First dirigible. Henri Giffard, a French engineer, flew in a controllable (more or less) steam-engine-powered balloon, 144 ft long and 39 ft in diameter, inflated with 88,000 cu ft of coal gas. It reached 6.7 mph on a flight from Paris to Trappe (Sept. 24).

Henri Giffard, a French engineer and inventor, who built and flew the first full-size airship. His cigar-shaped, nonrigid bag had a capacity of 113,000 cubic feet (3,200 cubic meters) and was 44 meters (143 feet) long. Its 3-horsepower (2.2-kilowatt)-steam engine drove its propeller, and it had a rudimentary vertical rudder. The gondola was suspended from a pole that hung from a net surrounding the balloon. The engine weighed 250 pounds (113 kilograms), and the airship also had to carry a 100-pound (45.4 kilograms) boiler and the coke required to fire it.

Giffard's first flight took place on September 24, 1852. He traveled almost 17 miles (27 kilometers) from the Paris racecourse to Trappes moving approximately 6 miles per hour (10 kilometers/hour). However, Giffard's airship could be steered only in calm or nearly calm weather. With any more wind, the airship could fly only in slow circles. A lightweight engine powerful enough to overcome more than light breezes had not yet been invented. Using current technology, an engine with enough power to operate an airship in windy conditions would have been prohibitively heavy. Not until the development of light, efficient internal combustion engines at the end of the nineteenth century would airships become practical.

Realizing that the engine was too heavy for his balloon, on his next flight Giffard suspended it beneath a second, large bag of 113,000 cubic feet (3,200 cubic meters) capacity. On a trial trip, gas escaped and the balloon became misshapen. The nose tilted up and some of the lines that held the car in place broke. The balloon escaped from the net and burst. Surprisingly, Giffard and his passenger were only slightly injured.

For Giffard's third and final attempt, he planned an even larger balloon&emdash;1,970 feet (600 meters) long, 98 feet (30 meters) in diameter at the middle, and with a capacity of 7,800,000 cubic feet (220,871 cubic meters). He designed a steam engine that weighed 30 tons (27,216 kilograms) which he thought would move the ship at 45 miles per hour (72.4 kilometers per hour) in still air. However, because of its cost, this huge airship was never built.