• Journal of Aerospace System Engineering
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• v.13 no.6
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• pp.60-69
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• 2019

Companies around the world are actively developing Personal Air Vehicle (PAV) to solve the serious social problem of traffic jams. Airworthiness certification for PAV is required, since it is a manned vehicle. As with aircraft, the critical threat to the safe operation of PAV is lightning strike with strong thermal load and magnetic fields. Lightning certification issue also remains important for PAV, since there are still insufficient development of PAV-related lightning certification technologies, guidelines, and requirements. In this study, the SAE Aerospace Recommended Practice (ARP), an international standard certification guideline recognized by the Federal Aviation Administration (FAA), was analyzed. In addition, the guideline of lightning certification was applied to a PAV. The impact of lightning on PAV was also analyzed through computational software. Finally, the basis for the establishment of the PAV lightning certification guidance was presented.

• Journal of Aerospace System Engineering
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• v.6 no.3
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• pp.13-18
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• 2012

Every 3000 hour an aircraft is stricken by a lightning. Also the lightning damage to the aircraft during flight are continually occurred due to extreme weather phenomena such as global warming. Under the airworthiness standards, the aircraft must be designed to protect lightning. To show compliance for lightning, the test should be conducted by the actual lightning current and voltage waveform for the actual aircraft or parts. After test, structure damage is detected via visual inspection or NDI. Structure substantiation for damage is to show retaining limit or near limit load capability. This is conducted by test or analysis based on test. Thus, the aircraft should retain structural strength to land safely, even though the damage of aircraft fuselage from Lightning strike are occurred.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.286-292
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• 2014

This paper presents the parameters optimization technology for generating the first short stroke lightning current waveform($10/350{\mu}s$) which is necessary for the performance tests of components of lightning protection systems, as required under IEC 62305 and the newly amended IEC 62561. The circuit using the crowbar device specified in IEC 62305 was applied to generate the lightning current waveform. To find the proper parameters of the circuit is not easy because the circuit consists of two parts; circuit I, which relates to the front of current waveform, and circuit II, which relates to the tail. A simulation in PSpise was carried out to find main factors related to the front and tail of $10/350{\mu}s$. The lightning current generator was developed by utilizing the circuit parameters found in the simulation. In the result of experiments, new parameters of the circuits need to be changed because of the difference between the simulation and the experiment results. Using the iterative method, the optimized parameters of the circuits was determined. Also a multistage-type external coil and a damping resistor were proposed to make the efficiency of generation to enhance. According to the result in this paper, an optimized first short stroke lightning current waveform was obtained.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.110-120
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• 2003

As the wooden aircraft in the early times has no way to let lightning flow when lighting flash attaches during flight, the aircraft got damage, or caught fire. Though all metal airplane was developed with an advent of aluminum, a lightning accident still occurred including a fire of a fuel tanks. Eventually, NACA declared problems in 1938, and an artificial lightning test began. III succession, FAA established Airworthiness Requirements for certification. The FAA committed test measures study for the protection of an airplane from lightning to SAE. SAE presented the test current and voltage waveforms that simulating natural lightning, and it is utilized on lightning protection certification of an airplane by public. A lightning effects of an airplane through an analysis of lightning mechanism was made in this technical note. Especially, lightning direct effects on aircraft are analyzed and lightning strike zones are described.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.3
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• pp.251-262
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• 2021

The airworthiness certification of lightning indirect effects becomes an important issue in personal air vehicles (PAVs), which are being actively developed around the world. PAVs are very vulnerable to lightning strikes, because of miniaturization, use of the electric engines, composite materials, and application of unmanned navigation systems. In this study, we first examined various steps of certifications for lightning indirect effects shown in AC 20 136B issued by the Federal Aviation Administration (FAA). We then applied certification guidelines for equipment transient design level listed in RTCA DO 160G Section 22 to PAVs and investigated lightning transient environments inside the PAVs. We also analyzed the aircraft level tests specified in SAE ARP 5416A by using electromagnetic computational analysis software EMA3D. Finally, we analyzed the actual transient level for PAVs and derived the data necessary for conformity certification.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.130-140
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• 2017

Lightning protective design of an aircraft fuel system is closely related to the safety of the flight. Recently, composite material in building an aircraft becomes more important because it can reduce the weight of the aircraft. The composite materials decrease the protection against the effect of lightning. Lightning protective design of metal material aircraft has been researched for a long time and the design technique has been announced widely. However, research on the lightning protective design using composite material aircraft is very limited. In this study, lightning protective design for fuel tank structural component, access cover, fuel filler cap and drain valve in carbon fiber composite material aircraft have been presented. To show the compliance with FAA airworthiness standard regarding the presented protection designs, three steps, including lightning strike analysis, lightning environment analysis and certification test, were conducted in accordance with FAA AC 20-53.

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.45-56
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• 2021

Demand for UAM (Urban Air Mobility) aircraft is rapidly increasing in countries around the world due to the problem of traffic congestion in urban areas. Through research and development, various e-VTOL aircraft concepts are being prepared for commercialization, for which airworthiness certification is required, since it is a manned transportation mode for people to board. Factors that pose a fatal threat to the safe operation of UAM aircraft include lightning strikes that can cause damage to structures and disturb the navigation system, as well as icing that impairs flight stability. Since the current UAM aircraft-related lightning and icing certification technology development is insufficient, there is need to develop appropriate airworthiness certification guidelines. In this study, after analyzing the laws and regulations related to aircraft by the FAA and the EASA, we tried to incorporate the lightning and icing certification guidelines for the UAM aircraft. We also analyzed the effects of lightning and icing on UAM aircraft using computational simulation, and presented the basis for establishing practical guidelines for the certification of UAM aircraft to be adopted in the future.

• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.23-34
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• 2022

Cities around the world are increasing their demand for Urban Air Mobility (UAM) aircraft due to traffic congestion with population concentration. Aircraft with various shapes depending on fixed-wing and propulsion systems, are being prepared for commercialization. Airworthiness certification is required as it is a manned transportation vehicle that flies in the city center and transports people on board. UAM aircraft are vulnerable to lightning and HIRF environments due to the increasing use of composite materials, the use of electric motors, and use of electronic equipment. Currently, the development of certification technology, guidelines, and requirements in lightning and HIRF environments for UAM aircraft is incomplete. In this study, the certification procedures for lightning and HIRF indirect impacts of rotorcraft shown in AC 20-136B and AC 20-158A issued by the Federal Aviation Administration (FAA), were verified and applied to the computerized simulation of UAM aircraft. The impact of lightning and HIRF on ducted fan UAM aircraft was analyzed through computerized simulation, and the basis for establishing practical guidelines for certification of UAM aircraft to be operated in the future is presented.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.48-55
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• 2020

The installation of lightning protection system has recently been increasing, but the amount of damage has still been increasing. In this study, survey (interview) and field conditions were conducted to identify the installation and safety standards of the lightning protection system. it was analyzed that the safety management system is non-existent at the stage of the design, manufacturing and construction of the site lightning protection system, and that the safety inspection of the lightning protection facility is not properly managed. It has been shown that lightning protection systems, that can solve these problems, need to be re-established according to the reality so that safety inspection can be carried out in accordance with safety standards such as management of safety certification products, operation of survey institutions, design, manufacturing, and construction of safety standards at a national level.

• Journal of Advanced Navigation Technology
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• v.18 no.5
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• pp.445-454
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• 2014

In this paper, we introduce measures designed content for RTCA DO-160 F, Section 22 tests performed to verify the effects of indirect lightning and testing process of the test was carried out in the multi-purpose display certification process. This is referred to as indirect effects of lightning capability of an aircraft having electrical electronic equipment failure or damage to bring lightning induced voltages. In order to protect the avionics from lightning indirect effects of these aircraft are analyzing the effects of lightning strikes on aircraft and aircraft systems and interior design needs protection against the threat on their part. In this paper, we introduce RTCA DO-160 F, component selection process according to Section 22 category selection method and the selected level for determining the level of such measures for protection against lightning of multipurpose display for this aircraft. It also introduces the actual test process to confirm that the designed effectiveness of the selected part. We expect a good example of the lightning planned for future development of measures designed avionics through each step of the process introduced this.