Anyone looking to book a flight this summer can see why greener, more fuel-efficient aeroplanes will be a good thing: soaring fuel prices have had a stratospheric effect on ticket prices. Add in the carbon costs to the climate, the growing number of air travellers and the frightening trend of cracked fuselages — and a new fleet of eco-jets sounds rather timely.

While aeronautic design has come far since the advent of the passenger jet plane, making them lighter and more efficient, many designers feel that we've gone about as far as we can go with cigar-shaped fuselages and under-wing engines. Researchers at MIT, led by Dr Mark Drela and tasked by NASA, have come up with a double-wide design: instead of the traditional single cylindrical body, two partial cylinders are joined together with three engines at the back of the plane between the double tail. This D-series is more fuel-efficient, with longer and thinner wings that reduce drag and the amount of fuel burned; the D8.5, which would be constructed from composite materials available by 2035, would burn 70% less fuel and release 75% less nitrous oxide. Although the plane would be marginally slower than a 737, the wider fuselage would allow for an extra aisle, meaning faster boarding and deplaning, for a quicker journey overall.

The MIT team also developed an H series to replace the 777 for international flights. The design, a more radical triangular wing-body shape, combines the plane's fuselage with the wings and has no tail.

Meanwhile at Imperial College in London, Varnavas Serhides designed a plane that has no tail by taking advantage of advanced "fly-by-wire" controls and eliminating the need for a horizontal stabilizer and vertical tail, which also reduces drag. Another designer has ideas to create "smart wings" with materials that change shape or have holes that can be open and closed to create the kind of airflow needed to maintain or reduce air speed.

With 3.3 billion flights expected to be made by individual travellers in 2014 and the growing challenge of climate change, green aeroplanes can't take off soon enough.