Other trends include the ability of planes like the F-35 to carry more bombs, but smaller, lighter bombs, which allow planes to fly further and hit more targets. The entire military is also pushing defense companies to build products that can operate on a single software platform.
O'Bryan said the air defense system of the future will include fewer single-mission aircraft—planes that really only have one job—in favor of aircraft with multiple roles. "Ninety percent of every aircraft's lifetime is peacetime, and it also has to contribute in that time as well, whether it be intelligence-gathering or surveillance."
It's a big shift from when he started flying F-18s a quarter century ago.
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"When I flew, it was 'speed is life,'" said O'Bryan. "In today's fifth generation (aircraft), it's 'information is life.'"
He said the old days of aerial dogfighting are over. If an F-35 pilot is ever actually seen by an enemy, he or she has done something wrong. There's no need to ever get that close.
"It's probably less romantic," O'Bryan said, "but I never met a fighter pilot who wanted a fair fight."
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Correction: An earlier version of this story incorrectly stated that the F-35 is the only active fighter line in production in the United States. In fact, Boeing still produces F/A-18s and F-15 fighters in St. Louis, Missouri.