The International Air Transport Association ( IATA) last year set itself a long-term, yet ambitious, goal to build a zero emissions aircraft in the next 50 years.

CNN: Flight of biofuel fancy?

According to the International Air Transport Association (IATA) jet engines today are 40 percent more fuel-efficient than those designed in the 1960s, with pollutants such as soot and sulphur now almost completely eliminated from jet exhaust.

CNN: Green wing:?can technology make flying more environmentally friendly?