Two years after the first manned flight, the Wrights mastered control sufficiently to fly the first circle – a major aviation advance that went almost unnoticed. By World War II, the first hydraulically boosted controls were invented, enabling pilots to fly aircraft weighing more than 100,000 pounds without the muscles of a co pilot. Once digital signals succeeded in maneuvering spacecraft, computerized fly-by-wire technology for aircraft was not far behind.