Twice.
First time was in a Mustang D chasing down a bomber (I think it was a Lancaster) in version 1.09. I was still figuring out how to toggle weapons and had inadvertently left my secondary weapon to be rockets instead of all guns. I got so close that I popped the Lancaster in the tail with a rocket.
Second time was more intentional. I had taken a heavy Mustang to hit an enemy airfield and had just bombed the vehicle hangar. I was crossing over the airfield to rocket the town when a Bf109 spawned on the runway along my flight path. As he was lifting up, he brought his nose to bear on me so I turned head-on towards him and fired three rockets (rate of closure was so quick I knew I couldn't get him with just two .50 cals). He took a rocket to the nose. as the rockets took out the 109, my guns pinged up the N1K2 spawning behind him. Unfortunately, the N1K2 happened to be sitting on the runway at just the right pitch angle and took me out as I passed by.