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aminx
06-20-2004, 08:27 AM
i read that the shell used by this antiaircraft canon introduced after pearl harbour could feel
the presence of metal close by before exploding.
can someone explain how does this work?
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg

aminx
06-20-2004, 08:27 AM
i read that the shell used by this antiaircraft canon introduced after pearl harbour could feel
the presence of metal close by before exploding.
can someone explain how does this work?
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg

Zyzbot
06-20-2004, 08:41 AM
Are you referring to a proximity fuse?

if so...see this link:

http://www.history.navy.mil/faqs/faq96-1.htm

Fliger747
06-20-2004, 11:29 AM
The "proximity fuse" for the 5" 38 cal Dual Purpose weapon utilized a simplified "radar" to trigger the fuse when approaching within 70' of the target. This greatly increased the effectiveness of what was the finest Naval AAA weapon of the war (coupled with the Mk 37 director system). Without the VT (variable time) fuse I expect that the Great Blue Fleet would have had even a tougher time slogging across the Pacific.

aminx
06-20-2004, 02:00 PM
thanks for detailed info.i never realised a shell could be so complex and rugged.
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg

Bull_dog_
06-20-2004, 02:15 PM
Is it Fuze or Fuse...

CPS_Shadow
06-20-2004, 03:10 PM
Variant spelling

fuze

noun, transitive verb

See: fuse[2]

Blutarski2004
06-21-2004, 09:28 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by aminx:
thanks for detailed info.i never realised a shell could be so complex and rugged.
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg <HR></BLOCKQUOTE>


..... Good book on the subject, THE DEADLY FUZE, by Ralph Baldwin. Go here -

http://www.jhu.edu/~gazette/julsep95/aug2195/21apl.html

for an interesting overview as well. This very same VT fuze was also used by field artillery in both Europe and the Pacific to produce reliable airbursts which were very deadly against infantry.

BLUTARSKI

aminx
06-21-2004, 12:06 PM
thanks blutarski for info,
actually my curiousity was triggered while reading "fire in the sky" which i just completed.i just could'nt get round figering how it worked,but then i am not an engineer nor have i studied any form of electronics.i am trying to educate myself as much as possible on the pacific war while waitting for the sim.
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg

Gibbage1
06-21-2004, 12:18 PM
The VT fuse was AMAZINGLY simple in reality. It was a small radio that sent out a radio signal in flight. When it recieved its own siglan (bounced back from eather an aircraft or ground like Radar) it exploded. They were amazingly accurate and saved many ships in the Pacific. The first field test of VT fuse was against 3 betty bombers. 3 shells were shot, 2 betty bombers were distroyed. Thats astonishing accuracy considering hundreds of shells would have been expended to do the same with standard timed fuses.

The VT fuse also served in England against Buzz bombs. This fact is quickly glossed over, but once the US set up VT fuse positions along the coast, the accounted for 80% of the incomming buzbombs. I myself had never known that till later when I did some research on the VT.

Also they were used in Europ on the ground to GREAT effect against entrenched German troops. Since the shell would go off at a set altutude above the ground it would rain shrapnal down into the trenches.

"Most P-39's were sent to the Russians - so I guess that was an American secret weapon against our Russian allies."

Stan Wood, P-38 pilot who also flew the P-39.

Blutarski2004
06-21-2004, 03:37 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by aminx:
thanks blutarski for info,
actually my curiousity was triggered while reading "fire in the sky" which i just completed.i just could'nt get round figering how it worked,but then i am not an engineer nor have i studied any form of electronics.i am trying to educate myself as much as possible on the pacific war while waitting for the sim.
aminx

http://img25.photobucket.com/albums/v76/aminx/113.jpg <HR></BLOCKQUOTE>


..... It's really a remarkable engineering story as well as war story. In the course of about one year, engineers developed a miniature self-powered radar transmitter/receiver, small enough to stuff into the nose of a 5-inch projectile, and tough enough to withstand something like 70 G's acceleration. Nothing like it had ever been attempted before.

It was judged that this fuze tripled the effectiveness of the 5/38 DP projectile in the AA role. Due to production shortages and huge demand, ships rarely if ever carried all VT in their magazines. IIRC, it was usually something like a 1/3VT and 2/3 mechanical fuze mix.

Another good discussion of the VT fuze can be founf in the book U S NAVAL WEAPONS, by Norman Friedman. Well recommended.

BLUTARSKI