Ack-Ack
My apologies, seems he did want it enabled for Online. To that I say:
-1000
No way! I like this game because they make a good balance of Realism and immersion. Enabling your idea would destroy that immersion. Why not add In Flight Pick Ups as well, or enable F3 mode for all planes because that way you can 'see what killed you'.
Make it an option in the Filmview as it would make it a valuable learning tool, especially for those who fly new planes occasionally.