Aviation Pollution

1. Aviation Pollution Eng: Marzouk AL Sharifi

2. أصبحت الطائرات وسيلة للسفر لا يمكن الاستغناء عنها، إلا أنها أيضاً وسيلة مهمة من وسائل التلوث البيئي، وذلك بسبب آلاف الأطنان من غاز ثاني أكسيد الكربون التي تسكبها يومياً وتخرج من عوادمها النفاثة في أضعف نقطة في غلافنا الجوي .  أن الطائرات العملاقة تضخ وحدها في الهواء كميات ثاني أكسيد الكربون تعادل 5 ملايين سيارة مجتمعة في الجزء الأكثر حساسية لغلافنا الجوي. وتوجه اتهامات لشركات الطيران بأنها تستقل الهواء مجاناً وتلوثه في الوقت ذاته؛ وذلك لأنها لا تدفع ضرائب على الوقود الذي تستخدمه في الرحلات. مما ساهم في تبني القوانين لتقليص انبعاثات الطائرات، وإدراجه في منظومة التجارة الأوروبية الخاصة بانبعاثات ثاني أكسيد الكربونيعتقد أن الطيران الجوي مسئول عما يقرب من 13 % من التلوث البيئي، أما نصيبه من تلوث الكون بصفة عامة فيبلغ 3%.  فتلك الانبعاثات التي تصدر على ارتفاعات عالية تضر بالبيئة بصورة كبيرة خلايا وقود الهيدروجين فربما تصبح في يوم من الأيام الوقود اليومي للسيارات والحافلات من دون انبعاثات كربونية، ولكن ضرورة وجود خزانات قوية وثقيلة وحصص خلايا وقود تجعل من الهيدروجين وقوداً خارج الاحتمالات بالنسبة للطائرات. 

3. Air quality Aircraft engines generally combust fuel efficiently, and jet exhausts have very low smoke emissions. However, pollutant emissions from aircraft at ground level are increasing with aircraft movements. In addition, a large amount of air pollution around airports is also generated by surface traffic. The main pollutant of concern around airports is nitrogen dioxide (NO2). NO2 is formed by nitrogen oxide (NOx) emissions from surface traffic, aircraft and airport operations.  PM2.5 is also of concern, since particulate emissions from jet exhausts are almost all in this fine fraction. NOx in the lower atmosphere contributes to the production of ozone; ozone in the lower atmosphere is a pollutant, and contributes to global warming. Nitrogen oxides from high-altitude supersonic aircraft are thought to damage the stratospheric ozone layer, the protective layer that filters out harmful radiation from the sun.

4. Aviation fuel Jet fuel is a clear to straw-colored fuel, based on either an unleaded kerosene (Jet A-1), or a naphtha-kerosene blend (Jet B). It is similar to diesel fuel, and can be used in either compression ignition engines or turbine engine Aviation fuels consist of blends of over a thousand chemicals, primarily hydrocarbons , additives such as antioxidants and metal deactivators, and impurity. fuel additives are used for any number of applications. Take, for example, those additives used to kill the microbial growth that breeds in the bottoms of fuel tanks , Anti-icing fuel additives are used to prepare the fuel for such a change and keep it from solidifying and adversely affecting engine performance, anti-oxidant and metal deactivator additives to reduce hazardous waste disposal costs associated with cleaning aircraft parts

5. Aircraft Engine Even though aircraft engines are already technologically advanced, high-performing and efficient, engine companies are being challenged to deliver even better products , Reaction engines ( jets , Turbojet , Turbofan , Rocket) . Reciprocating (piston) engines Newer engine types (Wankel engine , Diesel engine , Precooled jet engines , Electric )

6. Major factors Safety: While today’s aircraft have an impressive safety record, any aircraft failure has the potential to be catastrophic, especially if it is engine related Noise: Large airports are sited near major metropolitan centers, and airport neighbors demand decreased noise. At the same time, the number of flights is increasing. Governments have legislated increasingly stringent requirements related to allowable noise levels Efficiency: For many airlines, fuel is now the single largest cost. Price volatility is a major issue. A fuel-efficient aircraft reduces operating costs and increases payload Eco-friendliness: Reduced fuel consumption leads to reduced carbon emissions.

7. Plane Exhaust Kills More People Than Plane Crashes In recent years, airplane crashes have killed about a thousand people annually, whereas plane emissions kill about ten thousand people each year . Airplane exhaust, like car exhaust, contains a variety of air pollutants, including sulfur dioxide and nitrogen oxides. Globally, the team estimated that about 8,000 deaths a year result from pollution from planes at cruising altitude—about 35,000 feet (10,668 meters)—whereas about 2,000 deaths result from pollution emitted during takeoffs and landings. The most common causes of death due to air pollution are cardiovascular and respiratory diseases, including lung cancer, according to the UN's World Health Organization .

8. Clean Sky Reducing emissions from aviation Strategies available to mitigate emissions from aviation include the following Aircraft Efficiency Aircraft efficiency technologies reduce the amount of fuel aircraft use per unit of distance traveled, Several technological improvements exist to improve aircraft aerodynamics Alternative Fuels Alternative fuels have lower emissions that presents a long-term path toward lower carbon Alternative Modes of Transport Switching from aviation to less carbon-intensive modes of transport

9. SOLAR IMPULSE 2, THE SOLAR AIRPLANE Solar Impulse is the only airplane of perpetual endurance, able to fly day and night on solar power, without a drop of fuel This revolutionary single-seater aircraft made of carbon fiber has a 72 meter wingspan (larger than that of the Boeing 747-8I) for a weight of just 2,300 Kg, equivalent to that of a car. The 17,000 solar cells built into the wing supply four electric motors (17.5 CV each) with renewable energy. During the day, the solar cells recharge lithium batteries weighing 633 Kg (2077 lbs.) which allow the aircraft to fly at night and therefore to have virtually unlimited autonomy.

10. Electric Engine About 60 electrically powered aircraft have been designed since the 1960s. Some are used as military drones. In France in late 2007, a conventional light aircraft powered by an 18 kW electric motor using lithium polymer batteries was flown, covering more than 50 kilometers (31 mi), the first electric airplane to receive a certificate of airworthiness .Limited experiments with solar electric propulsion have been performed, notably the manned Solar Challenger and Solar Impulse and the unmanned NASA Pathfinder aircraft.

11. Historic Solar Impulse 2 flight takes off from Abu Dhabi Abu Dhabi: The Solar Impulse 2 took off from Abu Dhabi on Monday morning in an epic adventure marking the start of its five-month journey across the world powered solely by the sun, before it heads back to Abu Dhabi in late July. It will be fully powered by solar energy for the entirety of its trip -- and will not consume a single drop of fossil fuel to keep it in the sky. The aircraft was piloted by André Borschberg, one of the founders of the Solar Impulse 2, for its maiden flight to Muscat, Oman. Betrand Piccard, the co-founder behind the project, will then pilot the aircraft for its second journey, with both pilots alternating for the 12 flights. The Solar Impulse 2 will face tough challenges: Some flights will take as long as five days straight, when it crosses the Pacific towards the United States, for a total of 120 hours of flying time.

12. TOGETHER WE CAN CHANCE OUR WORLD Thank you. http://www.futureisClean.org المهندس : مرزوق جارالله الشريفي