Air travel today is a nightmare of long drives to crowded airports, long queues that move at a snail's pace, and long, boring waits in identical lobbies drinking overpriced coffee. It would be so much easier and less frustrating if catching a plane were like catching a train. If Switzerland’s École Polytechnique Fédérale de Lausanne (EPFL) has its way, its Clip-Air project will one day produce modular aircraft that will allow you to board a plane at a London railway station and disembark in the middle of Rome without ever setting foot in an air terminal.

Under development since 2009, the Clip-Air project aims to merge the speed of air travel with the flexibility of rail transport. Airplanes are specialized vehicles made for particular tasks, so a passenger plane can’t be used as a cargo plane without extensive modification. On the other hand, a train is a collection of modules with a locomotive “module” providing propulsion. Put passenger cars behind a locomotive and you have a passenger train, put goods wagons there and you have a goods train. You can also add specialist cars, such as buffet cars, sleepers, guards vans, tankers, ore carriers, car carriers and many more.

Clip-Air does the same thing with airplanes. Instead of a locomotive, it uses a flying wing containing the engines, cockpit, fuel and landing gear. And instead of cars, there are up to three modules or capsules that are self-contained airplane fuselages. The capsules can be mixed and matched to suit the purpose at hand. A plane can carry all cargo or all passengers, first class or coach capsules, or any combination along with specialized versions. Another benefit of Clip-Air is that the capsules also increase capacity for an aircraft of a given size, with three passenger capsules carrying 450 people, yet the plane can still operate from a conventional airport.

EPFL has designed the capsules so that they are 30 m (98 ft) long and weigh 30 tonnes (29.5 tons). The clever bit about this is that it makes the capsules suitable for rail transport, which provides the potential to alter the design of airports and how they’re used. Instead of going to the airport and boarding planes, passengers could go to railway stations and board capsules as easily as a commuter train, which on reaching the airport would be attached to the flying wing, so passengers never need to go inside a terminal. The same principle applies to industry, with freight loading moved to railway yards or factories.

EPFL claims that this configuration allows for more efficient and flexible fleet management and reduces the likelihood of empty flights. The modular design also provides savings in maintenance, storage and management. In addition, EPFL claims that the design is greener because the Clip-Air can carry as many passengers as three Airbus A320s with only half the engines. It can also be adapted to run on a variety of biofuels or liquid hydrogen thanks to the ability to swap out a regular capsule for the large tanks that hydrogen requires.

Though EPFL is confident about the future of Clip-Air, it admits that the technology has a long way to go before it’s practical.

"We still have to break down several barriers but we do believe that it is worth to work in such a concept, at odds with current aircraft technology and which can have a huge impact on society," says Claudio Leonardi, leader of the Clip-Air project. “The development of the concept requires performing more advanced aerodynamic simulations and testing a six-meters (20 ft) long flying model powered by mini-reactors in order to continue to explore the concept’s flight performance and to demonstrate its overall feasibility.”

A 1.2-m (3.9-ft) model of the Clip-Air plane will be exhibited from June 17 to 19 at the Normandy Aerospace stand at the Paris Air Show. Gizmag will be attending the show and will take a closer look at the concept.

The video below shows an animation of the proposed Clip-Air plane.

Source: EPFL