Environmental Impact of Aviation

Note that the 737/A320 class of plane is by far the most common in the sky and the one that has the largest environmental impact.

Boeing and Airbus have been resisting a clean sheet upgrade of these planes because it would cut into their profits -- even though the impact in terms of lowering costs for airlines, reducing environmental impact, and a better flying experience for the public, would dwarf the 777 and 787 put together.