Rip, that flash is a hit sprite from being hit by one of the bombers guns.
One of the graphical features (only thing in this update as I understand) I like in this beta WBIII is the appearance of the ground down low. It dissolves into a somewhat higher resolution, than what it appears from altitude.
It's a bit hard to explain, but noticeable when looking for it.
Since AH has alot of actions going on at/by the ground this feature is something that should be looked into implementing into AH. From screenshots I have seen this is also present in IL-2.
[This message has been edited by LLv34_Snefens (edited 03-15-2001).]