To battleship specialists

[Baggers]

Hello.



Just to share a bit of love for BIG NAVAL GUNS!

(USS IOWA firing)

So, the main object of this little post will be the 16" navy gun, in turret of 3 guns, on Iowa-Class Dreadnought type of ship.

What's a Dreadnought? Well, it's what "Vulgus Peplum" wrongly call sometime a "Armored Battleship". It was in fact heavy armored, but not at the expense of a great top speed, and his main armament typically consist of a few turrets of some big guns of the same caliber.

Having 1-caliber for all main guns simplifies the task of the Firing Director, but we will see that later.

This concept of battleships is a bit outdated, and the few Dreadnoughts already afloat today (as museums...) are in the lasts days or retirement. Carriers, Missiles frigates now rule the Waves.


https://en.wikipedia.org/wiki/Dreadnought (If you want to know more about Dreadnoughts)

So, a 16-inchs turrets, it is:



Look simple, isn't? Well, not all firing operations are show, far from it!

Some videos of firing operations:
 

More firing, less talking! ^^

Now, we are confused. Why sometime they shoot all tubes of a turret simultaneously, and some other times, in short bursts?

Well, this as an complex answer, but this is a first view:

www.zhanliejian.com/navweaps/INRO_BB-Gunnery_p1.htm



The problem is: Hitting the opposite boat! (or the training target...)

So, the advantages of full salvo Vs partial salvos:

Salvos could be fired as full salvos, where all guns were discharged more or less simultaneously, as partial salvos, where half the main battery (usually either the forward after group) fired together, or as split salvos, where one gun of each turret fired together. Each system had its own advantages and disadvantages. Full salvos looked spectacular, but resulted in relatively large patterns which were difficult to spot and which arrived at relatively long intervals, thus making corrections difficult. Partial salvos reduced the pattern size, made spotting easier, and meant that corrections could be made (on the average) twice as often. Split salvos, due to the extreme separation of the guns, lead to the greatest accuracy and, theoretically, to the highest rate of fire as the director could fire as soon as any arbitrarily selected number of guns was ready to shoot.13

Technical solutions:

 

Quote

The Navy started experimenting with delay coils - simple mechanisms which prevented adjacent guns from discharging absolutely simultaneously - about 1935. Prior to the installation of delay coils, shells fired in salvo could travel in such a tight formation that they could actually collide, or "kiss" in flight, a phenomena which could be occasionally observed through binoculars. The velocity difference between projectiles traveling in salvo was so small - often less than ten feet per second - that shells fired very slightly late, and perhaps traveling very slightly faster than their counterparts, could spend a considerable amount of time in the confused air stirred up by the leading shells in the group. This increased their drag and made them fall short. An associated problem was that shells were often disturbed by the muzzle blast of an adjacent gun, especially if the muzzles were close together. The resultant wobble also increased the drag. The net result was a considerable number of "wild-shorts," i.e., shells which fell far enough short to be completely out of the pattern.14 Early installations of delay coils, which fired all guns at different times, created problems with turret whip, a problem which was, incidentally, rediscovered in the 1980s when Iowa and her sisters installed similar delays in order to decrease the effects of muzzle blast on pressure-sensitive equipment. Later installations fired both outside guns of a triple turret simultaneously in order to negate, or at least minimize, the effects of whip. The problem was, of course, inherently incurable in twin mounts, which is one reason that it was never used in 5"/38s.

 

In theses times, Navy warfare was still the business of Moustache Admirals, for wich a naval engagement was, you know, making 2 nices lines of enormous battleships and firing shells at a distance of 10km away all day.(with a accuracy of... We don't speak about accuracy.) When night come, we count the number of impacts on all the armored battleships, and the lesser impacted is sacred winner of the day!

So, to make realistics trainings for war, we make realistics training, with "target trains" in line, drawn by a lesser ship of some sort:




(Well, they sure look ragged now, aren't they, old chap?)

But sometime, things go wrong...

 

Quote

The use of a towed target train sometimes posed laughable difficulties. In one case a large caliber projectile cut the towline early in the exercise and the target train slowed rapidly to a stop. The result was complete confusion in the battle line. Some ships took no account of the problem at all, their salvos continuing a majestic march into completely empty ocean (some suspected that this was because they were actually tracking the towing ship instead). Other ships adjusted their fire to remain on the slowing target train, but got hopelessly confused as the targets closed up on each other and began to overlap. The net result was utter chaos, followed by a lengthy argument about exactly how the practice should be scored. Clearly, disrupting an enemy battle line could cause as many problems as it solved.

 

Well, with enemy ships not making a regular line like they should and questionnable reliability of armament, the Firing Director task is not esay!

 

Quote

The reliability of the guns always appears to have varied markedly from ship to ship. In 1942, USS Idaho undertook an exercise deliberately designed to determine ". . . the ability of battleships to maintain an adequate rate of fire under conditions simulating a protracted engagement," expending 597 rounds in 156 salvos. The average salvo interval was 1 minute, 24 seconds, but only 20 of these were full six-gun salvos; the average was 3.82.

 

 

But back at firing director: Today, everyone guess well all naval guns have the best firing computer and so, but back in the old days? How do they estimate distances, angles, speed of target? And calculate all you need to fire accurately when all ships are moving in the waves?

Don't panic! No need for an hasardous finger guess, back in theses times we already have... firing computer!

Again, it's not what you thinh. No, not punch card, still older...



 

"Mechanical computers!" Nothing numeric inside, only cams and pins! The only computer really lighting-fast!

https://arstechnica.com/information-technology/2014/03/gears-of-war-when-mechanical-analog-computers-ruled-the-waves/

OK, so we have 15 guys turning whells and so, but when do we fire?

When the Firing director say it! Long gone are the time where each turret act on his own! All the main armament are directed from the main bridge, and fire simultaneously on the officer order!

And seasickness is coming...



http://www.godfreydykes.info/Gunnery%20Directors%20Part%20II.pdf

Never heard of roll and tipping? Not an easy task to keep the opposite boat well aligned whit the little cross...

Firing accuracy is therefore in the hand-eye coordination of the firing director, hoppefully sober today (by luck). This can explain many things...

But! You can not stop progress! So here come the "vertical stabilisator"

 

 

It's more or less that, and make even an early aperitiffed Moustache Admiral able to use correctly his targeting device. The firing computer will suspend a fraction of second the firing order for accomodating the roulis, and BOOM!

Cheers!
 

Edited November 22, 2018 by Baggers
broken links repaireds.

[Baggers]

Now in full (bad) english ^^ Sorry, it took a bit of time as the Edit tools of this forum isn't very instinctive for this sort of posts.

I was especially impressed by the "mechanical" computers of the Navy, very steampunk ^^

Sorry for my poor english, but at least all sources and videos are in regular english ^^

Fell free to correct me on any point.

Hope this little glance at "what is like to fire a Naval Arty" pleased you. ^^ It will certainly not learn anything to peoples here, but I think it can be used as a draft for a first "catch eye" on the subject.

[RichardMcCor]

My great great grandfather Arthur John McCormack was M.D. At wolseley motors during WW1 where they were responsible for many RN and ship related products like building 27 fire control directors for british battleships. in WW1. I have lots of wolseley history but i'm not sure it helps in the game development.

[Supervark]

Have a great interest in this subject and have most of the Brassys Annuals from 1887 upto 1921 still missing a few years as they are hard to come by. Will be happy to send any information.

[druskies]

Hello,

I realize I am a bit late to the post, but I have a Bachelor's degree in history and I do focus on naval and early aerial warfare including the time period you are looking for. I am also a gamer and would love to help anyway I can.

Thanks.

[TechnoSarge]

I spent ... a few... decades with naval miniature wargaming. I know game players like to be armchair ship designers. What owners of the books shown in above posts know is that putting a ship together is 'way more complicated that choosing hull modules in SOTS. Every choice affects everything else to be chosen.

I spent a lot of time with my set of books creating empirical formulae for the different warship categories, based on actual ships built and operated by the world's navies. (much better than working directly with naval architecture principles, as in "Modern Ship Design" by M.I.T. professor Gilmer). This was aimed at letting me make plausible design decisions, based on the technologies available at the time, for never-designed warships.

Y'know - I gave it up. There's a free tool by some guys who have done all the work!  It's illuminating to discover that your imagined ship is not sufficiently stable, or lacks adequate hull volume to carry out needed functions! The interface is not the friendliest, but I trust the output. Visit http://www.springsharp.com/    

My advice: hire those guys for working on your game's shipyard. Your 3D model maker will be wonderful, I'm sure. And with good scientific integrity behind the design work, your game can not only be a game and a history lesson, but a revelation to those people who have yet to clamber below decks on an old warship and wonder, "Huh! I wonder why they did THAT!"