Two seater fighters are typically used for training and air-to-ground missions. A/G jets usually have some sort of visual targeting system like a targeting pod or sniper which requires it’s own operator which is the responsibility of the WSO. Missions that only require air-to-air support are usually handled by one seater fighters. Missions like intercept and escort. I wish I was at my computer so I could explain this a little better but you get the jist.
Source: had jobs on both styles of jets
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