The bar stool

The bar stool

Joined: October 10th, 2005, 8:42 pm

September 15th, 2009, 10:40 pm #1

The emblem for a Fire Control Technician Guns (FTG) is affectionately called a bar stool, mostly because that is what it looks like to a sailor. The top part is an optical rangefinder. The bottom is a tripod supporting the rangefinder.
The job of the Fire Control Technician is, among other things, to make sure the target and the shell reach the same location at the same time. For a Fire Control Guided Missile (FTGM) they make sure the target and the missile arrive together at a pre-determined location for an explosive rendezvous.
In the early days of black powder cannons the gunners mate had to do it all. He would have to know about how much powder was needed to get a cannon ball a certain distance. He would have to estimate this distance himself by sight. As the ship was usually rolling with the seas he would have to fire on the up roll to get the maximum distance. If he missed he would add or use less powder for the next shot. It usually took several shots for him to get the final solution, all this while being shot at by the other ship.
As weapon technology improved with pre-determined powder charges, fixed ammunition and more accurate cannons, the gunner still had to estimate the distance.
A better more accurate method was needed. Radar had not even been thought of at the time. The British Admiralty sponsored a competition to design a rangefinder for its battleships in 1892. Apparently some primitive rangefinders were being experimented with at that time using optical lenses and mirrors. We wont get into how they work exactly but earlier versions used on the ships were sometimes almost 20 feet long to get any kind of accuracy. If you look at the gun mounts on the WWI and WWII ships you will see what looks like two round things sticking out of the sides of the gun mount. These are the rangefinders. As manufacturing techniques improved the size grew smaller and more manageable.
One of my duties during the beaching detail was to use an optical rangefinder and call out distance to the beach. This let the skipper know exactly when to release the stern anchor, a much more reliable method than estimation. This device was a metal tube about a yard long that was supported by a harness much like a flag holder would support a flag while marching. One would look through a pair of eyepieces much like binoculars to see the target (beach) and could read the distance to the target in yards. Accuracy of a few yards was acceptable. Although my ship did have radar, sea return, noise and terrain often cluttered the radar display making accurate distance measurement difficult. Also, the radar was a surface search type and could not measure things too close in.
With todays radar ranging and laser technology the optical rangefinder has went the way of other old technology but remains a stepping stone to our modern equipment.


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Joined: December 22nd, 2008, 3:07 pm

September 16th, 2009, 2:22 am #2

Per usual you have excellent information to offer to the thirsty. Would you please expand on the rest of your beach details? Thanks!
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Joined: October 10th, 2005, 8:42 pm

September 16th, 2009, 4:03 pm #3

Now this is no ....
One thing I learned at the police department, anythig put in writing may be used against you later. Naturally, like all good sailors on the beach (liberty), I behaved myself, never went to off limits places, drank in moderation, never got in a fight, stayed away from bars of ill repute, never socialized with the local ladies, did not smoke or gamble, never used profanity, and never showed up for muster the next morning still intoxicated from the night before.
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Joined: January 21st, 2005, 9:59 am

September 16th, 2009, 4:57 pm #4

SURE YOU WERE IN THE NAVY
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Joined: February 12th, 2009, 9:41 am

September 16th, 2009, 6:50 pm #5

What did you expect from a "twidget" ???
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Joined: February 27th, 2005, 12:56 pm

September 16th, 2009, 7:17 pm #6

Now this is no ....
One thing I learned at the police department, anythig put in writing may be used against you later. Naturally, like all good sailors on the beach (liberty), I behaved myself, never went to off limits places, drank in moderation, never got in a fight, stayed away from bars of ill repute, never socialized with the local ladies, did not smoke or gamble, never used profanity, and never showed up for muster the next morning still intoxicated from the night before.
I'm glad you found some fun in a bad sitution, I'm sure your liver and knuckle's might tell another story.

Bob R.
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