I'd say fake.
1. The plane in the background has the "laserbeam" tracers
2. The plane also has some weird looking effect from behind like a wake someone tried to put into the photo for "coolness"
3. the plane diving away if you lok closely you can see a black line from the film like what many had back in the day, the wing of the plane seems to be on TOP of the line, hence photoshoped in.
It would appear this photo is a still taken from a film, the planes were photoshoped in.
I've seen alot of old B/W WWII photos digitized and tho I'm no expert in any sense of the word it has the feel of fake and with the inconsistencies with the LW planes it doesnt seem authentic.
The second fighter really is the deal breaker for me. It's not even the tracers really its that odd shading behind the fighter, like someone was trying to give it the appearence of "swooping" in for the kill.
Sorry, it would have been a really awesome find if it was real. Still it looks cool tho