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Bart B. · April 1, 2009, 03:52 PM

Here's two main links to the US Navy's large caliber shipboard guns:

Naval Ordnance & Gunnery Vol. 1; complete information on both gun mounts and gun turrets. Sub links have much details on what really goes on with these monsters. Chapters 6 and 7 are great.
http://www.eugeneleeslover.com/FC-ORDNANCE.html

Naval Ordnance & Gunnery Vol. 2; all the main stuff about the radars, computers and machinery used to aim and load main battery shipboard systems. Chapters 19 and 20 are most interesting.
http://www.eugeneleeslover.com/FIRE-CONTROL-PAGE.html

Petty Officer 2nd Class Slover has put together the best on-line information I've seen on US Navy main battery systems. Reading and knowing virtually all this information back in the late 1950's and early 1960's was important if one wanted to be advanced to Petty Officer 1st Class or Chief Petty Officer.

It all kind of went like this when a shore fire control party got a call for fire from some infantry outfit ashore. The target's position had already been set into the MK 8 Rangekeeper in main battery plot. When everything looked pretty good, it started.........

"Shore action starboard! All guns, main battery. High capacity, full charge, fuse quick! B turret center gun, 1 round load for spotter correction. All turrets, all other guns load and stand by for shore bombardment action!" sang out the main battery plotting room's Chief Petty Officer after the Gunnery Officer made final decisions on what to to then told the Chief to call for action. Meanwhile the MK 8 Rangekeeper ships range, bearing, and target plotting operators cranked knobs and watched dials for own ships position quickly be what's needed to properly aim the guns at the target's calculated postion.

Meanwhile, folks on the bridge and fire control towers were taking range and bearing readings to known shore objects to triangulate an accurate ships position to the target position on the charts. In fact, during shore bombardment, ships speed was set into the range keeper manually at zero. The target point ashore was cranked in to equal ships speed but whose course was 180 degrees out from own ships course. Ballistic calculations were more accurate doing it this way. They calculated the actual bearing and range to the target and the rangekeeper operators made sure their machine had the same numbers. If they didn't, small corrections to target course and speed would be made until they did match. When it did consistantly match, "Plot set!" was made by the battery chief to the gunnery officer.

When B turret's turret captain phoned back to main battery plot: "B turret center gun loaded!" the Chief told the stable vertical (held the gyro to give the true vertical for aiming guns as well as firing keys, or triggers) operator whose hands were on the firing keys: "B turret center gun....Shoot!"

The stable vertical operator would close the salvo warning key twice quickly with his left hand to sound a pre-firing klaxon in the turret as well as in other key stations on board. Two short blasts on the salvo warning klaxon was followed one second later by the stable vertical operator used his right hand for closing the firing key now connected for B turret. It took about 1 second from closing the key before all hell broke loose, the ship shuddred and a God awful "booooooommmmmm" was heard every where.

As soon as the 16-inch gun counter recoiled 3 feet back into battery and elevated back to its load position, the plug would be dropped and gas ejection air blew all the smoke and residue out the muzzle. When the gun captain could see daylight through the 66-foot long hole: "Bore clear. One round expended. No casualties." was the report from the gun captian to the turret captain in the turret's control room which he passed on to main battery plot.

Many seconds later the main battery plotting room range operator who started his stop watch when the round was fired and knew how long the projectile's time of flight was, would radio the spotter ashore watching the impact area through his binoculars "Standby!" which meant in about 5 seconds the round would hit. "Splash!" was the call the spotter was waiting for; he would see the round's explosing on impact, then make his spot corrections based on his position relative to the target. He radioed back to the ship; "Drop 150, left 4 mils, fire for effect!!!" Which meant the shore fire control party had enough confidence in the ship's crew to do well enough that further spots weren't needed. The target needed to be destroyed now!

Back in the ship's plotting room, they would convert the spots from the spotters position to what was need from the ships position using a round calculator called a Mil Spot Converter. The rangekeepers bearing and range operaters would make spot corrections to change gun orders just enough to move the impact point. "Add 200, right 2 mils!" would be given to the range and bearing operators then they cranked them in on the spot correction knobs. As soon as the rangekeeper's gun order dials had quit shaking from the spot adjustments and settled down, the operators would say "Bearing set." "Range set." The battery Chief would tell the gunnery officer "Plot set!"

The gunnery officer was satisfied with everything going on, he would then tell the battery Chief to fire for effect. So the Chief phoned everyone in the battery saying: "Shore action port, main battery, all guns, high capacity, salvo fire, full charge, fuse quick. Load and be ready!! Some 66 men in each of a battleship's turrets would move 9 projectiles and 54 bags of powder into gun breeches. The fire control switchboard operator would set a couple dozen turret control switches to get orders from the rangekeeper and firing circuits from the stable elements. When all turrets reported ready back to main battery plot, everyone got ready for that klaxon to sound again.......

"Shoot! Shoot! Shoot!" was what the stable vertical operator heard then he closed the salvo warning key twice more, then several hundred people on board who heard those salvo warning klaxon's honking quickly plugged their ears. The firing key was closed and a second later, all hell broke loose in the form of nine 1,900 pounders going up those barrels headed for some poor target ahore. "Bababa- bababa- bababooooooooooommmmmmmmmm" all within one second. Dust and rained down from the over head cables. Coffee cups rattled in their racks. Light bulbs loose in their sockets would fall out. Pencils jumped on the desks they were on. The whole ship went to about 4 on the Richter scale. And that 45,000 ton battleship moved sideways in the water about two thousandths of an inch; .002-inch. That's all.

It all happened again about 40 seconds later. Then again. And again. And again...... until those blessed words came back from the shore fire control party's spotter: "Cease fire! Cease Fire. Target destroyed." And a few mintes later, the shore fire control party would get a call from some infantry unit that another target was found, so the beleaguered US Army platoon's second lieutenant radioed the shore fire control party the coordinates of a column of enemy tanks moving towards him but were behind a high hill between them and the ship. But only three guns were needed for those tanks. No more celebrating; back to work. So the plotting room sets up a new target on the rangekeeper after shifting its ballistics section to "reduced charge" to arc the projectiles over that hill and down on the tanks. Turret crews get ready to load only four bags of powder instead of the normal six, then pay attention to the new orders: "Shore bombardment, port. Main battery, C turret. High capacity, reduced charge for reverse slope target, fuse quick! C turret center gun, 1 round load for spotter correction. All other guns stand easy"

As Paul Harvey (bless his departed soul) said so many times: "Now you've heard the rest of the story."

Bart B.
Chief Fire Controlman
USN Retired

April 1, 2009, 03:52 PM	#47
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Here's two main links to the US Navy's large caliber shipboard guns: Naval Ordnance & Gunnery Vol. 1; complete information on both gun mounts and gun turrets. Sub links have much details on what really goes on with these monsters. Chapters 6 and 7 are great. http://www.eugeneleeslover.com/FC-ORDNANCE.html Naval Ordnance & Gunnery Vol. 2; all the main stuff about the radars, computers and machinery used to aim and load main battery shipboard systems. Chapters 19 and 20 are most interesting. http://www.eugeneleeslover.com/FIRE-CONTROL-PAGE.html Petty Officer 2nd Class Slover has put together the best on-line information I've seen on US Navy main battery systems. Reading and knowing virtually all this information back in the late 1950's and early 1960's was important if one wanted to be advanced to Petty Officer 1st Class or Chief Petty Officer. It all kind of went like this when a shore fire control party got a call for fire from some infantry outfit ashore. The target's position had already been set into the MK 8 Rangekeeper in main battery plot. When everything looked pretty good, it started......... "Shore action starboard! All guns, main battery. High capacity, full charge, fuse quick! B turret center gun, 1 round load for spotter correction. All turrets, all other guns load and stand by for shore bombardment action!" sang out the main battery plotting room's Chief Petty Officer after the Gunnery Officer made final decisions on what to to then told the Chief to call for action. Meanwhile the MK 8 Rangekeeper ships range, bearing, and target plotting operators cranked knobs and watched dials for own ships position quickly be what's needed to properly aim the guns at the target's calculated postion. Meanwhile, folks on the bridge and fire control towers were taking range and bearing readings to known shore objects to triangulate an accurate ships position to the target position on the charts. In fact, during shore bombardment, ships speed was set into the range keeper manually at zero. The target point ashore was cranked in to equal ships speed but whose course was 180 degrees out from own ships course. Ballistic calculations were more accurate doing it this way. They calculated the actual bearing and range to the target and the rangekeeper operators made sure their machine had the same numbers. If they didn't, small corrections to target course and speed would be made until they did match. When it did consistantly match, "Plot set!" was made by the battery chief to the gunnery officer. When B turret's turret captain phoned back to main battery plot: "B turret center gun loaded!" the Chief told the stable vertical (held the gyro to give the true vertical for aiming guns as well as firing keys, or triggers) operator whose hands were on the firing keys: "B turret center gun....Shoot!" The stable vertical operator would close the salvo warning key twice quickly with his left hand to sound a pre-firing klaxon in the turret as well as in other key stations on board. Two short blasts on the salvo warning klaxon was followed one second later by the stable vertical operator used his right hand for closing the firing key now connected for B turret. It took about 1 second from closing the key before all hell broke loose, the ship shuddred and a God awful "booooooommmmmm" was heard every where. As soon as the 16-inch gun counter recoiled 3 feet back into battery and elevated back to its load position, the plug would be dropped and gas ejection air blew all the smoke and residue out the muzzle. When the gun captain could see daylight through the 66-foot long hole: "Bore clear. One round expended. No casualties." was the report from the gun captian to the turret captain in the turret's control room which he passed on to main battery plot. Many seconds later the main battery plotting room range operator who started his stop watch when the round was fired and knew how long the projectile's time of flight was, would radio the spotter ashore watching the impact area through his binoculars "Standby!" which meant in about 5 seconds the round would hit. "Splash!" was the call the spotter was waiting for; he would see the round's explosing on impact, then make his spot corrections based on his position relative to the target. He radioed back to the ship; "Drop 150, left 4 mils, fire for effect!!!" Which meant the shore fire control party had enough confidence in the ship's crew to do well enough that further spots weren't needed. The target needed to be destroyed now! Back in the ship's plotting room, they would convert the spots from the spotters position to what was need from the ships position using a round calculator called a Mil Spot Converter. The rangekeepers bearing and range operaters would make spot corrections to change gun orders just enough to move the impact point. "Add 200, right 2 mils!" would be given to the range and bearing operators then they cranked them in on the spot correction knobs. As soon as the rangekeeper's gun order dials had quit shaking from the spot adjustments and settled down, the operators would say "Bearing set." "Range set." The battery Chief would tell the gunnery officer "Plot set!" The gunnery officer was satisfied with everything going on, he would then tell the battery Chief to fire for effect. So the Chief phoned everyone in the battery saying: "Shore action port, main battery, all guns, high capacity, salvo fire, full charge, fuse quick. Load and be ready!! Some 66 men in each of a battleship's turrets would move 9 projectiles and 54 bags of powder into gun breeches. The fire control switchboard operator would set a couple dozen turret control switches to get orders from the rangekeeper and firing circuits from the stable elements. When all turrets reported ready back to main battery plot, everyone got ready for that klaxon to sound again....... "Shoot! Shoot! Shoot!" was what the stable vertical operator heard then he closed the salvo warning key twice more, then several hundred people on board who heard those salvo warning klaxon's honking quickly plugged their ears. The firing key was closed and a second later, all hell broke loose in the form of nine 1,900 pounders going up those barrels headed for some poor target ahore. "Bababa- bababa- bababooooooooooommmmmmmmmm" all within one second. Dust and rained down from the over head cables. Coffee cups rattled in their racks. Light bulbs loose in their sockets would fall out. Pencils jumped on the desks they were on. The whole ship went to about 4 on the Richter scale. And that 45,000 ton battleship moved sideways in the water about two thousandths of an inch; .002-inch. That's all. It all happened again about 40 seconds later. Then again. And again. And again...... until those blessed words came back from the shore fire control party's spotter: "Cease fire! Cease Fire. Target destroyed." And a few mintes later, the shore fire control party would get a call from some infantry unit that another target was found, so the beleaguered US Army platoon's second lieutenant radioed the shore fire control party the coordinates of a column of enemy tanks moving towards him but were behind a high hill between them and the ship. But only three guns were needed for those tanks. No more celebrating; back to work. So the plotting room sets up a new target on the rangekeeper after shifting its ballistics section to "reduced charge" to arc the projectiles over that hill and down on the tanks. Turret crews get ready to load only four bags of powder instead of the normal six, then pay attention to the new orders: "Shore bombardment, port. Main battery, C turret. High capacity, reduced charge for reverse slope target, fuse quick! C turret center gun, 1 round load for spotter correction. All other guns stand easy" As Paul Harvey (bless his departed soul) said so many times: "Now you've heard the rest of the story." Bart B. Chief Fire Controlman USN Retired Last edited by Bart B.; April 1, 2009 at 05:19 PM.