Since the Il-2 has the "bomber" mode removed, it's the only pure "attack" plane in game. But if you set the "Attack Planes" filter on the clipboard plane list in hangar it doesn't appear there anymore.
(Another thing coming to my mind ... the primary label of a plane does decide to which category any won perk points are going to. A fighter/attacker will always get fighter perks, a bomber/attacker will always earn bomber perks. But a pure attack plane?
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