Aviation

Aviation is the practical aspect or art of aeronautics, being the design, development, production, operation and use of aircraft, especially heavier-than-air aircraft. The word "aviation" was coined by French writer and former naval officer Gabriel La Landelle in 1873, from the verb "avier" (synonymous flying), itself derived from the Latin word "avis" ("bird") and the suffix "-ation".
==Environmental impact==
Like all activities involving combustion, operating powered aircraft (from airliners to hot air balloons) release soot and other pollutants into the atmosphere. Greenhouse gases such as carbon dioxide () are also produced. In addition, there are environmental impacts specific to aviation:
*Aircraft operating at high altitudes near the tropopause (mainly large jet airliners) emit aerosols and leave contrails, both of which can increase cirrus cloud formation — cloud cover may have increased by up to 0.2% since the birth of aviation.Aviation and the Global Atmosphere (IPCC)
*Aircraft operating at high altitudes near the tropopause can also release chemicals that interact with greenhouse gases at those altitudes, particularly nitrogen compounds, which interact with ozone, increasing ozone concentrations.
*Most light piston aircraft burn avgas, which contains tetraethyllead (TEL). Some lower-compression piston engines can operate on unleaded mogas, and turbine engines and diesel engines — neither of which requires lead — are appearing on some newer light aircraft.
==See also==
*Aeronautics
*Aviation, aerospace, and aeronautical terms
*Environmental impact of aviation
*List of aviation topics
*Timeline of aviation
==Notes==
==External links==
*
*
*
*
*
Category:Air Pollution