Rear-mounted "open-rotor" engines offer unrivalled environmental performance for short-haul flying due to their higher propulsive efficiency. However, the significant difficulties in fixing such a large engine beneath the wing of a narrow-body aircraft, make rear-mounting of the engines the best solution.

A lower design cruise speed to reduce drag and a shorter design range to reduce weight. Will someone please tell Mr Harrison to duck, because there's another plane heading straight for his ear.

Noise reductions are expected to come from a gear box between the engine and the open-rotor blades keeping them subsonic during take-off and landing, the use of the rear empennage to shield the ground from engine noise, and airframe improvements (such as no slats on the front of the wing).

The airframe will be made of advanced weight-reducing materials similar to those used in current projects like the Boeing 787, which itself is estimated to be 27% more fuel efficient than the aircraft it will replace in many fleets.

Nothing about improving their rotten food, though, which without a doubt increases EasyJet passengers' gas emissions. [EasyJet press release and O'Reilly-GMT]