Anybody up to speed with naval gunnery?

[spikey]

Unless my hearing's even worse than I think, at 3'05" the voiceover on this video says that the 12.7cm gun on this ship can lob a shell over 50 miles.  Can that be so, and if indeed it can, what manner of shell are they firing and how do they lock on to the target at such a range? 

 

 

[Kickstart]

Seems to be correct, although whether that is a round that is only propelled by at the gun I do not know

 

Glossy brochure below. Range is given at over 100km

 

https://www.leonardo.us/hubfs/Leo Downloads/OTO_127_64_LW_VULCANO_LQ_mm08728_.pdf

 

All the best

 

Katy

[simontaylor484]

I'm going to suggest over the Horizon radar i wouldn't know what the propellant would be i would assume they could interchange the type of shell between armour piercing and high explosives

[Michael Hodgson]

I don't know what range the Royal Navy's guns have, but I think the Channel Islands are far enough away from Porstmouth that we'd still have to send a gunboat if we were expecting to have trouble with French fishermen.

[PenrithBeacon]

https://www.baesystems.com/en/product/vulcano-precision-guided-munitions

I get the impression that they are more like guided missiles than conventional shells 

[Nearholmer]

4 hours ago, spikey said:

how do they lock on to the target at such a range? 

 

The military equivalent of dropping a pin on google maps, then let the computers get on with it, communicating via satellite, and other means. The gun is self loading, and the boat can probably be controlled by a bloke at home in bed in Brentford. If mega-precision is needed, they can probably "illuminate" the target using drone-borne systems, so that the projectile can "see" it.

[Siberian Snooper]

The range of our 4.5 inch guns on the type 21s was around 8 miles. They and all subsequent guns are self loading and with similar rates of fire.

 

There must be one helluva lot of propellant to lob a shell 50 miles, unless it's a missile.

 

 

[The Stationmaster]

The long range would make a lot of sense for attacking a target on land as (in many cases) it is not going to move and the ship will know exactly where it is in relation to the target.  It only makes sense against another target at sea if the round/missile has some sort of guidance or homing system and the vessel firing it is receiving accurate target position information from another source.

 

PS But the ship itself has been a bundle of problems for the German navy

 

https://spectrum.ieee.org/riskfactor/computing/it/new-german-frigate-fails-tests

Edited May 9, 2021 by The Stationmaster

[Tankerman]

3 hours ago, Siberian Snooper said:

The range of our 4.5 inch guns on the type 21s was around 8 miles. They and all subsequent guns are self loading and with similar rates of fire.

 

There must be one helluva lot of propellant to lob a shell 50 miles, unless it's a missile.

 

 

 

When I was serving my electrical apprenticeship at Falmouth docks, a very long time ago now, one of the electricians had been on one of the prewar Town class cruisers, the triple turrets were the same as those on HMS Belfast. 

 

I can remember him telling me that in action the gun crews were expected to maintain a rate of fire of 10 rounds per minute per gun. This was done with semi hand loading of the shells and hand operation of the breech block. He also told me that the reason the centre gun is mounted further back than the outer guns is that the shell from that gun wasn't affected by the blast from the outer two.

 

Concerning the range of conventional shells. The longest range hit on a ship from another ship is generally believed to be that obtained by HMS Warspite when one of her 15 inch shells hit the Italian battleship Giulio Cesare at a range of 26,000 yards, or approximately 15 statute miles, during the Battle of Calabria in 1940, when both ships were steaming at around 25 knots.  

 

I hope this has been of interest.

[alastairq]

14 hours ago, PenrithBeacon said:

https://www.baesystems.com/en/product/vulcano-precision-guided-munitions

I get the impression that they are more like guided missiles than conventional shells 

 The Vulcano seems to be the answer?

I have to admit, on reading the above article,  the first picture that formed in my mind was, why are they using ducks to get longer range? Why ducks? Why not parrots? Or geese? 

Oh, sorry, they tried Parrots over a century ago....

[Michael Hodgson]

1 hour ago, Tankerman said:

Concerning the range of conventional shells. The longest range hit on a ship from another ship is generally believed to be that obtained by HMS Warspite when one of her 15 inch shells hit the Italian battleship Giulio Cesare at a range of 26,000 yards, or approximately 15 statute miles, during the Battle of Calabria in 1940, when both ships were steaming at around 25 knots.  

 

Very good shooting at that range to hit a target with a conventional shell. 

I wonder how many shots missed before that one landed though.

[chris p bacon]

I think I've posted this here before.

Dad was a 6th Engineer on British Strength in April 1941, they were in convoy from just off Oban to Curacao, after just 150 miles the escort turned away and headed back and the ships were ordered to scatter for the rest of the journey. after a week+ they were picked up by Scharnhorst and from 12 -14 miles away they put a shell into B Strength to disable her. Although that might be thought to be unlucky only a few hours beforeScharnhorst had done the same to another tanker 'Athelfoam' and the direct hit from a similar distance had killed 7 merchant men.

After a night on Scharnhorst he was transferred to the Altmark (supply ship) for the jorney back to France and internment.

[spikey]

3 hours ago, The Stationmaster said:

PS But the ship itself has been a bundle of problems for the German navy ...

It seems from various bits and bobs on German news sites over the last year or so that just about every ship the Kriegsmarine Bundeswehr has nowadays is causing them grief.  Herr Dönitz müssen sich in seinem Grab drehen.

 

 

[Michael Hodgson]

Maybe that's why he signed the surrender?

[Tankerman]

1 hour ago, Michael Hodgson said:

Very good shooting at that range to hit a target with a conventional shell. 

I wonder how many shots missed before that one landed though.

 

Since she was chasing the Giulio Cesare she was probably firing alternate salvos from just her two forward turrets. The rate of fire of the RN 15 inch gun was between 1 and 2 rounds per minute, depending on the proficiency of the gun crew. I don't know the length of time the battle lasted, but it was probably no more than 30 minutes, so somewhere between 120 and 150 rounds. From memory the maximum life of the barrel of each gun was about 350 full cordite charges.

 

It is sometimes forgotten that the shell and the cordite charge were loaded separately and that the gun had to be returned to the horizontal to reload  The sequence, starting from a loaded gun being horizontal, was elevate the gun to the appropriate angle called for by the director, in the case of the Warspite, to a maximum of 30 degrees, fire the shell, bring the gun back to the horizontal, open the breech, insert the next shell then the cordite charges, close the breech, re-elevate the gun.

 

 

Edited May 9, 2021 by Tankerman
additional info

[Tankerman]

28 minutes ago, spikey said:

It seems from various bits and bobs on German news sites over the last year or so that just about every ship the Kriegsmarine Bundeswehr has nowadays is causing them grief.  Herr Dönitz müssen sich in seinem Grab drehen.

 

 

 

Ie the German Navy is in that bad a state Donitz is probably turning as fast as an aircraft engine.

[The Johnster]

2 hours ago, chris p bacon said:

I think I've posted this here before.

Dad was a 6th Engineer on British Strength in April 1941, they were in convoy from just off Oban to Curacao, after just 150 miles the escort turned away and headed back and the ships were ordered to scatter for the rest of the journey. after a week+ they were picked up by Scharnhorst and from 12 -14 miles away they put a shell into B Strength to disable her. Although that might be thought to be unlucky only a few hours beforeScharnhorst had done the same to another tanker 'Athelfoam' and the direct hit from a similar distance had killed 7 merchant men.

After a night on Scharnhorst he was transferred to the Altmark (supply ship) for the jorney back to France and internment.

The Germans had radar at least as highly developed as ours in the early years of the war, but their concept of what it was for was for directing naval guns rather than incoming aircraft.  Thus their gunnery was better than ours, as suggested by your father's experience on British Strength.  Bismark, as is well known, destroyed Hood with only the second shell she'd ever fired in anger, and seriously mauled Prince of Wales.

 

Later Allied successes such as the eventual sinking of Scharnhorst, and at Leyte Gult, used radar rangefinding and direction to target the enemy ships, in a force 10 storm in the case of Scharnhorst, proper Gotterdammerung stuff...

 

I am sorry to hear that your father was taken aboard Altmark; a school friend's father was transferred to her when she refuelled Graf Spee.  He had nothing but praise for Langsdorf, Graf Spee's captain, and his crew, who had organised an xmas party for their 'guests', and told me that their treatment in the internment camp was, while not exactly fun, reasonable, and that they were given good rations even towards the end when this would not have been automatically assured in a collapsing Germany.  But his view of their treatment in Altmark, which seems to have been very much a Party ship in the not very pleasant sense of the word, was very different, and they'd had a pretty rough time of it from officers and crew.  Langsdorf was of course famously no Nazi, and his ship was scuttled flying the Imperial colours.

[chris p bacon]

1 hour ago, The Johnster said:

I am sorry to hear that your father was taken aboard Altmark; a school friend's father was transferred to her when she refuelled Graf Spee.  He had nothing but praise for Langsdorf, Graf Spee's captain, and his crew, who had organised an xmas party for their 'guests', and told me that their treatment in the internment camp was, while not exactly fun, reasonable

It was similar for Dad, The Altmark was awful and his (and other merchantmens)  treatment in France was terrible. After a camp inspection by Donitz he ordered the men to be taken into Germany where they set their own camp up at Marlag Und Milag Nord near Westertimken(?) Dad met and spoke to Donitz as he could speak some German, he said he was a pleasant chap and didn't come across as a Nazi party member.

[Kickstart]

7 hours ago, Tankerman said:

 

Concerning the range of conventional shells. The longest range hit on a ship from another ship is generally believed to be that obtained by HMS Warspite when one of her 15 inch shells hit the Italian battleship Giulio Cesare at a range of 26,000 yards, or approximately 15 statute miles, during the Battle of Calabria in 1940, when both ships were steaming at around 25 knots.  

 

The bit that amazes me is that even using the muzzle velocity (~2500 feet per second) that shell took 30 seconds to reach its target (reality is longer, with trajectory, velocity reducing with time , etc). Assuming 20 knots (quoted speed for the ship is 21.5 knots) for the Giulio Cesare it had moved ~330 yards in the time the shell was in the air. Ok, with one ship directly chasing the other targeting and predicting position is easier, but evasive action when a salvo is fired would result in the target being in a possibly significantly different place.

 

All the best

 

Katy

[Tankerman]

1 hour ago, Kickstart said:

The bit that amazes me is that even using the muzzle velocity (~2500 feet per second) that shell took 30 seconds to reach its target (reality is longer, with trajectory, velocity reducing with time , etc). Assuming 20 knots (quoted speed for the ship is 21.5 knots) for the Giulio Cesare it had moved ~330 yards in the time the shell was in the air. Ok, with one ship directly chasing the other targeting and predicting position is easier, but evasive action when a salvo is fired would result in the target being in a possibly significantly different place.

 

All the best

 

Katy

 

Hi Katy,

 

The speed of the Giulio Cesare was 21.5 knots as built, but she was extensively modernised in the 1930's, this included both new boilers and steam turbines, which raised her speed to over 25 knots. 

 

Warspite, and other major warships, were fitted with a device known as an Admiralty Fire Control Table. It was basically an analogue computer which provided the necessary readings of the elevation and deflection of the guns to ensure that the shells landed either at, or close to, the position of the enemy ship.

 

I have had an interest in the naval history of the first half of the twentieth century from a young age, one of my great uncles joined the RN in 1897 and served on various ships, including a Grand Fleet destroyer during WWI, until 1923 when he completed his 22 years service. The years from 1897 to 1901 didn't count towards his pension as he was classed as a boy seaman.

 

When I started my own apprenticeship as an electrician at Falmouth Docks in 1962 quite a few of the leckys had served in the RN either from before or during WWII, my obvious interest resulted in me being given a lot of information about the ships they served on.

 

[PenrithBeacon]

2 hours ago, Kickstart said:

The bit that amazes me is that even using the muzzle velocity (~2500 feet per second) that shell took 30 seconds to reach its target (reality is longer, with trajectory, velocity reducing with time , etc). Assuming 20 knots (quoted speed for the ship is 21.5 knots) for the Giulio Cesare it had moved ~330 yards in the time the shell was in the air. Ok, with one ship directly chasing the other targeting and predicting position is easier, but evasive action when a salvo is fired would result in the target being in a possibly significantly different place.

 

All the best

 

Katy

Presumably that shell was one of a salvo ? I gather, from naval history books, that Dreadnought battleships and their successors usually fired their main armament in salvos, the better to ensure a hit.

[t-b-g]

I have recently taken up an interest in the American Civil War and have been watching some battlefield walks/tours that have appeared on Youtube.

 

One of the Gettysburg guides has a lovely turn of phrase and when he was talking about a rather ineffective artillery barrage he came out with "Even a blind squirrel finds a nut sometimes" to describe the damage done. Firing at a mile or so range through thick smoke wasn't a good way to pick out targets accurately but every once in a while they scored a hit. One of the enemy cannons was knocked out of action by a shell going down the hole in the end of the barrel.

 

No doubt there is a degree of skill in hitting a moving ship from another moving ship at 15 miles range but with the technology of the day, I wouldn't like to say how much was skill and how much was fortune.

[Reorte]

8 minutes ago, t-b-g said:

No doubt there is a degree of skill in hitting a moving ship from another moving ship at 15 miles range but with the technology of the day, I wouldn't like to say how much was skill and how much was fortune.

I'd imagine fortunate was a big part of it but it's also true you make your own luck; could've just been very lucky but presumably a good crew could turn very little chance at all into low but plausible.

[t-b-g]

18 minutes ago, Reorte said:

I'd imagine fortunate was a big part of it but it's also true you make your own luck; could've just been very lucky but presumably a good crew could turn very little chance at all into low but plausible.

 

I always think that the skill is in getting the shell somewhere near the target. Whether it is a hit or a near miss is where the luck comes in. The more near misses you get, the greater the chance of getting a hit.

[The Stationmaster]

25 minutes ago, PenrithBeacon said:

Presumably that shell was one of a salvo ? I gather, from naval history books, that Dreadnought battleships and their successors usually fired their main armament in salvos, the better to ensure a hit.

I think the normal procedure was to go to broadsides once they had found the range but obviously you can't fire broadsides in a stern chase.

 

6 hours ago, The Johnster said:

The Germans had radar at least as highly developed as ours in the early years of the war, but their concept of what it was for was for directing naval guns rather than incoming aircraft.  Thus their gunnery was better than ours, as suggested by your father's experience on British Strength.  Bismark, as is well known, destroyed Hood with only the second shell she'd ever fired in anger, and seriously mauled Prince of Wales.

 

 

HMS Hood, like a number other British warships, was equipped with Type 284 gunnery radar for ranging her main armament and of course the two County class cruisers had shadowed Bismarck, before the engagement - and continued to do so after the sinking of the Hood - using Type 284 gunnery radar.  Hood also had Type 279 air warning radar.

 

According to a number of sources the shell which caused the magazine fire and consequent which sank the Hood was one in its fifth salvo fired at the Hood.