Thanks for posting this. I heard a story like this from my eighth-grade science teacher and until now I’ve never known whether I should believe it. Mr. W. was a great one for telling urban legends. He was entertaining as hell but less than perfectly reliable.
Years ago I read an account that claimed Francis S. “Gabby” Gabreski, famed WWII Thunderbolt ace, said he shot himself down. He was strafing a runway and the tracer stream suddenly hit a defecting surface at the correct angle to bounce back up into his engine. He pulled up, lost power, and made an emergency landing in German-occupied France. Supposedly this book was quoting him.
But I just went to double-check that tale, and Wikipedia claims he hit the runway with his prop tips. Another page I found said he hit a small rise with his prop tips. I cannot currently tell if that means my source was unreliable, my memory is unreliable, or the well-known tendency of biographers to gloss over the mistakes of their heroes means the internet sources are glossing over the shootdown as an embarrassment. The fact that some sources add wording about “a rise” leads me to suspect excuse-making, but I will have to do more research, I guess.
My father was a bomber pilot in World War II. Gunners are supposed to fire their weapons in short bursts. On one occasion, he was flying a training mission with some very green recruits. One of them held down the trigger for much too long. The gun barrel melted. A bullet went awry, and blew a two-foot hole in one of the tailfins.
Dad flew 50 combat missions, and never lost a plane or a man. Then he nearly got shot down by his own crewman.
“He was strafing a runway and the tracer stream suddenly hit a defecting surface at the correct angle to bounce back up into his engine.”
Sounds awfully dubious. Unless you recovered the bullet and checked it, all you’d know is your plane got shot. And the idea that a ‘stream’ was deflecting back sounds awfully unlikely based on what I know about ricochets.
I suspect more likely it was somehow turned into that story rather than something being ‘covered up’ as it would be a one in a million rather than a ‘silly mistake’ if it did happen.
Otara
I want to be clear about this.
Every single poster in this thread has been astonishing.
Wow.
You are fantastic 
I heard that Max Immelmann, one of the first WWI aces, was killed when he shot his own propellor off after his synchroniser gear failed. Reading his wiki article, it seems this is in dispute, but it does say this happened to him on two previous occasion, although he was able to crash-land each time.
There’s also this sad story about a CH-47A helicopter that shot itself down.
I’ve heard a story about A-10 Warthogs and the Gatling Gun they can carry. When firing depleted uranium slugs, the recoil could be sufficient to stall the airplane. Anything to this?
The original invention of a propeller that could be shot to pieces by the airplane’s own guns was a prime example of “built-in obsolescence”.
It’s very likely that most of these incidents would never have been reported because it is unlikely anyone witnessed it or that anyone would have lived to report it.
Wiki suggests that it might be possible, but unlikely:
A flameout could definitely lead to a stall in the right (wrong?) conditions, as could ordinary recoil if the plane was already close to stalling. Imagine a shallow dive ending with a burst of cannon fire and a sudden climb – if the pilot was already close to stall speed, the cannon’s recoil could slow them down just that extra bit, especially if combined with an engine flameout.
I thought I was going to be purely a spectator in this thread till this jolted my memory of seeing a film clip of a bouncing bomb test going wrong…
And here’s the (melancholy :() film of it…