scholarly journals Development of a Methodology to Assess Mechanical Impulse Effects Resulting from Lightning Attachment to Lightweight Aircraft Structures

2010 ◽  
Vol 24-25 ◽  
pp. 129-134 ◽  
Author(s):  
C.A. Featherston ◽  
Mark J. Eaton ◽  
S.L. Evans ◽  
Karen M. Holford ◽  
Rhys Pullin ◽  
...  

The effect of lightning attachment to structures and vehicles is a cause of major concern to a number of different industries, in particular the aerospace industry, where the consequences of such an event can be catastrophic. In 1963, a Boeing 707 was brought down in Maryland killing 81 people on board, triggering the improvement of lightning protection standards. However, commercial jets are still struck on average once every 10,000 hours of flight time and between 1963 and 1989 forty lightning related accidents were recorded within the U.S.A alone. The rapid increase in the use of composite materials in aircraft design and the consequent increase in complexity when determining the effects of a lightning strike, has led to new challenges in aircraft protection and the requirement for improved understanding and standardisation.

2021 ◽  
Author(s):  
Mukhtarus Bahroinuddin ◽  
Rosihan Anwar

Abstract Based on NFPA-780, offshore platforms, which made from metal framework of a structure are thought of as "grounded" to the ocean and therefore are not needed to be installed external Lightning Protection System (LPS). PHE ONWJ which located at offshore tropic area has implemented NFPA 80 but still experience lightning hit. It generated fire at vent stack andcause operations interference. So that, the objective of this study is to redesign LPS for tropic area. Firstly, the methodology for this study was conducting literature review from previous researches for lightning protection system at tropic area and researches which underlyingNFPA-780. The literature reviews were focusing on lightning characteristic for tropic area andthe lightning density data from local lighting strike monitors surrounding PHE ONWJ. The result of literature reviews would be the basis of lightning strike event reviews in PHE ONWJ facilities. Subsequently, the authors conducted the equipment layout review using rolling sphere method based on previous lightning strike location. Lastly, Authors proposed the recommendationsfor typical LPS for oil and gas at tropic area. Based on literature reviews,lightning characteristic at tropic area has peak strike current twice the sub-tropic and longer "tail" so that the charge current is larger. Larger the charge current of lightning cause greaterimpact into metal structure that is metal melting. Based on NFPA 780/2011, the offshore platform, which is made by metal, and vessel with minimum thickness 4.8 mm are self-protected. However, based on calculation, with the characteristic of lightning at tropic area, the recommendedminimum vessel thickness is 10 mm. This calculation reinforces the fact that standard of Lightning Protection System in NFPA 780/2011 is not sufficient to be applied in tropic area like Indonesia. After calculating the tropic lightning strike range using rolling sphere method, it isrecommended to redesign lightning protection system for some locations at offshore platform and near shore facilities of PHE ONWJ.The lightning protections system locations and quantities are depending on the area and the needed protected equipment in it.The installation isincluding extended mast terminal, free standing mast, low inductive Double Shielded Down Conductor(DSDC), Lightning Event Counter (LEC), and good grounding system at the platform.


2020 ◽  
Vol 11 (7-2020) ◽  
pp. 66-72
Author(s):  
Liubov A. Belova ◽  

The earth-termination system for towers of ground-based wind turbines in addition to protective and functional grounding provides lightning protection grounding, which is especially important since the wind turbine is susceptible to lightning strikes. If insufficient protective measures are taken, the risk of damage to a wind turbine due to a lightning strike increases. Therefore, a well-thought-out built-in grounding system for wind turbine towers is needed, which would function as necessary and guarantee long-term mechanical strength and corrosion resistance. The configuration of grounding systems for wind turbines is discussed in IEC 61400-24, which deals with the topic of lightning protection for wind turbines, including detailed information on the choice of lightning protection measures and surge protection. It is advisable to create a lightning protection concept at the initial stage of planning a wind turbine in order to avoid later costly repairs and retrofitting.


Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 370 ◽  
Author(s):  
Bogdan Stefan Vasile ◽  
Alexandra Catalina Birca ◽  
Vasile Adrian Surdu ◽  
Ionela Andreea Neacsu ◽  
Adrian Ionut Nicoară

This paper is focused on the basic properties of ceramic composite materials used as thermal barrier coatings in the aerospace industry like SiC, ZrC, ZrB2 etc., and summarizes some principal properties for thermal barrier coatings. Although the aerospace industry is mainly based on metallic materials, a more attractive approach is represented by ceramic materials that are often more resistant to corrosion, oxidation and wear having at the same time suitable thermal properties. It is known that the space environment presents extreme conditions that challenge aerospace scientists, but simultaneously, presents opportunities to produce materials that behave almost ideally in this environment. Used even today, metal-matrix composites (MMCs) have been developed since the beginning of the space era due to their high specific stiffness and low thermal expansion coefficient. These types of composites possess properties such as high-temperature resistance and high strength, and those potential benefits led to the use of MMCs for supreme space system requirements in the late 1980s. Electron beam physical vapor deposition (EB-PVD) is the technology that helps to obtain the composite materials that ultimately have optimal properties for the space environment, and ceramics that broadly meet the requirements for the space industry can be silicon carbide that has been developed as a standard material very quickly, possessing many advantages. One of the most promising ceramics for ultrahigh temperature applications could be zirconium carbide (ZrC) because of its remarkable properties and the competence to form unwilling oxide scales at high temperatures, but at the same time it is known that no material can have all the ideal properties. Another promising material in coating for components used for ultra-high temperature applications as thermal protection systems is zirconium diboride (ZrB2), due to its high melting point, high thermal conductivities, and relatively low density. Some composite ceramic materials like carbon–carbon fiber reinforced SiC, SiC-SiC, ZrC-SiC, ZrB2-SiC, etc., possessing low thermal conductivities have been used as thermal barrier coating (TBC) materials to increase turbine inlet temperatures since the 1960s. With increasing engine efficiency, they can reduce metal surface temperatures and prolong the lifetime of the hot sections of aero-engines and land-based turbines.


Sign in / Sign up

Export Citation Format

Share Document