Aircrafts Lightning Strike Protection with Air France Flight 447 - Case Study Example

Air France Flight 447 Discussion Lightning strikes have caused several fatal accidents in aircrafts. Certificated FAA aircrafts are struck by lightning once or even twice a year. However, it is not possible to know the amount of power that strikes the aircraft. Although modern aircrafts are equipped and made in such a way that they can pass through lighting, the nature can result and cause disaster anytime on aircrafts as it is unpredictable. Large commercial jets like Flight 447 and general aircraft have been struck by lightning and thunderstorms which resulted to their fatal crash. Modern jets may not be considered safe although made of composite materials because their operating and flying system are made and depend on electronics. However, lighting strikes seeks for metals paths that may be available on the aircraft structure towards control and electronic system. An increasing reliance on materials made from composite materials in the construction of aircraft creates the potential for extra problems. This is mainly because the composites can allow airplane electrical circuits and lightning connection. Aircraft structures made of composite materials in most occasions provides a direct connection of lightening current effects to the control system of the aircraft. It has been noted that the more the composite materials in the aircraft components, the more the risk an aircraft is exposed to lightning according to Professor Rakov. Composites on the aircraft bodies do not conduct away the excessive electric current amounts as well as electromagnetic forces instead it tries to find electrical paths that may be available and it is only electronics system. This is an exact situation that took place in the Air France Flight 447 that was flying through a region with heavy storms or thunderstorms with excessive amounts of current or powers. This eventually leaked into control system resulting to its failure1. According to NASA, it researched that aircraft itself produces lightening itself in areas where is no lighting activity until aircrafts gets there. NATA proved that lighting strikes are not at any point related to ambient temperature or altitude in which aircrafts fly but on the thunderstorm regions more often on the upper area of the thunderstorm region. NASA proved that heaviest turbulence and rainfall do not contribute greatly to the accidents associated with lighting but rather the rainfall and turbulence accompanied by heavy thunderstorms. Air France Flight 447 crashed on an area that had intensive thunderstorms; this provides good evidence that lightening may likely be the main reason behind the accident. Aircraft’s last minutes were spent through thunderstorms and turbulence activity for approximately 121 km. basing our argument on NASA’s research; this might be main cause of accident behind the accident or crash of 447. Air France Flight 447 was passing through an area regarded as ITCZ (International Convergence Zone). International Convergence Zone is an area surrounding the earth near intersection of the earth’s surface with the plane perpendicular to the axis of the earth of rotation and it contains centre of the mass of the earth. International Convergence Zone is an area where winds originating from southern and northern hemispheres meet. This creates unpredictable patterns of weather with violent thunderstorms and inactive calms. The International Convergence Zone region is formed by vertical motion appearing from thunderstorms convective activity driven by solar heating that draw in air effectively. In the north eastern and north Atlantic pacific oceans, tropical waves usually move along the International Convergence Zone resulting to increased thunderstorm activities and under weak vertical wind shear. This eventually results to clusters of thunderstorms. These were the conditions that were prevailing when the Air France Flight 447 was flying through that region and definitely thunderstorms or lighting storms struck on it making it crash. The storms or lighting storms at this region are so intense that they may have been having thermal effects that may end up melting the thins skins of composite or melt aircraft system’s control wires and eventually failing the whole structure of aircraft and consequently the crash2. Lighting in this region may lead to production of thermal effects with temperature of more that the sun3. Although a lot of research had been done on how to develop an aircraft resistance to lighting, sometimes it becomes difficult to control some more extensive nature like severe storms. Incorporation of composite as well may not have been able to reduce and avoid that accident. The storms that occur at International Convergence Zone are regarded to be more dangerous especially to aircrafts. Their power amount was higher to be controlled by components incorporated in the aircraft like the use of composites. Storms may have gotten through some gaps to electronic system of the Flight 447 and eventually the failure of operating system resulting to failure. Air France Flight 447 was a planned commercial flight to Paris from Rio de Janeiro. This commercial flight crashed on 1 June 2009 into Atlantic Ocean where it killed all people in board who included 216 passengers and 12 members of crew. The aircraft registered as F-GZCP WAS AN Air France Airbus A330-200. As the aircraft approached Brazilian radar surveillance edge over the Atlantic Ocean, the last contacts were received. Some minutes later, several automatic radio messages were received in air traffic controllers which indicated several warnings and problems. At the moment the aircraft was flying, the weather was moderately turbulent with intensive thunderstorms in the area. After meteorological analyzed the surrounding the path of the flight, it showed a mesoscale convective system. This extended to an attitude of 15 km; 9.5 mi (50,000) above the Atlantic Ocean before disappearance of Flight 447. Images from satellite that were taken near the incident of accident indicated that the aircraft might have encountered thunderstorms that were having moderate turbulence. Weather conditions detailed analysis for the flight indicated possibility of aircraft’s last 12 minutes to have been spent through thunderstorms and turbulence activity for approximately 121 km. This meant that there was high possibility of being subjected to rime icing or even graupel or clear ice. Imagery from satellite loops from the CIMSS made it clear that the plane was coping with several storms. Storms and thunderstorms are associated with lightening which adversely affect aircrafts and this is the main reason behind this accident that took place on Flight 447. It is known that after final oral contacts with the aircraft, it went through an area of numerous thunderstorms along the Intertropical Convergence Zone. All modern aircrafts are well equipped with the (ACARS) Aircraft Communications Addressing and Reporting System. AF447 was programmed such that it capable of transmitting its position approximately after every ten minutes through ACARS4. Soon after the last verbal communication with Air Traffic Control about 560km Natal’s north east side, there is likelihood that aircraft traversed into a region of powerful deep convention that had formed a thunderstorm broad band along Inter-tropical Convergence Zone (ITCZ). Turbulence in the environs of the storms that were developing rapidly might have contributed to the occurrence of the accident. Flight AF447 send twenty six messages of which twenty four messages were received near the time at which the accident occurred. This was on 1st of July 2009 between 2h 10 minutes and 2 h 15 minutes. The two messages that were received first on the day before incident were received at 22:45 and they were related to fault message. It represented a difference in lavatory configuration between the aircraft and associated aircraft system. Other messages were received on time of incident at 2:10. The first message was received on 2h 10m 10s which was explained as the autopilot being disconnected by pilot by the use of the available facility to control the aircraft manually or by the automatic system on the aircraft control system. Second message was received at 2h 19m16s which was explained as unavailability of the reaction to system of wind shear detection. The fifth message received at 2h 10m 41s which indicated a disconnection of auto-thrust either by moving the throttle control levers or pressing the provided button by the pilot. From ninth message, this was a clear indication that the flight had been affected by lightening or thunderstorms. At 2h 1m 21s, message indicated and concluded that the aircraft’s rudder deflection was jammed till the slate extension was given. None of the pilots of the flight control system were able to deflect the rudder. The tenth message was about Electronic Flight Control System 1 and 2 maintenance status. At this moment the flight control systems were almost destroyed. The eleventh message indicated that the Flight Path Vector by both the first officer and the pilot were selected and did not activate. The twelfth message continued to indicate the destruction of the control system or electronics by the lighting. The message was described that the flight control systems rejected the air data reference. It continued to define the unpredictability between two remaining air data reference. The thirteenth message was an indication of major error as it indicated that Flight Control Primary Computer stopped operating mainly due to avionic system major failure of the aircraft. The flight controls primarily computer stopped working exactly after 13th message. The fourteenth message indicated that the flight control secondary computer was completely shut down. This was an indication of electricity failure that occurred during the flight. Lightening or thunderstorms are closely related with failure of electricity or electronic systems. This then gives a clear indication that the aircraft was affected by the lighting when on the flight. This was a clear indication that the lighting had interfered with control and electronic system of the flight leading to total failure of the control and all electronic system5. Work Cited American Meteorological Society. ‘Meteorological and geoastrophysical abstracts’, American Meteorological Society Journal, Vol. 48, Issue 7, 1997, pp. 35-45. Campbell, F. Manufacturing Process for advanced composites. McGraw Hill, New York, 2004. Khurana, K. AVIATION MANAGEMENT: Global Perspectives. Global India Publications, New Delhi, 2009. Peter Burkill & Maria Burkill. Thirty Seconds to Impact. Author-House Press, Michigan, 2010. Uman, M. A., Rakov, V. A., Schoene, J., Rambo, K. J., Jerauld, J., & Schnetzer, G. H. ‘Close Lightning Electromagnetic Environment for Aircraft Testing’, Journal of Aerospace, Vol. 21. Issue 5, 2001, pp. 312-319. Read More