For most, the idea of a human-powered flying machine with flapping wings like a bird is the stuff of fantasy or the preserve of grainy black-and-white movies of mad inventors jumping off cliffs - and crashing - with their bizarre contraptions.
But graduate students at the University of Toronto have built such an aircraft, called an ornithopter, and flown it successfully during a series of flights believed to be the first in the world for an engineless, birdlike plane.
"It's kind of the original aeronautic dream: Humans looked up at the sky and saw birds and said, 'I want to fly like that,' " said Todd Reichert, a PhD student who led the team that constructed the aircraft.
The plane, dubbed the Snowbird, has a wingspan of 32 metres, similar to a Boeing 737. Mr. Reichert sits in a small cockpit suspended beneath the wings and pumps a bar with his feet to operate a system of wires that pull the wings up and down. To steer, he uses a pair of metal bars attached to rudders on the back of the aircraft.
The plane, made primarily of carbon fibre tubes and covered in a thin polyester skin, weighs less than 100 pounds (45 kilograms). To keep the aircraft's total weight down, Mr. Reichert had to shed nearly 20 pounds.
Like many large birds, the craft requires a running start to get airborne. To achieve this, it is towed behind a Smart car, then released to fly on its own.
On Aug. 2, Mr. Reichert kept it at an altitude of a few metres for 19 seconds, covering 145 metres at 25.6 kilometres an hour on the grounds of a flying club near Tottenham, Ont.
While the distance and speed may not seem like much, they are a big aeronautical first, he said. An official from the International Aeronautical Federation observed the flight, and the university expects the organization to certify it as the world's first successful human-powered ornithopter flight.
Mr. Reichert became interested in the idea four years ago and approached James DeLaurier, a U of T professor who has built engine-powered ornithopters in the past. (An ornithopter is an aircraft that flies by moving its wings up and down like a bird, unlike conventional airplanes, which use fixed wings.)
First, the student created computer simulations using Leonardo da Vinci's famous 1485 sketches of such a machine as a starting point. Then, in a farmer's barn near Tottenham, he and more than 20 fellow students assembled the plane.
In September and October of last year, they held test flights, crashing several times. After design improvements, the plane flew this past summer.
Prof. DeLaurier attributed the project's success - compared to the many who have tried and failed - to modern materials, sophisticated computer programs and advancements in the understanding of aerodynamics.
"When you try to tell someone what you're working on, they kind of back away slowly," he said. "But when you see it fly, it takes your breath away."
The machine will likely be donated to a museum. While the team's findings in the field of avian ergonomics will inform other researchers, the plane's primary purpose was the sheer desire to make aviation history. In fact, Mr. Reichert's PhD thesis will consist purely of the theory behind the Snowbird - actually building it was just a thrill.
"When you're in [the cockpit] you're so focused," he said. "Once you finally relax and land, it hits you. Maintaining your height under your own power is so cool."
Ornithopters through the ages
Early 1000s - According to medieval history books, a young monk named Eilmer tried to fly in the western English village of Malmesbury by attaching a pair of cloth wings to his arms and jumping off the top of the local abbey. He is reputed to have sailed about 200 metres through the air and crashed on a local street, breaking both his legs. He survived the mishap, however, and is thought to have lived to a ripe old age, being one of the first to spot Halley's comet in 1066.
1480s and '90s - Leonardo da Vinci, the great Italian Renaissance artist, sketched designs for various flying machines in his notebooks. In one, the pilot lay on his stomach on wooden boards and used stirrups and hand cranks, attached to pulleys, to move the wings up and down. In another design, a harness attached to the pilot's head operated a rudder to steer the contraption. It's not clear whether Leonardo ever attempted to build and fly an ornithopter himself, but his designs provided inspiration for Todd Reichert and his team.
1870 - Frenchman Gustave Trouve, who would go on to design an electric car, built an unmanned ornithopter powered by a crude internal combustion engine fuelled with gunpowder. His explosive invention flew for 70 metres on one occasion and is believed to be the first flapping-wing aircraft to fly.
1890s - Otto Lillienthal created a series of gliders with fabric stretched taught over a willow frame and flew them by jumping off hilltops and buildings. Two of these were considered ornithopters, with small engines that propelled the wings up and down. Although he was able to fly with the contraptions, it is generally believed that he was gliding with them rather than flying under the machines' own power. He died after crashing one of his contraptions in 1896.
1929 - Another German man, Alexander Lippisch, designed a human-powered ornithopter flown by his students and towed into the air. A foot pump activated cables that flapped the wings. The pilot sat at the front of the fuselage, in a seat open to the air. The machine successfully flew more than 200 metres. While Mr. Lippisch maintained it flew under the pilot's power, others say it was merely gliding.
1940s - Adalbard Schmid built and flew a motorized aircraft with both fixed wings and a pair of flapping wings behind it. With a fuselage resembling a large sausage, it was able to stay in the air for 15 minutes at a time.
2006 - James DeLaurier and a group of students designed and flew an engine-powered ornithopter. The craft had a 24-horsepower engine, helped by a small turbo booster. It flew for 14 seconds at speeds of more than 88 kilometres per hour. The plane crash landed, damaging the nose.