(FILES) This file photo taken on December 7, 2015 shows an airplane as it flies over Washington, DC, shortly after takeoff from Ronald Reagan Washington National Airport in Arlington, Virginia. Greenhouse gases emitted by commercial airplanes contribute to global warming and endanger public health and the environment, US officials concluded July 25, 2016, opening the path for regulation of passenger planes.The final assessment by the US Environmental Protection Agency supports the goals of President Barack Obama's plan to reduce emissions from large sources of carbon pollution. / AFP PHOTO / SAUL LOEBSAUL LOEB/AFP/Getty Images