Gun ranging in WW1 and WW2

[Last Hussar]

In the naval battles of the first half of the 20th Century, part of ranging was watching for the splash of the shells, and using that to correct the elevation.

If 2 or more ships were engaging the same target, how did they know which splashes were theirs - for instance at the River Plate in 1939?

[fred.]

They struggled

Also when firing guns of different calibres

I do assume in a fairly small engagement that spotters up on the masts could actually track the flight of the bigger shells through the air - so would have a decent idea which splashes were theirs.

But then add in smoke from funnels and guns and fires

Have a look at British vs German gunnery training in WWI. The British favoured as many shells out as possible the Germans actually trained to hit stuff.

This is why naval radar was such a game changer

[Lord Kermit of Birkenhead]

Sometimes dye was put into the burster. WWI ships in the late war had bearing markers on the turrets and a range clock on the main mast or elsewhere. Otherwise seems to have been guesswork based on time of flight. Not aware of any naval shells above light AA having a tracer element.

[steve_holmes_11]

In the naval battles of the first half of the 20th Century, part of ranging was watching for the splash of the shells, and using that to correct the elevation.

If 2 or more ships were engaging the same target, how did they know which splashes were theirs - for instance at the River Plate in 1939?

Observing fall of shot, and correcting was a technique borrowed from land warfare.
It worked reasonably well when your target wouldn't move fast (Bunkers, supply depots, enemy artillery batteries, key infrastructure like crossroads, bridges, rail yards and harbours).

In a naval context, predreadnoughts and gun crews aiming it was hopeless.
Effective engagement range was around 3,000 yards.
This was massively increased by the gradual introduction and improvement of centralised fire control.

Stick a guy with a rangefinder as high up as possible (Those Gardner guns up there were wasting space and weight).
Rig a telegraph down to a fire control centre, where lots of calculations take place (people or machines doing the sums).
Another telegraph connects to the main turrets and tells them where and when to shoot.

This is still a bit ropey if you have just four main guns, and two or three calibres of lesser guns all making plashes and noise.
So you re-design your fighting ships with more guns in a uniform main calibre.
Now you're in business to start landing salvos and ladders to get a good idea of range.
The loop is Estimate range and bearing, clever blokes apply offsets to lead the target and create the ladder, shoot, observe splashes, corfect and repeat.

Apologies for the lengthy background.

This works reasonably well when your fleets are forming nice tidy lines, like proper gents, and steaming in uniform directions.
It also helps that most lines can manage about 20 knots.
The beastly hun goes and spoils it all by practicing (pah!!) their battle turn manoeuvre - how's a chap to know where the target will be in 45 seconds time...
So advanced fleets have to devise alternate means to shoot with accuracy.

I realise I've not answered your question yet.
I have led the witness to the point where land artillery shoot and spot isn't the only game in town.

Imagine you're the "big navy" with the advantage on numbers.
How can you make this count?
The original post observer that everybody shooting willy nilly isn't efficient.
Here are a few answers.

Cooperation
Similar to one gun of a battery shooting for range, then the rest firing for effect.

Recall those pictures of coal fired fleets sailing in line, those big range clocks on the masts and direction markers on turrets.
This allows ships to copy a neighbour's homework.
Maybe your spotting top got shot out, or your computers are on the blink, maybe next-door ship is a crack shot and found the range, or maybe you're deliberately saving your powder while your crack shot ship marks the target.
A bloke on your bridge with binoculars then reads off their range and bearing, and sends this to your control room.

The Russians (of all navies) created an advanced version of this.
It used an early version of "talk between ships" to interlink three predreadnoughts into a compoud firing unit with 12 x 12" guns.
This combination saw off the Goben/Yavuz on several occasions.


Distinction (Our splashes are different)
Navies tried sticking bags of dye into their shells.
This colour coded the splashes from different ships.

I can only imagine the difficulty of picking these out in the heat of battle.
The Italians and Japanese were still using this technique during WW2 - maybe others did too.

Don't confuse this with the film Kelly's Heroes where Donald Sutherland's character Oddball shoots shells loaded with paint.
The naval dye bag formed a tiny proportion of the payload of the shells in question.


Better Range-finding
Once you've resolved discrepancies between your rangefinder and your gun's idea of 15,000 yards (Pretty reliable by WW2), you can shoot based on observed range.
It helps a lot of you have really sharp optics (Germany / Japan), lots of optics (Italy), Easy to use Optics (Royal Navy / US Navy), and ultimately fire control radar.

There have also been massive refinements to the computer portion of the fire control system, and ships are going much faster.
Both of these reduce the value of fall of shot observation in the shooting calculations.

If you can shoot without waiting to observe fall of shot you gain several advantages.
1. Faster fire at longer ranges - It can take up to a minute for a maximum range shot to land. By this time ww2 fast battleships may have changed their relative position by a nautical mile. Fall of shot has marginal benefits and a negative impact on your rate of fire.
2. Observers (or radar) concentrate completely on enemy range and relative bearing - improving your input values to the system.


Shoot Faster
This applies mainly to modern guns of 6" or below.
I've included it since the original pose cites River Plate with two 6" cruisers engaged.
The better navies are getting 8-10 shells per tube from their 6" batteries by ww2.

The US and Royal Navies have focused production on "Light" cruisers, judging rapid fire to fit their doctrine better than fewer bigger bangs from the 8" guns of a "heavy" cruiser.
Other factors apply - The US and Royal Navies had most battleships for doing "proper big bangs".
Many smaller navies expected their 8" cruisers to engage enemy capital ships for a few minutes to level the playing field a little.

Anyway, the light cruisers are shooting so fast that fall of shot in only a concern at their extreme ranges.
Closer in, they return to the cruiser function that an admiral from 1905 would recognise.
Blanket the enemy with shells and suppress anything outside the armour belt.

With this in mind, Ajax and Achilles were able to operate effectively as one detachment, while Exeter with different guns, operated alone.


Congratulations if you ploughed through all that stuff.

In Brief:
Multiple ships shooting one target was a big factor for a relatively brief period.
The admirals, boffins and shipwrights devised a number of solutions.

[Lord Kermit of Birkenhead]

Steve you have missed very few bits. But WWI British ships got directors aloft and a Transmitting Station below. The TS was intended to maintain a plot - of the enemy course and speed to predict the range. By 1917/8 both major navies were firing the "ladder" - 1/2 slavos 3/4/5 tubes aimimng to drop one under, one over and one on. Germans found the range faster, British held it better.

[Last Hussar]

Reading all this (including all of Steve's!) the answer appear to be "We're the Red splashes, any other colour is someone else" with a bit "given the time between 'Bang' and 'Splash', those ones are probably ours."

The problem with 'one under, one over and one on' is you need to know which ones are yours!

The question was brought on by playing a lot of 'Atlantic Fleet' on the computer.

[Duke Speedy of Leighton]

My Grandad was secondary gunnery officer (starboard side) on HMS Duke of York at the Battle Of North Cape. 5.5" guns
8 secondary guns in four turrets, front two firing star shell, others were firing for effect.
Fired 96 rounds at the Scharnhorst, 'missed with every single one of them'!..
The range was 15 miles. And it was dark.

Later in the battle port guns were told to stop firing, as they were too accurate and hitting the bridge, so main guns could not see the bridge to aim!

He was up in the spotting tips, said it was bloody cold and miserable, 3am on Boxing Day, tea froze on the way up to you, and a 15" shell passed UNDER him, cutting a radar cable. Someone got a medal for getting up his mast and splicing it back together.

Never actually discussed how he aimed, just called bearing, range, over, under, hit.

[steve_holmes_11]

That's "Barehands" Bates

https://military-history.fandom.com/wiki/Harold_Raymond_Kingsmill_Bates


In the words of the Red Dwarf crew - "What a guy!"

[Duke Speedy of Leighton]

Ooh, nice one Steve!

[slugbalancer]

Big Gun Battles: Warship Duels of the Second World War by  Robert C Stern

[paulr]

A very good summary Steve

...
He was up in the spotting tips, said it was bloody cold and miserable, 3am on Boxing Day, tea froze on the way up to you, and a 15" shell passed UNDER him, cutting a radar cable. Someone got a medal for getting up his mast and splicing it back together.
...

Did you mean an 11" shell, returning to pedants' corner now

[Duke Speedy of Leighton]

11". You are correct.

It's been a long day at work

[steve_holmes_11]

If we're doing pedantry, the story of "Barehands" Bates has been somewhat revised as official records outran their official purdah.


The public story (including citation for decorations) was altered to avoid revealing too much about RN radar.
See also "night fighter pilots on a carrot diet".
Tasty fodder for Jerry's (limited) intelligence boys.

People were told that he restored the signals by "Holding both ends of the cable together".
I assume they dug out some old salt form the age of sail to concoct that cover story, as it chimes with splicing cables.
Any maritime spark would spot the obvious problem with holding cables in contact - especially with bare hands.


Records reveal a rather different story.
A shell had messed with the radar's ability to rotate (I'm not sure how).
Captain Bates (about to earn his Barehands moniker) scaled the mast.
He then bashed, shook and twisted until the radar started tracking again.

The citation was written up as a cable repair, and "Barehands" was embellished at the press conference.


Three things to take away form this story:
 * It is possible to acknowledge your heroes without spilling the entire saucerful of official secrets.
 * Never climb up a steel ladder attached to a steel mast, in the arctic winter with bare hands.
 * Even with gloves, Captain Bates clearly possessed 68 pounder carronade shot where we mere mortals have soft warm goolies.