One possibility that has appeared in discussions of the sixth-generation fighter is that it might be unmanned. The advantages of such an approach are obvious. Eliminating the pilot means being able to do away with the space and weight needed for human accommodation, while the aircraft's performance would no longer be constrained by human endurance. Additionally, this eliminates the risk of human losses in aerial operations. That at least some of the next generation of fighters might be remotely piloted seems plausible enough, given the increased use of such aircraft in reconnaissance and strike missions.
More radical, however, is the question of aircraft which are fully autonomous. Doing away with remote control would reduce the reliance on a vulnerable communications link, on the inevitable time-delay and disruptions to the data transfer between the aircraft and a distant operator, and human reflexes. Additionally, a fully autonomous aircraft would greatly simplify the trouble and expense of training operators.
However, this mode of operation is far less common at this point, requiring as it does more advanced artificial intelligence than anything available. Yet, those who are bullish on this issue speculate that human-grade artificial intelligence might be available by the 2020s, just in time to be an option for the designers of the first crop of sixth-generation fighters. And of course, assuming continued progress on AI past that point, better-than-human artificial intelligence would set the standard, pushing human beings out of the cockpit once and for all.
Still, even if the optimists are right about this trajectory, it is unlikely to come about all at once. We might see intermediate steps, such as smarter aircraft systems, like the "intelligent flight control system" currently under study in some research programs, and sufficient automation to enable designers of strike aircraft like the F-15E Strike Eagle and F-18F Super Hornet to dispense with Weapons Systems Officers. This is not the limit of present ambition, however; Russian publicists for the PAK-FA promise the aircraft will have an expert system with near-human capability. And capability which is merely "near-human" might still be seen as adequate for an autonomous aircraft because of the other advantages it offers.
For the moment, though, a very large question mark hangs over this issue.
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