On Sat, 02 Jun 2007 13:06:12 -0400, "Stephen J. Rush"
wrote:

On Sat, 02 Jun 2007 07:46:33 -0700, John Larkin wrote:

On Sat, 2 Jun 2007 17:27:03 +1000, "Phil Allison"
wrote:


"Tom Del Rosso"


Hey, what about the effect of chaff on these things?


** The main targets for allied AA shells with VT fuses were German V1 flying
bombs, Japanese Kamikazes and attacking torpedo bombers.

Prox fuzes in artillery were very effective late in the European war;
Patton gave them a lot of credit for speeding him into Germany, and
the prox fuze was instrumental in stopping The Bulge. Regular
artillery would tend to bury itself in the ground, and foxholes were a
useful defense. Prox shells could be set to detonate 30 feet above the
ground, spraying shrapnel downward. It was devastating to troops. I
have a photo in one of my books of a test, with wooden boards
representing soldiers, with every board within 30 meters penetrated or
shredded.

The prox shells was used against land forces only late in the war when
it was felt that the Germans were going to lose and didn't have time
to copy them.

You don't really need a proximity fuze in surface-to-surface artillery. A
mechanical time fuze, like the first AA fuzes, can be set to fire a few
yards above the ground if you know the elevation of the target. Both
sides used this "time fire."

The "few yards" thing doesn't compute.

Effectiveness against ground forces peaks rather sharply at a burst
height of just about 10 meters. If a shell is traveling a couple of
hundred meters per second, critical timing accuracy will be in the
milliseconds, out of seconds of flight. That just can't be done with
fixed timers, especially given changes in propellant charge, wind, and
elevation. In the Battle of the Bulge and later action, after the prox
fuses were released for land use in Europe, 10-meter high bursts were
being achieved at ranges of 15 miles, day and night. See Baldwin, pp
280-281.


John