement. The results of this study are expected to have usefulness in formulating strategies and policies in selecting equipment acquisition alternatives for flight attendants.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.2
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• pp.16-25
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• 2019

While various efforts are being made to ensure aviation safety, air accident rate induced by pilot human factors is still high worldwide. In particular, among pilot human factors, it would be the most important issue for pilots to anticipate and recognize flight environmental factors beyond their control and to make a positive decision making(ADM). In the Republic of Korea Air Force(ROKAF), there were many dizzying experiences induced by bird strike incidents and developed into dangerous moments such as damage to the aircraft and pilots' increased mental stress. It is a matter of serious concern in terms of safety management and human factors to dismiss bird strike incidents as inevitable misfortune due to environmental factors. In 2018, the ROKAF Aviation Safety Agency(ASA) conducted an experimental study to enhance pilots' ADM competence that can anticipate and avoid a bird strike. As the way of the study, 'Bird Strike Preventing Information' had been written and distributed every week by the ASA to flight units in the ROKAF during the period of the study. Through enhanced pilots' perceptual ADM competence, there was a noticeable number of reduction in bird strike incident compared to previous years of the experimental study.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.1
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• pp.66-73
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• 2011

According to U.S. NTSB, from 1989 to 1992, Situation Awareness(SA) was a major factor causing 80% of all aircraft accidents in scheduled airlines. Therefore, the prevention of accidents through effective training in SA became a pivot in aviation safety. Furthermore, during the past 10 years, since all helicopter accidents in Korea were caused by the factors related to SA, an appropriate countermeasure has been required. This study, which uses survey data, examines various factors related to SA that could affect helicopter pilots. Common characteristics of situation awareness factors are that the result from the independent variables which are flight time, duty period and age of a first officer is statistically significant with the result from the independent variables of an instructor pilot's. However, only experience is statistically significant independent variable for factors influencing decision making in emergency situations, but anxiety, expectation and comprehension are not significant.

• Convergence Security Journal
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• v.20 no.4
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• pp.3-12
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• 2020

Although the related regulations or guidelines are not specified in the defense weapon system R&D process, R&D authorities frequently encounter problems that require rational decision-making. If the rational process is not applied in the matter of alternative choice, the project could be disrupted, which can result in longer project periods or more resource provision. In particular, a variety of decision-making methods are needed for test&evaluation of missile R&D. The issue of selecting a test site is one of the representative decision-making problems. If it is needed to determine the priority of multiple sites, Delphi Method and Analytic Hierarchy Process(AHP) will be applied. However, if the input of cost is to be considered, Data Envelopment Analysis(DEA) is more valuable to solve the problem. This paper proposes a solution to handle quantitatively various decision-making problems that can occur in missile flight test, and shows how DEA is applied through a simulated case study of selecting a foreign test site.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.513-520
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• 2004

A steady-state/transient performance simulation model was newly developed for the propulsion system of the CRW (Canard Rotor Wing) type UAV (Unmanned Aerial Vehicle) during flight mode transition. The CRW type UAV has a new concept RPV (Remotely Piloted Vehicle) which can fly at two flight modes such as the take-off/landing and low speed forward flight mode using the rotary wing driven by engine bypass exhaust gas and the high speed forward flight mode using the stopped wing and main engine thrust. The propulsion system of the CRW type UAV consists of the main engine system and the duct system. The flight vehicle may generally select a proper type and specific engine with acceptable thrust level to meet the flight mission in the propulsion system design phase. In this study, a turbojet engine with one spool was selected by decision of the vehicle system designer, and the duct system is composed of main duct, rotor duct, master valve, rotor tip-jet nozzles, and variable area main nozzle. In order to establish the safe flight mode transition region of the propulsion system, steady-state and transient performance simulation should be needed. Using this simulation model, the optimal fuel flow schedules were obtained to keep the proper surge margin and the turbine inlet temperature limitation through steady-state and transient performance estimation. Furthermore, these analysis results will be used to the control optimization of the propulsion system, later. In the transient performance model, ICV (Inter-Component Volume) model was used. The performance analysis using the developed models was performed at various flight conditions and fuel flow schedules, and these results could set the safe flight mode transition region to satisfy the turbine inlet temperature overshoot limitation as well as the compressor surge margin. Because the engine performance simulation results without the duct system were well agreed with the engine manufacturer's data and the analysis results using a commercial program, it was confirmed that the validity of the proposed performance model was verified. However, the propulsion system performance model including the duct system will be compared with experimental measuring data, later.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.3
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• pp.164-170
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• 2024

Since then the aviation industry developed dramatically through the two world wars. As these high-performance aircraft were developed, pilots' training has also changed. While initial pilots' training focused on acquiring the navigation and flight skills necessary for pilots to fly an aircraft, nowadays current training focuses on understanding the system, situation awareness and decision making accordingly, and human factor management among the pilots. The result of pilot training that has achieved continuous change and development is the current Evidence-Based Training. This study aims to determine how situation awareness, problem solving and decision making and workload management, which are core elements of Evidence-Based Training, affect pilot's resilience for safe aircraft operation, and to reflect this in the development and composition of Evidence-Based Training programs to contribute to improving the resilience of individual flight crew members.

• Proceedings of the ESK Conference
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• 1998.04a
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• pp.167-172
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• 1998

Methods of evaluating the physiological activity of the living body are EEG, EOG, Heart rate, and Rectal temperature, etc. In the study of Hagiwara and Araki(1993), they found positive correlations among performance test, physiological measurement, and subjective feeling measurement. Human alertness of pilot directly influences on the flight performance that accomplishes a lot of vigilance task and procedure execution in flight. Accordingly, this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applies. Throughout this experiment using performance thst, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05 .apaprox. 0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is ecpected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.4
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• pp.28-36
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• 2021

Surprise and Startle are often cited as potential or contributing factors in the cause of aircraft accidents because they can negatively affect pilots' situational awareness and decision-making. Accordingly, it is necessary to more clearly understand the effect on flight safety through the psychological and physiological reactions that occur to the pilots. Therefore, this study empirically analyzed the effects of Surprise and Startle on the pilot's psychological and physiological responses using a helicopter flight training device for the first time in Korea. As a result of the analysis, the ratio of recognition of Startle and Surprise, heart rate, and respiration rate showed a high difference between private pilots and commercial pilots. This is analyzed as the difference between long-term flight experience and flight time. In addition to presenting effective information for improving the education and training field of helicopter pilots in the future, it is intended to provide basic data for related research.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.4
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• pp.273-279
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• 2021

Winglets are specialized wingtip devices to reduce induced drag, and they have been installed on Boeing-made aircraft since the 1980s, Airbus has also developed a winglet named 'Sharklet' since 2009 and has started providing them as an option to the A320 Family. The winglet has the effect of improving take-off performance, reducing fuel consumption, increasing payload, and increasing flight distance by reducing the induced drag generated at the tip of the wing. The purpose of this study is to analyze the actual flight data of the sharklet-installed and non-sharklet-installed models of the A321 aircraft to verify the fuel efficiency improvement due to the winglet installation, and to analyze the economic analysis accordingly. Through this, it can be used to determine the winglet installation when introducing an aircraft or to make a decision for upgrading the existing aircraft. To this end, a case study on the aerodynamic characteristics and effects of the winglet installation was conducted, and the economic analysis was verified.