The issue with the exploding but still flying planes have been eyewitnessed several times, mostly on the Repka server due to the high density of the dogfights.
I also find it much more promising to attack a target not from 6 o´clock level but high or low, especially bombers sicne you can hit in that way the pilot or the fuel tanks better. However the problem remains, that you can´t chose your firing angle often, especially when a 109 tries to escape in a dive. In a dogfight it is a good idea to attack someone while he/she is turning sicne your bullets will have a lots of surface to impact on
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