• Journal of Advanced Navigation Technology
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• v.25 no.3
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• pp.256-266
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• 2021

Domestic and foreign studies point to human factors as the main cause of unmanned aerial vehicle accidents, and HFACS is introduced as a technique to effectively analyze these human factors. Until now, domestic and foreign cases of analyzing the human factors of unmanned aerial vehicle accidents using HFACS were mainly targeted by military unmanned aerial vehicles, which can be used as an objective cause identification and similar accident prevention tool. In particular, identifying the focus of HFACS application considering the performance and operation conditions of domestic civilian unmanned aerial vehicles is expected to greatly help identify the cause and prevent recurrence in the event of an accident. Based on HFACS version 7.0, this study analyzed the accident investigation report data conducted by Korea Aviation and Railway Accident Investigation Board to identify the focus of HFACS application that can be used for domestic civilian unmanned aircraft accident investigations.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.16-23
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• 2023

The aircraft fuel system performs a number of functions such as supplying fuel, transferring fuel between fuel tanks, and measuring the amount of residual fuel in each fuel tank. Since it is a direct cause of fire hazard in crash incident, it is a must to improve survivability of crew members by designing the airframe to tolerate expected crash impact. The civil aviation authority requires intensive verification of the fuel system design to determine precise application of the airworthiness requirement. Research activity on airworthiness certification criteria and verification scheme is still insufficient, although it has a significant importance. In this paper, as part of a study to improve flight safety by developing guidelines for demonstrating fuel system crash resistance, analysis results of fuel system crash-related airworthiness certification standards, verification scheme, and cases study applicable to military rotorcraft have been reviewed.

• Journal of the Korea Institute of Military Science and Technology
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• v.1 no.1
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• pp.114-127
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• 1998

A user friendly computer code(EMCOMST; Electro-Magnetic response for COMposite STructures) was developed which provides with computations of the response characteristics such as reflectance and transmittance to the incident wave angles, frequencies, composite thicknesses, ply orientations, and types of backplate as the linearly polarized transverse electro-magnetic wave is emitted to the advanced composite structures. In this investigation were reviewed the electromagnetic characteristics of the continuous orthotropic fiber-reinforced organic matrix composites with or without ferrite fillers, which are actively applied to low-weight and high-strength aircraft structures. Also were calculated the response of the three layered compound structures which have appropriately stacked above-mentioned materials as transmitting layer, absorbing layer, reflection layer, respectively under the specific thickness constraints for mechanical strength design requirements. For the composite structures presented in this study, minimum reflectance value less than -5㏈ can be obtained in the frequency range of 4 to 12 ㎓. In addition, analysis of structures attached isotropic radar absorbing materials(RAM) is facilitated by putting the material properties in the material input card entries adequately.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.4
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• pp.417-423
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• 2012

Radar Cross Section(RCS) is a measure of how detectable an object is with a radar. A larger RCS indicates that an object is more easily detected. Informally, the RCS of an object is the cross-sectional area of a perfectly reflecting sphere that would produce the same amount of reflection strength as the object in question would. In order to estimate RCS of aircraft weapons the external surface is modeled as a collection of simple shape elements. And the overall RCS is estimated as a vector sum of configuring elements' cross-sections which are well known given by analytic formulae. A RCS estimation code is developed for a typical shape of Air-To-Surface bombs and missiles. Size of weapons and location of fins are implemented in the code in addition to the presence of canards. The ability to predict radar return from flying vehicles becomes a critical technology issue in the development of stealth configurations. This simplified method of RCS estimation is known to be fast and accurate enough in an optical region of high frequency incident radio wave.

• International Journal of Safety
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• v.10 no.2
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• pp.21-26
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• 2011

In 2001, an independent official board was constituted in Japan to investigate aircraft and railway accidents. In the past 10 years, many accidents and serious incidents have been investigated and these official reports were published by the board, on which the author had sat for 9 years as boarding member. In the interim, there were several train disasters which mocked our trust in railways and also many apparent trivial incidents. In recent years, serious incidents, which a door of running rail cars opens suddenly with some trouble, happen 2 or 3 times in a year. For the past 10 years, such incidents have happened 14 times and 13 cases of them were closed by the board mentioned above. In these 13 cases, no one fell off the rail car, so that the death toll was none luckily. In this paper, these 13 serious incidents are picked up among all the reports published by the board and outlined using some tables. Especially, fall accidents of passengers are discussed mainly from the view point of impact force and duration time. Then, the equation of HIC (Head Injury Criteria) and the risk curves in terms of the HIC are dealt with properly.

• 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 Advanced Navigation Technology
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• v.22 no.4
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• pp.279-287
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• 2018

Flight tests for aircraft development and certification have higher air accidents risk than other aerospace industries. Accordingly risk identification necessary for risk management in the safety management system is a very important factor in preventing similar air accidents during flight tests. But internationally issued accident statistics are usually confined to commercial transport aircraft and they do not reflect characteristics of flight tests, also databases to hazards identification during flight tests are not established or available in Republic of Korea. Therefore, we identified flight test procedures and traced the major causes of aviation accidents based on the statistics and preventive materials for risk management which were issued by international organizations and advanced countries of aviation. A total of 312 final reports classified as flight test among air accident/incident database held by U.S. NTSB were researched and about 200 flight test hazard were identified. The results of this study will be used as basic data for establishing the safety management system of the national comprehensive flight performance test site.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.1
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• pp.45-85
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• 2005

The purpose of this paper is to examine the concept of "accident" under the Warsaw system including the Warsaw Convention for the Unification of certain Rules for International Carriage by Air of 1929 and the Montreal Convention of 1999. Most leading case on this subject is Air France v. Saks(470 U.S. 392 (1985)). In the Saks case, it was held that the definition of an accident must be applied flexibly, and most courts have adhered to the definition of accident in Saks case, the application of accident has been less than consistent. However, most cases have held that if the event is usual and expected operation of the aircraft, then no accident has occurred. Courts have also held that where the injury results from passenger's own internal reaction to the usual, normal, and expected operations of the aircraft, it is not caused by an accident. As the Warsaw drafters intended to create a system of liability rules that would cover all hazards of air travel, the carrier should liable for the inherent risks of air travel. It is right in that the carrier is in a better position than the passenger to control the risks during air travel. Most US courts have held that carriers are not liable for one passenger's assault on the other passenger. The interactions between passengers are not part of the normal operations of the aircraft and are therefore not covered by the word "accident" under Art 17 of the Warsaw Convention. It is regretful that the Montreal Convention did not attempt to clarify the concepts of accident in itself. In the light of an emerging tendency to hold the air carrier liable for occurrences that do not exactly go to the operation of the aircraft, it is desirable to regulate that the carrier is liable for an "event" instead of an "accident" in accordance with the Guatemala City protocol.

• The Korean Journal of Air & Space Law and Policy
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• v.28 no.1
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• pp.115-157
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• 2013

Some contracting States of the Convention on International Civil Aviation (commonly known as the Chicago Convention) issue FAOC(Foreign AOC and/or Operations Specifications) and conduct various safety audits for the foreign operators. These FAOC and safety audits on the foreign operators are being expanded to other parts of the world. While this trend is the strengthening measure of aviation safety resulting in the reduction of aircraft accident, it is the source of concern from the legal as well as economic perspectives. FAOC of the USA doubly burdens the other contracting States to the Chicago Convention because it is the requirement other than that prescribed by the Chicago Convention of which provisions are faithfully observed by almost all the contracting States. The Chicago Convention in its Article 33 stipulates that each contracting State recognize the validity of the certificates of airworthiness and licenses issued by other contracting States as long as they meet the minimum standards of the ICAO. Consequently, it is submitted that the unilateral action of the USA, China, Mongolia, Australia, and the Philippines issuing the FOAC to the aircraft of other States is against the Convention. It is worry some that this breach of international law is likely to be followed by the European Union which is believed to be in preparation for its own unilateral application. The ICAO established by the Chicago Convention to be in charge of safe and orderly development of the international civil aviation has been in hard work to both upgrade and emphasize the safe operation of aircraft. As the result of these endeavors, it prepared a new Annex 19 to the Chicago Convention with the title of "Safety Management" and with the applicable date 14 November 2013. It is this Annex and other ICAO documents relevant to the safety that the contracting States to the Chicago Convention have to observe. Otherwise, it is the economical burden due to probable delay in issuing the FOAC and bureaucracies combined with many different paperworks and regulations depending on where the aircraft is flown. It is exactly to avoid this type of confusion and waste that the Chicago Convention aimed at when it was adopted in 1944. The State of the operator shall establish a system for both the certification and the continued surveillance of the operator in accordance with ICAO SARPs to ensure that the required standards of operations are maintained. Certainly the operator shall meet and maintain the requirements established by the States in which it operate. The authority of a State stops where the authority of another State intervenes or where the former has yielded its power by an international agreement for the sake of international cooperation. Hence, it is not within the realm of the State to issue FAOC towards foreign operators for the reason that these foreign operators are flying in and out of the State. Furthermore, there are other safety audits such as ICAO USOAP, IATA IOSA, FAA IASA, and EU SAFA that assure the safe operation of the aircraft, but within the limit of their power and in compliance with the ICAO SARPs. If the safety level of any operator is not satisfactory, the operator could be banned to operate in the contracting States with watchful eyes until the ICAO SARPs are met. This time-honoured practice has been applied without any serious problems. Besides, we have the new Annex 19 to strengthen and upgrade with easy reference for contracting States. We don't have no reason to introduce additional burden to the States by unilateral actions of some States. These actions have to be corrected. On the other hand, when it comes to the carriage of the Personal or Pilot Log Book, the Korean regulation requiring it is in contrast with other relevant provisions of USA, USOAP, IOSA, and SAFA. The Chicago Convention requires in its Articles 29 and 34 only the carriage of the Journey Log Book and some other certificates, but do not mention the Personal Log Book at all. Paragraph 5.1.1.1 of Annex 1 to the Chicago Convention even makes it clear that the carriage in the aircraft of the Personal Log Book is not required on international flights. The unique Korean regulation in this regards giving the unnecessary burden to the national flag air carriers has to be lifted at once.

• Journal of Advanced Navigation Technology
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• v.20 no.2
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• pp.141-147
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• 2016

Stable and reliable air traffic service is required for users (aircraft pilot, air traffic controller, airlines and public) through enhancing capability related to airport operation and continuously improving air navigation system. ASMS (air navigation service provider (ANSP) safety maturity survey) is to determine the level of management and safety requirement such as organization, risk, policy, process, training and environment in Air traffic service field. We designed and developed the survey (26 study areas of management part and 23 study areas of safety part) considering global best practices (Eurocontrol and FAA) and customizing domestic circumstances with quantitative level assessment regarding management and safety issue of Air navigation system. The survey enables the performance of Air navigation system to enhance and prevents from occurring accident or incident. Therefore, we provides best information with users as well as high quality Air traffic service.