The shape of aircraft to come

Driven by the need to reduce fuel costs and defuse political pressure, the aviation industry is pouring millions of pounds into developing greener planes. The most striking prototype is the "blended wing" jet, where the plane is built as a giant wing and burns a quarter less fuel than a conventional aircraft. It also has improved aerodynamics. The blended wing is in development by various organisations, including Boeing, which flew a 21ft prototype last year. However, Boeing has ruled out a passenger version until 2030.
Rolls-Royce is testing a prototype based on fuel-cell technology which combines hydrogen and oxygen to produce electricity. However, it is impractical for passenger aircraft because a fuel cell takes up to 50 times more space than a conventional engine.
The government-backed Omega programme is working on a "pulse-detonation" engine which powers the aircraft by a series of controlled, rapid explosions and uses less fuel. There is one drawback: it sounds very similar to machine-gun fire. EasyJet has attempted to push aircraft manufacturers into starting work on green plane prototypes sooner by cobbling together existing technologies to produce a mock-up of an "ecojet" last year. Its most distinctive feature is "open rotor" engines, which again use less fuel than conventional motors. However, open rotor engines have been ignored by airlines because they are noisier. For now, easyJet's design is limited to a plastic model displayed before the press.

The Guardian
Dan Milmo
February 25 2008