Similarly, public transportation buses are built from recycled iron and steel. Recycled steel allows, for example, an old car to be recycled into vital material used to fabricate the frame and paneling of a new bus. Using recycled steel saves energy,
conserves natural resources, and reduces CO2 emissions by up to 58%. More than 14 million tons of steel is recycled from autos each year.
In a similar fashion, approximately 40 to 50% of the weight of an end-of-life aircraft is returned to the parts distribution pipeline,
as overseen by the U.S. Federal Aviation Administration and European Aviation Safety Agency.
In addition, 85-90% of the weight of a retired airplane is re-used or recycled. In some cases, excess carbon fiber from airplane manufacturing is also being used as recycled carbon fiber in other products such as automobiles.
Researchers also recently published findings on the potential to improve the structural safety of buses without adding weight by incorporating recycled
materials from the aircraft industry.