International flight 1785, when Jean-Pierre Blanchard and John Jeffries crossed the English Channel in a hot air balloon. It took more than a century for the first heavier-than-air object to repeat this process: Louis Blériot crossed the English Channel on July 25, 1909, winning a "Daily Mail" prize of £1,000. Aviation technology developed during World War I, with aviation between the World Wars seeing the development of international commercial flights. There was a combination of aircraft types which included airships and airplanes. The first airline to operate international flights was Chalk's Ocean Airways, established 1917, which operated scheduled seaplane services from Florida
Tradeoffs for locomotion in air and water balloons. By changing the amount of gas in these swim bladders, fish actively control their density. If they increase the amount of air in their swim bladder, their overall density will become less than the surrounding water, and increased upward buoyancy pressures will cause the fish to rise until they reach a depth at which they are again at equilibrium with the surrounding water. In this way, fish behave essentially as a hot air balloon does in air. Some seabird species utilize surface feeding or plunge diving during foraging in which gravity and/or momentum is used to counteract buoyancy effects