5.25-inch Mk III - sketch design of mounting with telescopic hoists

5.25-inch Mark III mountings, Elswick Works, Newcastle-upon-Tyne, 26th October, 1948

Drawing No. 42294 (horizontal stowage)
Drawing No. 46006 (vertical stowage)
Drawing No. 42292 (articulated telescopic pusher hoist)

Top/Plan view (42294)

Elevation: 90°
Depression: 10°
Diameter Roller Path: 19’-0”
Rate of Fire: 48 rounds/minute H.A.
Rate of Fire: 24 rounds/minute L.A.
Weight of Oscillating Parts (2 guns): 25 tons
Weight of Turntable Structure etc.: 40 tons
Weight of Hoists: 18 tons
Weight of Gunshield (½”): 13 tons
Total Revolving Weight: 120 tons

Weight of Magazine Machinery: (H: 40 tons / V: 30 tons)
Weight of H.A. rounds in magazine: (H: 51.5 tons - 750 / V: 43 tons - 628)
Weight of L.A. rounds in magazine: (H: 8.25 tons - 120 / V: 6.33 tons - 92)

Each gun has 2 HA hoists and 1 LA hoist attached from the upper point to the cradle and the lower portion swings about a common trunnion at the base of the mounting structure.

Side view (42294)

Data taken from table of mounting sizes and table of powers

Protection of Battleships against underwater attacks

On the 5th of June 1914 sir Percy Scott wrote in The Times that battleships had become completely powerless against the submarine. On the 7th to 10th July three naval societies met at Newcastle. The Institution of Naval Architects, the Institution of Engineers and Shipbuilders of Scotland and North-East Coast Institution of Engineers and Shipbuilders.

Here, professor John Biles shared his studies on the underwater protection of battleships. He provided three designs with 100 mm armoured plates below the water line.

 

Design 1 (Revista de Marina)

The first two have the same armament: 6 guns of 356 mm in twin turrets and 16 guns of 152 mm. However, the former has a displacement of 13.000 tons and speed of 10 knots at a length of 102 metres between perpendiculars with a draft of 6 metres. The other design displaced 16.000 tons and had a speed of 18 knots at a length of 132 metres, beam of 24 metres and draft of 7 metres.

The first is in general better protected than the second. 250 mm belt against 125. Upper belt of 75 against 125, turrets of 300 against 125. 56 for both casemates.

The third project is closer to current battleships. Displacement of 28.500 tons, 21 knots speed, armament of 10 guns 356 mm and 16 of 152. Length between perpendiculars of 174 metres, 28 metre beam, 8 metre 70 draft. Armour 250 mm at the belt, 180 and 125 above, 300 turrets, casemates of 50 and deck 75 mm.

In closing he asked the questions:
1: If an armour of 100 mm below the waterline is sufficient against torpedoes in order to adopt on dreadnoughts of the latest type.
2: If the threat of submarines is great enough to warrant the adoption of this armour.
3: If the submarine is a great enough threat to implement this armour and the introduction of slow, small battleships of around 16.000 tons displacement and 6 main guns instead of 8 or 10.
4: If the system of armouring the bottom of ships has enough merit to justify the adoption of a ship form with greater resistance than the ordinary form.

 

Design 1 (Le Génie civil)

Design 1:

Length O.A.: 358 feet
Length P.P.: 336 feet
Maximum Beam: 80 feet
Draft: 20 feet
Displacement: 13.000 tons
Speed: 10 knots
Armaments: 6 of 14 inch, 16 of 5 inch

Belt: 10 inch
Upper belt: 3 inch
Under belt: 4 inch
Casemates: 2 inch
Barbettes: 12 inch
Deck: 2 inch

Design 2 (Le Génie civil)

Design 2:

Length O.A.: 460 feet
Length P.P.: 434 feet
Maximum Beam: 80 feet
Draft: 24 feet
Displacement: 16.000 tons
Speed: 18 knots
Armaments: 6 of 14 inch, 16 of 5 inch

Belt: 5 inch
Upper belt: 5 inch
Under belt: 4 inch
Casemates: 2 inch
Barbettes: 5 inch
Deck: 2 inch

 

Design 2 (Revista de Marina)

Design 3:

Length O.A.: 600 feet
Length P.P.: 570 feet
Maximum Beam: 91 feet
Draft: 28 feet 6 inch
Displacement: 28.500 tons
Speed: 21 knots
Armaments: 10 of 14 inch, 16 of 6 inch

Belt: 10 inch
Upper belt: 7 inch
Under belt: 4 inch
Casemates: 2 inch
Barbettes: 12 inch
Deck: 3 inch

Note:
The French article notes a 6-inch secondary battery, whereas the Spanish article notes a 5-inch secondary battery.

Many thanks to Coldown for his contribution. For more of his work, please visit the Spanish blog Reporte de Batalla at:
https://reportedebatalla.wordpress.com/

Sources:
Revista de Marina, 1915, Volume 60 Number 348, pages 31 and further.
Le Génie civil, 34rd Year, Tome 65 Numero 16, page 312 and further. (Number 1679 Saturday 15 August 1914)

5¼-inch pair H.A./L.A. mounting (hand loading at gun)

5¼-inch pair H.A./L.A. mounting (hand loading at gun)

Elswick Works, Newcastle-on-Tyne, 12th of July 1946

The amount of ammunition contained in the revolving rings, hoists and loading trays is such as to enable each gun to fire a total of 22 rounds at 16 rounds per minute (32 from the turret). Concurrate replenishment could be carried out at this approximate rate.

Each gun has one HA hoist, one LA hoist and one cartridge hoist. Ammunition is loaded from into the tray by hand and subsequent operations of setting the fuze (by Molins or similar type) and loading the gun will be carried out automatically. A compartment of spent cases is provided beneath the guns.

All the machines of the mounting will be hydraulically operated, the elevating and training operations being under the control of the E.M.V. R.P.40 system.

 

(Drawing No. N.44273, side view)

 

 

(front view)

Source:
DS.VA/6/25/15/14

Plan S

The following is a translated summary of a Dutch book from around 1937.

The author noted that the defence is a task of everyone. And that in the past naval officers debated in the open. This didn’t convince anyone, but gave detractors fuel for their arguments. Fortunately this practice has almost ended. But sadly those that don’t let themselves be heard get suppressed. That’s why we want a fleetplan from the navy. But the navy doesn’t come with one. Why?
    The navy has since 1813 needed to ask, not demand - answering to a minister of the navy that as chief of personnel never been further than a desk. They only ask for what 100% would be supplied. At all but one point in the many years has the position been taken by someone outside of the navy. At the moment, when we expect extensive propaganda, we see very little. Only in a “Onze Vloot” do we see that with due haste we need to expand our baseline, lest we no longer need to worry about the colonial budget. Yet, with the threat so great, where is the fleetplan?
    It is often thought that only expanding the army can suffice for defence plans. An understandable sentiment when looking at our eastern neighbours. One thinks of acquiring a few artillery pieces, but then forget that thousands and thousands of items that need to be supplied overseas.

A country needs to supply its resources. All the more in wartime. Even the US, with all its vast resources, noted 21 types of resources which they absolutely need for warfare. Without a naval force, Jhr Schorer notes, we get immediately choked. Two things are certain. We won’t start looking for fights. And it’s inconceivable the whole world turns on us. Possibly, nobody comes to our aid. But even in the worst case not everyone will be enemies. And we need to prepare for such eventually. To escort our convoys, we need 5 cruisers of around 15.000 tons with a cadre of smaller material.

The East Indies consist of densely populated areas but also sparsely populated areas, which without supply lines are incapable of stationing a modern army. Only territorial defence is possible in some of these regions. The best defence has always been the offence. It is unthinkable to let the enemy unleash its horrors upon our own territory. For this a mobile fulcrum is needed to support aggressive actions. Hence why 5 battleships are needed. 5 because there will always be one in maintenance and four makes a squadron.

Without any battleships, the enemy can rest easy in their attack knowing we have none. But with a battleship, we can with a single hit incur such damage that is fatal for an enemy far from home. Peculiarly, battleships are the cheapest. Airplanes have a life expectancy of hours, battleships of years.
    Furthermore, only the battleship can effectively fight other battleships. To destroy one battleship, the enemy has to send two. To destroy the squadron of Spee at the start of the war the allies had to send no less than 30 ships, a 6 fold force majeur. Fortunately, the Dutch shipbuilding industry is sufficiently equipped to lay down 3 battleships at the time

The empire of the Netherlands is a giant ABC-triangle. Amsterdam, Batavia, Curaçao. The communication between those needs to be maintained. To this end in peacetime there needs to be a force that can protect the waters of west indies and convoy the connection lines to the rest. Currently the west is unprotected as an apple ripe for the taking. Considering they participate in spending on our defence is it not fair for them to be protected as well? There needs to be a permanent squadron of 4 cruisers of 10.000 tons. Of course with 1 reserve ship and cadring of ten destroyers and primarily submarines and airplanes.
The primary task is protection of the west indies against foreign attacks and secondarily it must protect the merchant traffic between the Netherlands and Netherlands-Indies through the Cape of Good Hope, Cape Horn and Panama Channel. One has to remember a large portion of resources has to come from the Americas, such as Manganese ore.

Summarising:
5 battleships (4 + 1 reserve)
5 cruisers 15.000 tons (4 + 1 reserve)
15 cruisers 10.000 tons or less (12 + 3 reserve)
40 destroyers (32 + 8 reserve)
40 submarines (32 + 8 reserve)
And the needed small material, minelayers, minesweepers, repair ships, motor torpedo boats and no aircraft carriers.

Accounted for every battleship are 2 covering cruisers and 4 destroyers. Everyone knows this is too little, so we’re not trying to be a big naval power. For each heavy cruiser there are 2 destroyers per ship. Furthermore, 40 submarines, the weapon of the weak, are sufficient. To those that wonder why not go for an entirely submarine based fleet, if the submarines are the weapon of the weak? To those I have to explain that no one weapon is a panacea to everything. Secondly, only the battleship has a preventive function.

For the main base in the Netherlands, Den Helder is the prime candidate due to its position and history. The only detriment is communication with the hinterlands, which can be remedied with a good road network. For the East Indies, neither Tandjong Priok nor Soerabaja pose a great location. An ideal base would be difficult, but possible. For the West Indies, no matter how well fortified the islands are made, they can be surrounded and thanks to their size then form a detriment. The best option is a base in Suriname.

S., Nederland=Zeemogenheid, ca. 1937

5.25-inch Mark III star

As a successor to the 5.25-inch RP 10 Mk I and Mk II mountings the Royal Navy intended to develop the RP 40 Mark III mounting otherwise known as the 5.25-inch 80° Electrical Hydraulic T.959. However, this project shall not be the highlight for now. Instead, I will focus on a tangential project. On the basis of replacing the hydraulic 4.5-inch Mark VI rammer and substituting it by metadyne both for elevation and ramming, an all-electric mount was conceived. This would be the 5.25-inch RP 50 Mark III star mounting otherwise known as the 5.25-inch 80° All Electric T.960 produced by Vickers-Armstrong Limited and Messrs Metropolitan-Vickers Electrical Co. Limited

Design history

Of primary importance would be compatibility of the Mk III* mounting with the Mk III. Double deck loading, with shells and casings being on different levels would be employed and the distance between the underside of rollers and upper side of the coordinate deck would be 16 feet. The guns would be 7 in 6 ft apart. The training and elevation speeds ought to have been 20° per second maximum and acceleration of 10° per second per second. 

Supply of shell and cordite to the mounting was done by rotating shell and cartridge rings. These had a designed constant speed of 5° per second. The hoists consisted of two shell and one cordite hoist per gun and were either mechanically or electrically controlled by metadyne control. One of the shell hoists per pair would be provided with a fuze setter (Mk VII) as in the 4.5-inch Mk VI. Transfer to the loading tray is by hand and the chain type rammer is metadyne controlled.

A rate of fire of 16 rounds per minute with fuse setting could be achieved, or without fuse, or with 711 fuse, a rate of fire of 20 rounds per minute should have been obtainable.

The final time chart would not be ready, but the following estimates were provided.

Loading and gun rammer
0.30 seconds Press knob to release fuze setter head
1.40 seconds Lift shell from hoist into the tray
0.30 seconds Press knob to ram
0.50 seconds Ram
0.25 seconds Close breech
0.60 seconds Withdraw

Shell and Cartridge hoists
1.55 seconds Raise
1.30 seconds Lower

Particulars of rough design, 29th June, 1944:
Weight of shell: 80 lbs
No. of shells in one lift: 4
Length of lift: 50.5”

Weight of cordite case: 41 lb
No. of cases in one lift: 5
Length of lift: 52”

Weight of revolving structure: 100 tons
Weight of oscillating mass: 11 tons
Training ° per second: 20° per sec
Acceleration: 10° per sec²
Elevation ° per second: 20° per sec
Acceleration: 10° per sec²

On the 4th of July the revolving structure estimate increased to 105 tons (with a ½ inch shield). On the 7th the same month, the elevation acceleration was increased to 15° per sec². 6 Metadyne sets would be used. 1 - training set, 2 - twin sets combining shell and cordite hoists (one for each gun), 2 - twin sets for combining rammer and elevating drives (one for each gun) and 1 twin set for fuze setters. A local position was provided with joystick control.

 

5.25" Mark III*, electric mounting DrgNo. N34030

The shell ring would weigh 8500 lb loaded (of which 5200 lb would make up the 64 shells) and the cordite ring 4700 lb respectively with 32 shells of 1280 lb.
The elevation motor had shown a maximum performance of 20°per sec and acceleration of 21° per sec². The revolving weight of 105 tons had a 8.15 ft radius of gyration and out of balance of 3.8 inches. Oscillating weight was 11 tons per gun with 5.375 ft radius of gyration. The maximum power of the metadyne motors was 156 HP for training and 12 HP for elevation.

A mock-up of the hoist was to be prepared. A trial rammer with 4.5-inch Mk VI cradle would be prepared. Proposed trials for the system were one for full load, one for endurance, one for failure of power, one for failure of interlocks and a compatibility test. It was however not seen fruitful to do an endurance test due to the mock-up nature, but the other were approved and would be carried out.

Meanwhile, the admiralty had already shown very little attention for this project which has caused numerous delays. It now had started to doubt the merits of a vertical hoist arrangement and suspended works on the Mk III and Mk III* except for the hoist. 

On the 11th December 1946 the trials with the mock up would take place. However, the day prior an unfortunate accident took place. Immediate repairs were effected but only the hoist could be made operational. The loading tray had to be manually operated for the trial, at which a speed of 16 rounds per minute was achieved.

Not satisfied with this result, a number of adjustments were contemplated. The next month a test rate of 25 rounds per minute was achieved and the following month 30 rounds per minute. A new trial was planned but due to power outages at the factory this had to be postponed. By the 4th of March they had successfully trialled a delivery rate of 31 rounds per minute. This would unfortunately prove to be the last test and the mount was dismantled by the 9th of June before its last pre-disposal inspection.

Many thanks to Trainspite for his assistance in collecting the information to write this article. 

(Edit: Sources are from Tyne and Wear archives, DS.VA/6/25/11 and DS.VA/6/36/14/2)

Dutch planned acquisition of capital ships

There's a common saying on the internet - that the Dutch caused the start of both world wars by trying to order capital ships.

Today I would like to highlight 2 relatively unknown stories relavant in some form. I think it's safe to say most people know about the Battleship that were designed and proposed before World War One - as well as the Battlecruisers right before the German invasion. But there's 2 more cases.

The first happens before World War Two starts, namely before the Phoney War. In April 1939 minister Colijn contacted the 'British Envoy Extraordinary and Minister Plenipotentiary' Sir George Nevile Maltby Bland for the acquisition of 3 Battleships, which he could pay for in hard cash. Colijn judged the construction of Battleships too slow and wanted them as soon as possible. No ships in particular were mentioned, but it is speculated he thought of the R-class battleships or the Queen-Elizabeth class. The admiralty rejected the offer on 26th June 1939.

Another case happened during the war, but before the Japan entered. In 1940 A.J. Bussemaker and engineer H. Egeter proposed an emergency fleet plan that consisted of acquiring the US Battleships New York and Texas. Excluding some other measures to increase personell for the navy, they proposal included the removal of one twin turret from each ship and eight of the 12,7cm cannons. This would reduce the required crew complement from 1250 to 1000 men. The main battery turrets could be used to cover the Westervaarwater (Soerabaja) and the secondaries could cover a 'drastic need' of 12,7cm ordnance.

Sources:
Loderichs, Britse slagschepen voor de Koninklijke Marine, Marineblad 2020
Bosscher, De Koninklijke Marine in de Tweede Wereldoorlog, part two pg. 152
Bussemaker, H.Th., Paradise in Peril. Western colonial power and Japanese expansion in Sout-East
Asia, 1905-1941, 2001, pg 227

Update

Greetings everyone,

I hope you enjoyed the April Fools article. After reading Hoffmann's work I have been expressing my artistic tendencies by designing some ships. Creating these was a nice pastime that helped me appreciate the processes that went into designing ships.

In any case, I would like to take this moment to talk about the state of the blog. So far I've been posting multiple articles every Friday. This was never my original plan, I just felt like waiting a week after every post and thus I accidentally formed a schedule. I may stick to this for now, but I probably won't upload multiple posts nor every week as often as before. The reason for this is that I originally tried to rush some content on the blog first; so newcomers wouldn't find it empty if they wanted to read more. I still have plenty of potential content down the pipeline, but I am not yet sure if they fit the scope I'm looking for. Mayhaps that means I'll have to settle for shorter or more 'raw' content.

Regarding the content that I have put out so far, I can't say that I am as enthoustiastic as I had conceived. Since most of it is translating and summarising it doesn't feel as my own labour. Instead I feel like a cheap imposter. I guess it's not far from the truth. Afterall that's just the nature of digging through archives and libraries, but it feels disheartening to think of it this way. I just wanted to get that off my chest.

Anyways, expect less frequent content, meanwhile I will try my best to maintain or improve the quality. Untill then.

Yours truly,

Sanglune