Why Windows of Airbus Airplanes Do Not Affect by the High Voltage Lighting in the Sky - Research Paper Example

TESTING AND ANALYZING THE WINDOWS OF AIRBUS AIRPLANES High Voltage Lightning in Sky Lightning in the sky is due to heavy electrostatic discharges taking place in charged regions within a cloud or between the adjacent clouds. These charged regions produce lightning flashes in order to equalize the concentration of charge. Commonly three types of lightning flashes are much common, named as: Intra-cloud Lightning One Cloud to another Cloud Between Cloud and the Ground Amongst these the most dangerous and critical lightning is the one between the cloud and the ground as it may directly influence the living organisms or can even affect the property, whereas, the rest of the two are dangerous for the flying planes and crafts. Therefore, while designing and developing plane preventive measures are taken to cope with such unpleasant situations before time. Dangers of High Voltage Lightning High voltage lightning within the atmosphere(Naidu and Kamaraju); negatively affect the planes and birds during flight. Below is the exhaustive list of dangers suspected as a result of high voltage lightning. Lightning Stroke Lightning strokes result in the production of immense heat energy and high intensity magnetic forces. This heat energy is directly produced at the surface of the body which is in contact with the lightning strike. The extent of this generated is too high to vaporize the sap of a tree if it travels across it. This vaporization would result in the generation of immense steam which may result in the bursting of the tree trunk. If this steam is allowed to pass through soil, it may cause plasma channels to melt down forming fulgurites. Any sort of contact with humans or other loving things may even result in spontaneous deaths. Therefore, while designing sophisticated systems, lightning protection systems needs to be introduced in order to keep the system protected in unpleasant situations as well. Thunder Lightning is always accompanied by a thunder sound. This is not only a sound we hear but it is actually a very dangerous compression wave which is high in intensity as well as speed and can badly affect anything during its flight. Chemistry of thunder is that the electrostatic discharge produces lightning which is having high temperatures that heats the air and converts it to plasma. This process takes place along the discharge channel. Production of plasma raises the pressure within the cloud area resulting in sudden expansion of molecules outwards the area. This expansion is accompanied by the production of shockwave with immense energy. This energy can really affect the flight of the plane flying through the cloudy area. High Energy Radiation Lightning is one of the most common source of natural disaster and fatalities after flood and each year hundreds of people lose their life due to high intensity bolts produced by lightning(VanScoy). These electric bolts or surges of lightning, besides directly harming humans, can also affect living beings by the generation of high energy flashes of gamma rays. Conversion of electricity to gamma rays is possible as a result of Einstein’s mass energy relationship according to which energy can be transformed to mass and vice versa(Choi). The gamma rays generated as a result of lightning exist for a millionth part of a second and are having extensive energy and are named as terrestrial gamma rays flashes which are produced as a result of intra-cloud lightning arcs. These lightning surges which are accompanied by the production of high intensity gamma rays are really dangerous for people travelling in airplanes as these are usually produced in the same zone in which airplanes and passenger planes fly. These adverse radiations are generated below cruising altitudes and sometimes planes have to pass through these adverse environmental situations to reach to their destination. In such circumstances the airplane is more like a best electricity conductor due to the metallic body also the body of the plane cannot be grounded while it is on flight, this adds more danger to the flying plane(LufthansaTechnik). Also another danger associated with terrestrial gamma rays is the production of high intensity X-rays. If a person remains exposed to these rays while lightning, he is supposed to be exposed to a full body CT scan which may harm the normal processes taking place within the body of people who are already at the border line of high intensity absorption(FloridaInstituteofTechnlogy). Affect of High Voltage Lighting on Airbus Windows Airbuses and other aircrafts are manufactured by extensively making use of Aluminum and its alloys. These alloys are used for the manufacturing of body and internal structures of aero planes and are exclusively being used in aerospace due to its lightweight, ductility and durability. Also the metal is having anti corrosive properties which make it suitable to be used in the manufacture of airbuses which have to fly over different climatic conditions. Although Aluminum is not a very good conductor of electricity but the extent of electric charge lightning carries is too high that it may even damage Aluminum if preventive measures are not taken. The high electric discharge during lightning results in the generation of intense amount of air currents on the plane body. These peak currents are then induced into the wire harnesses on board resulting in malfunctioning of sensitive and critical electronics on the navigation panel and other parts of electronic systems of air bus(Zhang and Huang). Figure 1: Pictorial view of damaged area due to lightning of 100KVA on the air bus body During lightning when the light strikes on the surface of the plane, the arc gets unstable due to the effect of aerodynamics. This results in the deformation of the arc resulting in extensive increase in the electric field within the gap between the airplane and the source of lightning. The extent of lightning increases with the increase in the length of the arc and also the distance between the source and airbus surface. The extent of produced electric field when reaches close to or crosses the limit of critical field strength, a strong dielectric breakdown occurs within the air gap above the surface of the airbus(Kumar, Kumar and Singla). Figure 2: Swept Stroke taking Place on the Surface of the Plane Material and Properties of Airbus Windows Generally airplanes make use of Plexiglas(Evonik) to manufacture their windows; other similar compounds can also be used in the manufacturing of windows depending upon the application. In jet planes cockpit windows are composed of three layered acrylic to provide extra strength and power to the windows. In all airbuses cockpit windows are given extra strength as they are more prone to deadly accidents including striking of the birds in flight and the upcoming storms and hail(AeroPlastics). Also the windows are provided with triple protection system including the essence of glass with plastic providing durability and anti-icing/freezing property induced, to provide with better visibility to the pilots. Also the window glass is usually covered from the outside with a material from which rain drops do not stay on the glass rather they are easily shed off thus providing clear view to the pilots. It can also be observed that the windows of the airplane are usually kept smaller in size. This proportion is maintained to ensure the fact that the pressure inside the airbus (fuselage) is kept higher as compared to the one at the outer side of the air bus. To keep the internal pressure higher, there is a strong need of extensively durable walls around the airbus. Keeping the window size larger weakens the outer walls therefore; they are kept smaller and behave extensively well during lightning as well due to non-conductive nature and durability. As far as the windows of cockpit are concerned these are huge enough to provide clear view of all happening in front of the pilot within the atmosphere. Also the material of these windows is not the one provided in fuselage. It is more durable and fine but expensive. If the window of the airplane gets broken it does not harm the passenger because the pressure maintaining system is too efficient to overcome instant pressure changes resulting due to removal of window(Dimino). Conductivity of Airbus Windows Airbus windows are usually composed of Plexiglas, specialized material for fuselage window construction. This material provides with highest grade transparencies with having good quality optical characteristics(Transparency_Bulletin). The material is also having good ageing resistance with the good protection against UV radiations. This property allows Plexiglas to be an ideal material to be used for airplane windows. As the airplane flights at higher altitudes, it is more prone to UV radiations specifically from sun which may adversely affect the passengers within the plane(Banks), therefore, selection of Plexiglas as the material for airbus windows results in the best outcomes as far as passengers safety is concerned. Not only this, but this material is really good to be used in lightning, providing maximum security against high intensity gamma rays being produced as a result of inter cloud lightning. As the material is made up of high class plastic made of acrylic, therefore it provides maximum protection against conductivity of lightning charges through the plane. This provides protective shield to the passengers against harms resulting from electric shocks. The selection of Plexiglas as a material to be used for the airbus windows is good enough as it is too light to be used in aerospace products. This material also provides excellent conductivity against glazed lightning and acts as a good anti-glare agent resulting in providing comfort ride to the passengers. Other than the material of windows, the airplane is overall protected against lightning. This is done by making use of aluminum or aluminum alloys(Total_Materia) in the manufacturing of airbuses. Airplanes and buses are prone to lightning and other unpleasant situation usually at the points of nose, engine cowlings, wingtips, and the vertical tail tip(Chemartin et al.). Lightning usually affect the entering and exiting point on the planes and these key locations act as entrance and exiting points on the air bus surface. The shape of these components provides greater increase in the strength of electric field and the charges get concentrated at these points. Therefore, nose cone is usually made up of composite material like carbon fiber so that it might not interact with the radar signals and also affect due to the lightning surges is reduced to its minimum. Although aluminum provides maximum resistance but in case of high voltage lightning it is being adversely affected resulting in air crash in 1963. After that preventive measures are taken against this issue. The first step taken in this regard was the development of nonconductive materials. This material was first introduced into the fuselage of the air bus. The whole fuselage was constructed from carbon fiber with an essence of metal thus providing resistance to lightning crashes. The metal placed in the carbon fiber mesh of fuselage provides with the ability to bypass lightning surges from the clouds as the airplane cannot be grounded to earth during flight. Conclusion Airplanes are made to perform in harsh weather conditions and also the environment in which they fly is not favorable for the transportation of ordinary metal based vehicles. They are made non-magnetic and non-conductive to provide security to the person travelling by planes. Aluminum alloys have been used from decades as the material for the construction of the airplane but major focus is needed to be done on the manufacture of non-conductive composite materials to be used for the construction of windows and fuselage. Plexiglas is considered to be the most accurate material for airbus windows ass it provides security to the passengers from intense gamma rays produced as a result of lightning. This material has been tested to provide maximum flexibility to absorb shocks exerted by the outside environment. Windows are made not too big in order to easily maintain higher internal pressures within the plane’s fuselage without experiencing any unpleasant situation. 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