Cannonball got it correct in one, on the original post. John (Not The Armorer), Old Fat Sailor, Neffi, and Heath were all pretty close, too.
See it in all its readable glory by clicking here.
It is a mechanical meteorological ballistic corrections computer. Something we Americans did manually, with the Met Data Correction Sheet, and, of course, now do via computer. Basic data for artillery is computed off of a set of "standard conditions" to provide a basis against which to measure deviations from standard, to account for the variations that occur in the real world.
To improve accuracy, you measure the conditions in the region between the guns and most likely targets, and using various tools, tables, etc, you calculate the deviations from standard conditions, and from that determine corrections that you apply to the basic data that account for the non-standard conditions, thus enhancing your accuracy.
You can do the same thing by "registering" the guns - but that requires shooting the guns. You pick a point, shoot standard data for it, correct your fall of shot until you hit the target and then measure the difference between the "should hit" (standard conditions data) and the "did hit" (all the messiness of the real world) to determine your corrections. Of course, those are only good for a narrow arc along the line of fire, as the impact of wind and rotation of the earth, for example, differ along different azimuths of fire. Plus, even if you have an enemy conveniently handy to use as a registration point there are some drawbacks to this method . Among those problems are giving away the position of the guns, getting clearance to shoot where you need to register (troublesome when you are fighting a war like the one we currently find ourselves in, i.e., a 360-degree one full of non-combatants), and the fact that you have to do it every time the conditions change much. Which means whenever a weather front comes through, or the sun comes up or goes down. When you register you are also shooting rounds that otherwise might be more usefully employed against the enemy, and, if you are registering on the enemy, well, he might get annoyed and shoot back, too.
So, artillerists came up with other ways to do things. This particular version is Swiss, for their license-built Swedish Bofors 105mm L42 gun. And in the current setup, for Charge One of the pointed HE round. That would be vice charge 2... or a different projectile, such as illumination, smoke, etc.
That dial in the upper right hand side is the heart of the device. You set off the wind direction and speed on that dial (in relation to the muzzle of the gun) and the linkages there transmit the requisite changes to the other rules, thus allowing you to gather your entry arguments and now determine your corrections to apply to the data.
More, excruciating detail is available here at Global Security...
Well done, guys.
See it in all its readable glory by clicking here.
It is a mechanical meteorological ballistic corrections computer. Something we Americans did manually, with the Met Data Correction Sheet, and, of course, now do via computer. Basic data for artillery is computed off of a set of "standard conditions" to provide a basis against which to measure deviations from standard, to account for the variations that occur in the real world.
To improve accuracy, you measure the conditions in the region between the guns and most likely targets, and using various tools, tables, etc, you calculate the deviations from standard conditions, and from that determine corrections that you apply to the basic data that account for the non-standard conditions, thus enhancing your accuracy.
You can do the same thing by "registering" the guns - but that requires shooting the guns. You pick a point, shoot standard data for it, correct your fall of shot until you hit the target and then measure the difference between the "should hit" (standard conditions data) and the "did hit" (all the messiness of the real world) to determine your corrections. Of course, those are only good for a narrow arc along the line of fire, as the impact of wind and rotation of the earth, for example, differ along different azimuths of fire. Plus, even if you have an enemy conveniently handy to use as a registration point there are some drawbacks to this method . Among those problems are giving away the position of the guns, getting clearance to shoot where you need to register (troublesome when you are fighting a war like the one we currently find ourselves in, i.e., a 360-degree one full of non-combatants), and the fact that you have to do it every time the conditions change much. Which means whenever a weather front comes through, or the sun comes up or goes down. When you register you are also shooting rounds that otherwise might be more usefully employed against the enemy, and, if you are registering on the enemy, well, he might get annoyed and shoot back, too.
So, artillerists came up with other ways to do things. This particular version is Swiss, for their license-built Swedish Bofors 105mm L42 gun. And in the current setup, for Charge One of the pointed HE round. That would be vice charge 2... or a different projectile, such as illumination, smoke, etc.
That dial in the upper right hand side is the heart of the device. You set off the wind direction and speed on that dial (in relation to the muzzle of the gun) and the linkages there transmit the requisite changes to the other rules, thus allowing you to gather your entry arguments and now determine your corrections to apply to the data.
More, excruciating detail is available here at Global Security...
Well done, guys.
Gunner
Heat
Duck
Up
Identified
Fire
On the way
Over
Reengage
etc, wash, rinse, repeat, err, you know what I mean...