May 1, 2008 Those magnificent men in their flying machines. This European summer, Frenchman Stephane Rousson will attempt to cycle across the English Channel, pedalling a twin-tilting-rotor helium airship. It's the first pedal-powered airship of its kind, complete with very delicate aerodynamics that mean Rousson will need to chance upon one of the three windless days of the year if he hopes to stay up-diddly-up-up and not go crashing down-diddly-own-down.

The English Channel, its narrowest point only a tantalizing 21 miles wide, has for centuries inspired ingenious and often ill-fated inventors to try their luck at crossing in a variety of contraptions - usually more for glory than practicality. The first air crossing was more than 300 years ago, as balloonist Jean-Pierre Blanchard floated from Dover to Calais. 90 years later, in 1875, Matthew Webb became the first swimmer to make it from one side to the other. The first aircraft heavier than air to cross the channel made it over in 1909, and the first hovercraft in 1959.

The first purely human-powered aircraft, the Gossamer Albatross, crossed the channel in 1979, its pilot Bryan Allen pedaling the feather-light winged plane across in two hours to collect the UKP100,000 Kremer prize, and it was this attempt that caught the imagination of French cyclist Stephane Rousson.

"Crossing the English Channel with a pedal-powered airship is both totally unnecessary and a very eloquent statement on human nature" says Rousson's website. His craft, Zeppy, is a helium-filled balloon airship that's just heavier than air. The pilot pedal-powers two propellers that operate on a tilting axis; take-off is achieved with the propellers in a horizontal alignment like small helicopters, and the pilot can then rotate them forward to produce forward thrust in the same was as this is achieved in a tilt-rotor aircraft, or move the propellers independently to achieve steering.

Zeppy, which Rousson believes is the world's first pedal-powered airship, was originally designed and built by Luc Geiser and his father Jean-Marc, but the duo never managed to make it fly. Rousson acquired Zeppy from the pair and made repairs and upgrades to get it in the air - but Jean-Marc died just a few days before Zeppy made its maiden flight.

The delicate nature of Zeppy's aerodynamics means that conditions will have to be just about perfect for Rousson to mount his Channel crossing attempt. Winds of as little as 10km/h pose a genuine threat that Rousson will end up wet and sorry instead of triumphant - and seeing as perfect, windless days happen about three times a year across the channel, the attempt will be as much about waiting and hoping as it is about pedaling.

Rousson hopes he'll find the right window of weather sometime this June. Our best wishes go with him, good luck sir!

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