Damaged by flak ?

[Jemiba]

Me and my family watched a docu about WWII recently (was kind of homework for my son ..).
Amongst all other stuff, quite a lot of footage of AA-guns defending Britain/Germany and the US
fleet in the Pacific was shown, besides heavy guns the light ones with 20 to 40 mm. And then came
the question from my daughter: If such a shell doesn’t hit anything, what happens then? Well, it comes
down to earth again. And then ? Hm, larger calibers were time fuzed, so only splinters came down, but
the smaller ones should still have been intact, when reaching the ground. I’ve tried to google, but it
seems, it isn’t that easy. For most keywords I’ve tried, I just got hits for sites about wargames and so on.
In fact, German and British cities must have suffered a hail from their own small caliber AA shells. And during
the last parts of the film, footage of US warships was shown, firing fiercely against Kamikazes, while in the
same line several destroyers/cruisers were visible. There, too, must have been self-inflicted damage/casualties
regularly. Anybody knows of statistics or reports ?
Maybe it wasn’t regarded as important, but to my opinion it must have been a considerable danger.

 

[Lauge]

In WW II, ammunition all the way down to 20mm in calibre could be/were equipped with self destruct (not sure about the smaller stuff, like the German 13x64mmB). This was either a function of the fuze or the tracer, and would detonate the explosive fill after a certain period of time. Attached is an image of a German 20mm HE shell with self destruct via tracer burn-through ("zerlegeeinrichtung" in the drawing).

Shells without self destruct were also available, but these were mostly for use against ground targets (e.g. defending the anti-aircraft gun emplacement against ground assault).

But of course, if you fire at an airborne target using non-explosive projectiles (regardless of calibre), whatever doesn't make a solid hit will come back down.

Regards & all,

Thomas L. Nielsen
Luxembourg

 

[Jemiba]

Ah, thanks for this explanation. A friend of mine once showed me a (current)
20mm shell he still had as a souvenir, disassembled, and IIRC there was nothing
like a self-destruct device,but as he was tank driver, this shell probably was for
ground use only.

 

[Lauge]

Well, the "visibility" of the self destruct would depend on how disassembled the shell is. A self-destruct device integral to the fuze, for example, might not be readily apparent, unless the fuze itself is also disassembled.

How such a self-destruct fuze can be made is illustrated at:
http://www.xs4all.nl/~robdebie/me163/weapons15.htm#Type I
(scroll down to "ZZ 1589 B fuse").

Regards & all,

Thomas L. Nielsen
Luxembourg