Human-powered flight is about as green as it gets, although the pilot/powerplant does emit CO2 and some methane during the exercise. A human pilot can put out only about 0.25 to 0.5 horsepower for reasonable periods, with the record holders like Brian Allen flying The 70-lb Gossamer Albatross in its 26-mile cross-channel flight in 2 hours, 49 minutes,.and Olympic cyclist Kanellos Kanellopoulos of Greece flying 71.5 miles between Crete and Santorini in 3 hours, 54 minutes on April 23, 1988. The flight holds the official FAI world records for total distance, straight-line distance, and duration for human-powered aircraft. The British Human Powered Flying Club holds a gathering of the hopeful every year, this year at Lasham Airfield, between London and Winchester. Depending on how one looks at it, only six competitors showed up this year – or amazingly, six competitors who had designed, built, and test flown their craft, showed up this year. Building even a simple airplane is a relatively complex task: dealing with …