A dedicated, well armored single-engined attack plane - would it be of use for the RAF, USAAF and/or other 'Western Allied' air forces? A plane entering the service in, say, mid 1941, either a 'classic' layout or a pusher. It need to be able to carry plenty of armament (guns/cannons, bombs/rockets), perhaps able to dive bomb. The speed, even in 'clean' configuration, is in 300 mph range, maybe up to 350 in war's ending -we can discuss the pros cons of such a plane for years after 1941, too.