Since the early days of jet aircraft, aviation has dramatically improved its environmental performance. Since the 1960s, fuel efficiency has improved by some 70% per passenger km, today’s aircraft are 75% quieter than those manufactured 50 years ago, and levels of carbon monoxide have come down by 50% and unburned hydrocarbons and smoke by around 90%.
The airline industry has played an instrumental role in advancing technical certification for biofuels which can now be used on passenger flights. The first commercial flights using biofuels were achieved in 2011.
Governmental support is essential to achieve the industry's climate goals from sustainable alternative aviation fuels. See IATA's Sustainable Alternative Aviation Fuels Strategy (pdf)