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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 16th, 2017, 9:30 pm
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General characteristics of the Forrest Adams and Charles Ogden classes as originally built
Type: Destroyer
Displacement: 2,616 tons standard; 3,460 tons full load
Length: 400 ft 4 in (122 m)
Beam: 40 ft 11 in (12.5 m)
Draft: 14.3 ft (4.4 m)
Propulsion: 10 General Motors/General Electric diesel electric generator complexes (6,100 HP ~4,550 kW each) for a total of 61,000 HP (45,500 kW)
2 shafts 60,000 shp
Speed: 37. knots (70 km/h)
Range: 4,500 nmi (8,300 km; 5,200 mi) at 20 knots (37 km/h; 23 mph)
Complement: 300 as designed
Armament:
Forrest Adams class as planned.
8 × 3.9 in (10 cm)/50 cal guns in four Mk 6 DP twin mounts (4 x 2)
8 × 1.18 in (3 cm) Winchester Mk 2AAA Gatling guns (8 x 1)
Up to 11 × 20 mm Hotchkiss cannons (pintle mounts)
2 × Depth charge racks (16 depth charges capacity each, no reloads) or
16 × K-gun depth charge throwers
10 × 21.67 in (55 cm) torpedo tubes (2 x 5) (2 sets of Mk 11 55/550 reload torpedoes)
Charles Ogden class as planned:
4 × 5.9 in (15 cm)/50 cal guns (in 2 × 2 Mk 3 DP mounts)
8 × 1,18 in (3 cm)/50 cal Winchester Mk 3 AAA Gatling guns (8 x 1)
2 × 6 barrel Mk 2 RBU 3000 ASW weapons (forecastle)
1 × Depth charge rack (16 depth charges capacity, no reloads, often landed)
16 × K-gun depth charge throwers with up to 80 depth charges (4 x 4)
Note: The Forrest Adams and Charles Ogden destroyer classes were attempts to build a true fleet destroyer as opposed to the WWI holdovers which were more like subchasers or overglorified torpedo boats than anything else.

FLUFF: TORPEDOES; ONE IF BY SHIP, TWO IF BY AIR; THREE IF BY SUB.

In the RTL 1920s if you are the newly minted MIT trained torpedo expert Ralph Waldo Christie you will have several choices in front of you as you enter the bewildering intensely politicized US government owned and operated torpedo designing and building operation on the aptly named Goat Island Torpedo Facility.

Well... not really. The USN had 40 solid years of torpedo design and construction and they thought they knew what they doing. Basically the RTL US Navy "appropriated" the engineering work that the E. W. Bliss Company of Brooklyn, New York company had done to create the American pattern wetheater bottled-air alcohol-fueled turbine powered torpedo. The RTL USN was not interested in reinventing a working wheel. They set Christie to work on an improved gyro guidance and on a magnetic influence feature to add to the Mk 5 exploder.

In the RTL, Christie screwed up the magnetic influence feature by not forcing the testing against live targets with live torpedoes. That was part of the politics within the US military establishment. The ice cream budget was more important to the depression era USN than the ordnance testing protocol. There were other things going wrong; that were not Christie's fault.

Anyway, the USN civil service engineers (flakes) at Goat Island had several bench projects going. One was a hydrogen peroxide oxidizer mod to the Mk 10 torpedo that promised to increase its range by a whopping 66%. Another was an electric torpedo, but both of these were backbenched for the Mk 13 (America's first purpose designed aerial delivered anti-ship torpedo), the Mk 14 submarine torpedo, and the Mk 15 destroyer torpedo. All of these torpedoes had operating characteristics that were wet heater alcohol fueled turbine motor based, and the ranges were deliberately designed not to exceed the average wander error estimated over run time to the target. In the case of the Mk 15 that meant about 5,500 meters at 23 m/s. and the result meant that the USN regarded anything beyond 500 seconds for their largest and longest running torpedo under development would be superfluous. So the proposed hydrogen peroxide (NAVOL) Mark 16 with 1000 seconds run time and an estimated reach of 10,000 + meters was not deemed cost effective.

Yeah. That was the RTL 1920s USN.

The Japanese put in the money and the time and created the Type 93. Twice the effective range of a bench model Mark 16 and 2000 seconds run time in an issued in quantity weapon by 1935!

The RTL USN from 1941 to 1947 caught flatfooted issued wartime emergency requirements and started development projects for 18 different types of torpedo. The CBASS Mark 48 is still living on the fruits of that panic research and development.

WHY? AND WHAT COULD BE DIFFERENT; IF ANYTHING?

The failure point came here. Functionally and in summary, Bliss had, up to this case, been in an ongoing and quite fruitful technology exchange with the Stabilimento tecnico Fiumano,Torpedofabrik Whitehead & Co., and
Royal Laboratories. E. W. Bliss Company was part of that international combine which exchanged information on any new innovation or tweak to the Whitehead Torpedo. The Whitehead still used a reciprocating engine propulsion system. The US company had worked out a solution to torpedo rollover which involved turbine technology. The US government classified it as a state secret. Bliss objected and the US government took over torpedo development as an owned public property. This was disastrous. See the cites above for why.

What can be done to undo the harm Woodrow Wilson's lawyers caused; is simple. Keep private industry in the design loop. American industry was a world leader in the following areas;

a. electromotive technology-especially battery storage demand draw propulsion systems.
b. internal combustion engines
c. laboratory testing of industrial products.
d. guidance systems and autopilotage.

These are exactly the specific areas in which USN civil service technicians in the torpedo development program failed. To make the fixes in the government products the USN had to turn over the problem to Harvard, RCA, Westinghouse, General Motors and a host of other companies, even some who made bathtubs and automobile headlamps.

E.W. Bliss in 1934 delivered a workable model of the Mk 13 torpedo. They made the first run of about 200 fish. These were used at Coral Sea with devastating effect. Then the USN took over production and that was the series of fish used at Midway and in the early Solomon Islands carrier battles. With well known disastrous results. Private industry with industrial product testing and captured German, Japanese and especially Italian technology fixed the Navy product, with a few American tweaks added. By the time of the Marianas Campaign, the Mark 13 was unrecognizable from the crummy weapon use at Midway. The Mark 13 failure was the most visible and the most urgently fixed. The naval aviators had admirals who were vocal and energetic. The submariners had Christie until Lockwood entered the fray.

THE FIX:

In the 1920s, despite the disadvantages of high maintenance loads, slow speeds and short range and large angle solution errors attendant to such torpedo characteristics compared to target ships, it is really obvious that unless the USN embraces the NAVOL torpedo (too expensive and outside the effective engagement parameters possible with American technology.) the electric torpedo is where the money should go. The reasoning is quite simple. bubbler (wetheater) torpedoes point back at the launching submarine ore destroyer. The motor noise involved makes the obvious acoustic seeker not viable with 1920's technology and the electric torpedo is simpler to make; especially for a US that has recent experience with electric propulsion for vehicles (US cities have electric trolley cars as mass transit in the 1920s, there's your 700 kWatt torpedo electric motor right there along with the batteries and the drives.)

Problems with depth setting, gyro control, warhead detonation and so forth still remain, but the propulsion is solvable. You cannot handwave itr away, but with fresh eyes (Westinghouse) the submarine torpedo is a doer by 1925.

HYPOTHETICAL RESULTS:

That blasted RTL US Naval Torpedo Factory 21.67 in Mark 20. Herein IDed as the Mark 11

Ship Class Used On:.................Submarines
Date Of Design:.......................1920-1930
Date In Service........................1931
Weight....................................2,866 lbs. (1,300 kg)
Overall Width/Length:...............21.67 in/18 ft (55/550 cm)
Explosive Charge......................585 lbs. (265 kg) HBX
Range / Speed..........................4,000 yards (3,650 m) / 31 knots /16 m/s
Power:....................................Electric-Battery, seawater
Guidance.................................Passive acoustic

21.67 in (55 cm) Mark 12

Ship Class Used On:.................Cruisers and destroyers
Date Of Design:.......................1919-1927
Date In Service........................1930
Weight....................................4,40- lbs. (2000 kg)
Overall Width/Length:...............21.67 in/24 5 in ft (55/750 cm)
Explosive Charge......................585 lbs. (265 kg) HBX
Range / Speed..........................8,000 yards (7,315 m) / 31 knots /16 m/s
Power:....................................Electric-Battery, seawater
Guidance.................................Passive acoustic

21.67 in (55 cm) Mark 13

Ship Class Used On...................Cruisers and destroyers
Date Of Design.........................1924
Date In Service........................1932
Weight....................................4,800 lbs. (2,177 kg)
Overall Length..........................24 ft 0 in (7.315 m)
Explosive Charge......................880 lbs. (399 kg) HBX
Range / Speed.........................18,000 yards (16,500 m) / 46 knots
Power......................................Hydrogen Peroxide (Navol) turbine
Guidance..................................Mark 12 Mod 3 gyro

21.67 in (55 cm) Mark 14

Ship Class Used On...................Aircraft
Date Of Design.........................1924
Date In Service.........................1930
Weight.....................................2,200 lbs. (1000 kg)
Overall Length..........................13 ft 5 in (4.089 m)
Explosive Charge.......................350 lbs. (159 kg) TPX
Range / Speed..........................6,300 yards (5,800 m) / 33.5 knots
Power......................................Electric battery, seawater
Guidance..................................Passive Acoustic

The fancy widgets in the magnetic influence feature may be nice to have, but an inertia hammer striker initiated detonator would be more useful.

Torpedoes that work from the start. Here is what could happen at the front end of a war.


Aircraft Carriers.............(4) SHINANO@, SHOKAKU, TAIHO, UNRYU All sunk after the torpedo crisis was resolved in 1943.
Escort Aircraft Carriers....(4) CHUYO, JINYO, OTAKA, UNYO Same again
Battleships....................(1) KONGO Same again
Heavy Cruisers..............(4) ATAGO, KAKO, MAYO, ASHIGARA# 3 sunk after 1943.
Light Cruisers................(9) AGANO, IZUZU, NAGARA, NATORI, OI, TATSUTA, TENRYU, YUBARI, and TAMA (in combination with aircraft) 7 sunk after the torpedo crisis.
Destroyers....................(38) (One sunk in combination with aircraft) 4/5 after the torpedo crisis
Submarines...................(23) Same as the destroyers.
Total.............................83

and as many again damaged.

From acorns grow oaks.


Last edited by Tobius on July 17th, 2017, 1:46 am, edited 4 times in total.

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acelanceloet
Post subject: Re: Mister Hoover's NavyPosted: July 16th, 2017, 9:48 pm
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Deck area is not the issue. the underwater volume of the ship is the same as the weight of the vessel (look up 'displacement' of a ship), which means you remove volume of the hull, you will have to remove weight as well.

While wetted surface area is one component of drag, it is at higher speed the one least important. increasing your wavemaking resistance for the sake of lowering wetted surface area is an tradeoff that will result in an lower top speed at the relative speeds we are talking about here. This is only worth it at speeds far below hull speed.

The diesel engines of the time were heavier then the steam plants of the same power. Using diesel power will, IIRC, result in lower speeds available on the same hull and armament. one big engine is also always more weight efficient then multiple smaller ones, so I highly doubt the issues I spoke of will be fixed by using a diesel electric powerplant as you describe.

The fubuki is actually in about the same armament weight range as your ship, slightly larger and slightly larger guns (note that guns tend to be a bit heavier then torpedo tubes)

anyways, your latest version is indeed a lot more like it ;)

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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 16th, 2017, 9:52 pm
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acelanceloet wrote: *
Deck area is not the issue. the underwater volume of the ship is the same as the weight of the vessel (look up 'displacement' of a ship), which means you remove volume of the hull, you will have to remove weight as well.
I understood that displacement is exactly what the word states, the weight of water moved aside that the ship rests on. The float bubble must exceed the displacement. The float bubble still does.
Quote:
While wetted surface area is one component of drag, it is at higher speed the one least important. increasing your wavemaking resistance for the sake of lowering wetted surface area is an tradeoff that will result in an lower top speed at the relative speeds we are talking about here. This is only worth it at speeds far below hull speed.
Hmm. That makes sense up to a certain limit. Area rule for ships?
Quote:
The diesel engines of the time were heavier then the steam plants of the same power. Using diesel power will, IIRC, result in lower speeds available on the same hull and armament. one big engine is also always more weight efficient then multiple smaller ones, so I highly doubt the issues I spoke of will be fixed by using a diesel electric powerplant as you describe.


The US Navy went out of their way to create lightweight diesels in the 1930s. They succeeded beyond their RTL expectations. (The failure being the HORS.) The steam plant by volume not only is the turbine assembly, it is the condensers and the circulators, and all the heat recovery ancillary systems that go with a steam turbine plant. That eats volume.

Another thing to consider is that ten small engine rooms can be placed more conveniently inside a hull than one big engine room. Redundancy, compartmentalization, distributed weight on the hull are advantages. (Diesels, as you said, are heavy, I discuss all of this under Mister McKinley's Navy) This is an electric propulsion system, not a direct drive geared one (The US had a lot of RTL trouble with both steam turbine construction and geared final drives, see above the torpedo discussion, wetheater vs. electric.). The ability to jack in power in increments of 10% is also a cost efficiency. Anyway, the advantages make warship if not commercial sense.
Quote:
The Fubuki is actually in about the same armament weight range as your ship, slightly larger and slightly larger guns (note that guns tend to be a bit heavier then torpedo tubes)


Empty torpedo tubes. the Fubukis carried 9 massive 61 cm bore torpedo tubes with torpedoes aboard and one complete set of reloads in below deck stowage.

The short destroyers I give you do not carry torpedo reloads.
Quote:
anyways, your latest version is indeed a lot more like it ;)
I thought you would like it. It was the original first version. I thought it was too big.


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acelanceloet
Post subject: Re: Mister Hoover's NavyPosted: July 16th, 2017, 10:41 pm
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Quote:
I understood that displacement is exactly what the word states, the weight of water moved aside that the ship rests on. The float bubble must exceed the displacement. The float bubble still does.
This is right, but the weight of the displaced water is also the same as the weight of the ship. So all weapons, stores, machinery and other things on board a ship together can be limited by volume and/or by weight: they might not be too heavy, and there must be space for them in or on the ship.
Quote:
Hmm. That makes sense up to a certain limit. Area rule for ships?
Area rule as used in aircraft, which I think you refer to, does not apply to ships because the speed of sound in water is higher while the speed of ships is lower then that of aircraft. The area rule applies when an object goes transsonic, so these rules do not apply.

The issue is that, if you keep a ship the same and increase the speed (for example 10% more, 1,1) , you can roughly say that wetted surface resistance goes up to 1,1 ^2 but the wavemaking resistance will go up with 1,1^4 (you can actually find this if you look up the formula's, but I will not go into that much detail here). this means that relatively, the wavemaking resistance goes up exponentially with the speed, and the higher the speed, the more of the total resistance will be the wavemaking resistance. These formulla's only apply to non-planing hulls and are only accurate below hull speed: above this speed the percentage taken by wavemaking resistance will actually be worse than I described.

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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 18th, 2017, 9:38 pm
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acelanceloet wrote: *
Quote:
I understood that displacement is exactly what the word states, the weight of water moved aside that the ship rests on. The float bubble must exceed the displacement. The float bubble still does.
This is right, but the weight of the displaced water is also the same as the weight of the ship. So all weapons, stores, machinery and other things on board a ship together can be limited by volume and/or by weight: they might not be too heavy, and there must be space for them in or on the ship.
I thought that even with the modifications I made (like halving storeables loads) that there was still enough float bubble to maintain buoyancy.
Quote:
Hmm. That makes sense up to a certain limit. Area rule for ships?
Here I think we wrote past each other. My fault it is for being unclear.
Quote:
Area rule as used in aircraft, which I think you refer to, does not apply to ships because the speed of sound in water is higher while the speed of ships is lower then that of aircraft. The area rule applies when an object goes transsonic, so these rules do not apply.

The issue is that, if you keep a ship the same and increase the speed (for example 10% more, 1,1) , you can roughly say that wetted surface resistance goes up to 1,1 ^2 but the wavemaking resistance will go up with 1,1^4 (you can actually find this if you look up the formula's, but I will not go into that much detail here). this means that relatively, the wavemaking resistance goes up exponentially with the speed, and the higher the speed, the more of the total resistance will be the wavemaking resistance. These formulla's only apply to non-planing hulls and are only accurate below hull speed: above this speed the percentage taken by wavemaking resistance will actually be worse than I described.
Area rule for aircraft is a fluid volume rule for aircraft. Many people assume that because the speed of sound is associated with the rule, that means it is different from the fluid area rule for ships. Actually both of these rules are displacement rules. As I understand it; the air pushed aside flows around an aircraft shape. Wings and control surfaces are part of that shape. The deviation from the ideal constant cross sectional area displacement of air introduces severe drag as the surface the air has to move around increases suddenly in area. To approximate the constant cross sectional area to minimize drag, the fuselage of a supersonic capable aircraft has its fuselage pinched in (the famous coke bottle) so that the sections of the plane where extrude the wings and control surfaces are presented roughly as a constant cross section area to windflow.

The area rule for ships originated as an attempt to keep a constant cross sectional volume for the float bubble over the length of the hull above the keel so that the ship's keel would not hog (curl up or sag (curl down) over length and the hull would not deform.

In wooden ships, there is such an absolute material limit as to how long the hull can be even with the area rule. (I think it is about 150 meters). Steel ships in theory could be about 10 X that length.

In any event, both rules in a fluid, as regards displacement (push aside through movement) work exactly the same fundamental way. You would see submarines assume the coke bottle shape at the control extrusions as soon as wetted surface impedence makes it necessary. Sound in air at 340 m/s creates the impedence wall where we have to coke bottle aircraft to pass through with efficiency. In water (as you know far better than I), sound travels ~ 1480 m/s, but we will find that severe drag will force us to coke bottle our subs when they operate at about the speed of a Shikval torpedo. (75-80 m/s)

We just do not notice the drag effect of water upon current ships more than we do because they are so slow. It would be as if we would face the area rule with dirigibles in the air if we had not learned how to fly instead. We would not see the need to use the area rule to fight drag until we approached ~ 100 m/s with a zeppelin; which is of course impossible with our current technology. In fact, from the structural point of view, though, the zeppelin (and the blimp) conform more to the floatation component of the cross sectional area rule as we currently use for ships moving through fluids. (water in this case) and when we started building them we used the area rule as we understood it from the shipwright's art.

And that (see above) is my understanding now. Thank you for that quite clear wave resistance explanation as to volume effect. Brute force it is for the short length destroyers, then. I'll go back and edit hp for it.

And now for those treaty cheater cruisers I promised.


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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 18th, 2017, 10:00 pm
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Nice pair of [cough] "8,500 long ton displacement" cruisers.


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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 18th, 2017, 10:04 pm
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AU ALTERNATIVES:

The USN, as a reminder, in the AU Washington Naval Treaty looks like this.

  • Tonnage limitations
    Country Capital ships Aircraft carriers
    British Empire 525,000 tons 135,000 tons
    (533,000 tonnes) (137,000 tonnes)

    United States 395,000 tons 270,000 tons
    (401,338 tonnes) (274,,333 tonnes)

    Empire of Japan 315,000 tons 81,000 tons
    (320,000 tonnes) (82,000 tonnes)

    France 175,000 tons 60,000 tons
    (178,000 tonnes) (61,000 tonnes)

    Germany 175,000 tons 60,000 tons
    (178,000 tonnes) (61,000 tonnes)

    Italy 175,000 tons 60,000 tons
    (178,000 tonnes) (61,000 tonnes)

That reduces the battle-line to 12 existing US battleships but allows the US to build up to 8 aircraft carriers. This includes 198,000 tons for the Lexingtons and allows 72,000 tons for the two additional carriers after the Lexington conversions enter service. The three converted "experimental" Derfflinger conversions are not counted toward the carrier tonnage. The British keep their four WW I curiosities and their Argus and Hermes are not counted toward their carrier tonnage, while the Japanese are allowed four new builds of their own and keep both the Hosho and the to be built Ryujo as their two "experimentals".

-------------------------------------------------------------------------

On the cruiser question, the USN may call their bodyguard ships "frigates" to distinguish these fleet attached units from the traditional "independent" cruisers, but the ships still count toward the cruiser tonnage totals. as amended in the 1930 London Conference.
  • Tonnage limitations
    Country Cruisers Destroyers
    British Empire 339,000 tons 235,000 tons
    (344,400 tonnes) (238,771 tonnes)

    United States 325,000 tons 270,000 tons
    (330,215 tonnes) (274,,333 tonnes)

    Empire of Japan 208,850 tons 151,000 tons
    (212,201 tonnes) (153,423 tonnes)

    France 135,000 tons 105,000 tons
    (137,166 tonnes) (106,695 tonnes)

    Germany 135,000 tons 105,000 tons
    (137,166 tonnes) (106,685 tonnes)

    Italy 135,000 tons 105,000 tons
    (137,166 tonnes) (106,695 tonnes)

None of the parties could agree on submarines, except that Germany pledged to have none and the Japanese demanded parity. In the end, a compromise was reached whereby signatories pledged not to exceed their destroyer tonnage allotment for the submarine tonnages they would build, but they, except Germany, could build whatever kinds of boats they desired. For France and Italy, this meant small submarines and lots of them. For Japan this meant a defacto limit of 100 boats, because nothing short of a U-cruiser could operate in the Pacific in that AU era. America had her own submarine tradition left over from Mister McKinley's Navy that would practically limit her to about the same number of boats as Japan. Both nations would cheat on this ill-defined area with mixed AU results. Japanese boats would be well-armed and of good quality, but not well used. American submarine boats would be like other American warships, about average in overall; quality with somewhat marginal weaponry in the beginning, but rapidly capable of good use once the bugs in the crews and the weaponry was shaken out.

FRIGATES:

A cruiser by any other name is still a cruiser, unless you designed it to not be a cruiser. The role of the Laredos is somewhat different from the RTL Omaha class they are intended to emulate.

Specifications for the Laredo Class
Type: Light cruiser
Displacement: 8,050 long tons (8,179 mt)
Length: 550 ft (167.64 m)
Beam: 59 ft 1 in (18.0 m)
Draft: 20 ft 0 in (6.10 m)
Installed power: 100,000 shp (74,570 kW)
Propulsion: 12 Manitowoc diesel electric generator sets. 8,333 hp (6,414 kW) ea.
Speed: 35 knots (65 km/h) on trials
Endurance: 9,000 nautical miles (17,000 km) at 10 knots (19 km/h)
Complement: 26 officers and 285 rates
Armament:
Laredo;
8 × 5.9 in (150 mm)/50 cal guns (4x2)
8 × 1.18 in (3 cm)/50 cal Winchester Gatling guns (8x1)
10 × 21.65 in (55 cm) torpedo tubes (2x5)
Lincolnton;
8 × 5.9 in (150 mm)/50 cal guns (4x2)
8 × 4 barrel 1.18 in (3 cm)/50 cal Remington 1q auto-cannon (8x4)
10 × 21.65 in (55 cm) torpedo tubes (2x5)
Lawrence:
10 × 5.9 in (150 mm)/50 cal guns (4x2)
8 × 4 barrel 1.18 in (3 cm)/50 cal Remington 1q auto-cannon (8x4)
10 × 21.65 in (55 cm) torpedo tubes (2x5)
Armor:
Deck: 1.57 in (4 cm)
Belt: 3 in (7.5 cm)
Aircraft carried: 1 catapult and 1 seaplane. for the Laredo and Lincolnton classes.

The Americans build 4 Laredos, 6 Lincolntons, and 10 Lawrences for half their eventual allotted 1931 London Conference Washington Treaty cruiser tonnage. They were authorized 18 "heavy cruisers" to the UK's 12 and Japan's 10; Germany's, France's, and Italy's 7 each. Obviously with 165,000 tons left, the Americans are not going to be able to build 18 of the 10,000 ton cruisers, light or heavy, if they do not cheat. Nevertheless they will try to build 18 and not cheat too much.

Here is what they did about it to get 18 heavy cruisers. (For pictures of the results see above.)

==================================================

General characteristics of the Sacramento Class (as built)
Class and type: Sacramento-class heavy cruiser
Displacement: 8,390 long tons (8,520 t) (standard) 10,490 long tons (10,660 t) (full load) (See note.)
Length:
555 ft 2 in (170 m)
Beam: 58 ft (17.7 m)
Draught: 16 ft 8 in (5.1 m)
Installed power: 12 Manitowoc/Westinghouse diesel electric generator complexes at 6,705 hp (5000 kW) each
80,460 shp (60,000 kW)
Propulsion: 4 × shafts; 4 × General Electric electric motors
Speed: 32 knots (59 km/h; 37 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 14 knots (26 km/h; 16 mph)
Complement: Peace 25 officers , 400 rates; War, 30 officers, 480 rates
Armament: 4 × twin 7.91 in (20 cm)/L50 BLNR naval rifles Mark 7 (4x2)
32 Remington 1.18 in (3 cm)/L50 Mark 1 Q AAA guns (8x4 quad mounts)
10 × triple 21.67 inch (55 cm) torpedo tubes (2x5) (no reloads)
16 K-gun depth charge throwers (4x4), 80 depth charges (5 patterns of 16 or 10 patterns of 8)
1 x 6 tube ASW mortar (forecastle mount)
Armor:
Waterline belt: 2.9 in (7.5 cm)
Deck: 1.8 in (4.0 cm)
Barbettes: 1 in (2.55 cm)
Gun houses: 1 in (2.55 cm)
Magazines: 2.9–5.9 in (7.5–150 mm)
Bulkheads: 4.373 in (11.0 cm)
Aircraft carried: 1 × seaplane
Aviation facilities: 1 × aircraft catapult

Notes: Called the Union Iron Works or West Coast cruisers, these warships were officially listed for the Washington Treaty cruiser clause as being of 8,500 tons in displacement. Stuffed with a full war complement of fuel, fools and flammables and with ½ fuel onboard as they should have been tested for compliance; the ships were closer to 11,000 tonnes standard than to 10,000 tonnes and would be 12,000 tonnes deep load.

General characteristics of the Tallahassee class (as built)
Class and type: Tallahassee-class heavy cruiser
Displacement: 8,120 long tons (8,250 t) (standard) 10,500 long tons (10,688.5 t) (full load)
Length:
548 ft 6 in (167 m)
Beam: 65 ft 3 (19.8 m)
Draught: 16 ft 5 in (5.0 m)
Installed power: 10 General Motors/Westinghouse diesel electric generator complexes at 8000 hp (5,965 kW) each
80,000 shp (59,650 kW)
Propulsion: 4 × shafts; 4 × General Electric electric motors
Speed: 32 knots (59 km/h; 37 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 14 knots (26 km/h; 16 mph)
Complement: Peace 25 officers 400 rates; War 32 officers, 500 rates (see note)
Armament: 3 × twin 7.91 in (20 cm)/L50 BLNR naval rifles Mark 7 (3x2)
2 x twin 3.9 in (10 cm)
8x1 Winchester 1.18 in (3 cm)/L50 Mark 3 AAA Gatling guns (8x1)
10 × triple 21.67 inch (55 cm) torpedo tubes (2x5) (two sets of reloads for 30 torpedoes carried.)
Armor:
Waterline belt: 2.9 in (75 mm)
Deck: 1.5 in (40 mm)
Barbettes: 1 in (25.5 mm)
Gun houses: 1 in (25.5 mm)
Magazines: 2.9–5.9 in (7.5–150 mm)
Bulkheads: 4.373 in (110 mm)
Aircraft carried: 1 × seaplane
Aviation facilities: 1 × aircraft catapult

Note: Called the Cramp ships or East Coast cruisers, partly because of the pun on William Cramp and Sons where they were built, and also because the crew spaces were extremely tight so that in wartime the 110 extra men actually had to hot-bunk or else sleep in hammocks rigged anywhere they could find room. These warships were officially listed for the Washington Treaty cruiser clause as being of 8,000 tons in displacement. Stuffed with a full war complement of fuel, fools and flammables and with ½ fuel onboard as they should have been tested for compliance; the ships were closer to 11,500 tonnes standard than to 10,000 tonnes and would be 13,000 tonnes deeply loaded.

For supposedly smaller ships, the Tallahassees actually displaced more than the Sacramentos.

MORE FLUFF: CHEATING ON THEIR OWN TREATY, DAMN IT.

The Americans got around the destroyer angle by building two sets of destroyers; slow ones for commerce protection (the "shorts" which could be used in a pinch as fleet escorts at a cost in tactical speed.) and fast ones intended for fleet work. (the "longs" which were intended for pacing with the carriers and battleships.) There was a ten knot average difference between the two types, but it was expected that commerce defense would play a major role in any future British-Japanese-American dustups so the two tier approach was used.

The cruiser question was more problematic and sticky for the Americans. The British had figured out that they would have tonnage for 40-45 cruisers. Japan could build ~ 22-24 cruisers under the Washington rules and the Americans could build between 33 and 36 cruisers, the British estimated. Britain was aligned with France in Europe so she had assured superiority in home waters over the next three European navies combined (Italy, Germany and Russia). The Indian Ocean was a defacto British lake, so she felt she could maintain the Empire in the region as long as she held the Suez Canal and the Anglo-Egyptian satrapy that went with it. It was once past Singapore that things became very dicey. The Americans were noxious, ambitious, and powerfully present in the Philippines and the South Chine Sea. They sort of regarded the Pacific Ocean the way the British of 1923 regarded the Indian Ocean. It, the Pacific, was their lake by right of conquest. The British had used the Japanese to pack off the imperial Russian navy. And though Admiralty House and Whitehall did not publicly declare it, they needed Japan more than ever to balance off the Yanks. The Americans were aware and they were privately diplomatically quite angry about it, especially their navy officials. Part of the diplomatic infighting at Washington and later at London during the naval disarmament conferences, was about the Anglo-Japanese alliance. Although she had privately assured the Americans that she would abrogate the Anglo-Japanese Treaty, the Yanks after reading Japanese crypto with regards to the Sempill Mission and his subsequent pass-ons to the Japanese, the Americans were not buying that ship's bill of British guff at all.

Whether RTL or in this AU, the Americans are going to build those 18 heavy cruisers. it is the how in the AU that I wondered about.

The RTL cruisers fitted an emerging independent mission doctrine that the American armored cruiser had originally been designed to undertake. Long range commerce raiding, show the flag, and added punch to the line of battle was the armored cruiser, the intended battlecruiser mission and now that both of those types were obsolete, it fell to the heavy cruiser. Since the Hawkins class were the initial definition of a heavy cruiser for the British and that was the agreed upper bound limit to which the Americans stipulated in the Washington NAval Treaty, that was the RTL initial set of conditions the USN set to overmatch.

In the AU, the problem is how to build 18 heavy cruisers within 165,000 tonnes. Something has to give. The RTL American heavy cruisers all had huge for their size aviation complements and had foresworn torpedoes to get those seaplanes and attendant cranes and catapults. This chews up deck space, and hull volume like you will believe, when you carry 3-4 aircraft. The Japanese treaty cheaters to match such an aviation detachment and gun-power and also keep their torpedoes could not do it under 12,000 tonnes. it just could not be done. They tried with the Mogamis. See how that turned out?

For this AU, I figured that with the Laredos, Lincolntons and Lawrences already sporting single seaplanes and single catapults, that it might as well become doctrine: that American cruisers carry 1 floatplane each, and that American cruisers operate together in pairs or groups of four. The aircraft can joint share missions that way. Since it was likely that it would be the Americans who hunted and the foreign enemy who raids and runs, this seems to me a logical starting point for what an American cruiser in this AU should look like.

She will be on the smaller side of things. The USN already starts with a cruiser tonnage shortfall. It should come as no AU surprise (since Mr. McKinley's Navy had such success with them.) that torpedoes will be part of the armament almost as important as the guns. As for the guns, I think that mutual interference in flight of three shell salvoes is so well established post WWI that given a druther, the cruiser designer would go for a twin turret if he can squeeze another one in instead of the 3x3 arrangement. AAA is starting to be a concern. Even by the RTL late 1920s, the British have at least provided a mixed battery of HA and MA guns to handle anti-aircraft duties. For the Sacramentos, the AAA guns will be the ubiquitous 3 cm Remington Mk 1q quad mounts. As for the main battery (4x2), it will be as close to the 8 inch bore gun limit as the AU USN can achieve.

The Sacramento class you see, is the result. No torpedo reloads of course, since her role is primarily as a flagship for a task group. The Union Iron Works and the Portland Navy Yard will build 10 of them. Over the course of time, experience leads to the landing of the almost useless torpedo battery and the addition of several 10 cm DP/ASh/AAA guns in the voided spaces to beef up her air defenses as her eventual role will be as a carrier task force screen flagship and a fighter intercept director. (That silly foretop house will finally have a purpose.)

The Tallahassee class will be more successful, I think in this AU. She has a good mix of guns and torpedoes on her rather light displacement. Six 7.9 inch guns may be a light battery for a heavy cruiser but HMS Exeter seemed to hit hard enough with hers. What she lacked was torpedoes and an adequate AAA battery. The Tallahassees have those features. These cruisers will be the better general purpose cruiser during the treaty years, with that more balanced armament among air, surface and underwater threats. Cramp and Sons and Bath Iron works are scheduled to make 10 of these, on the fiction that the 5 of them that come from the Portland Navy Yard are armed with the easily replaceable 15 cm bore/L45 Mark 2 guns are actually "light cruisers".


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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 19th, 2017, 1:13 am
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Lessons learned from the Sacramentos.


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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 19th, 2017, 5:44 am
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Revised the Type 171 sub again.


Last edited by Tobius on July 19th, 2017, 7:23 am, edited 3 times in total.

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Tobius
Post subject: Re: Mister Hoover's NavyPosted: July 19th, 2017, 6:06 am
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General characteristics of the Sacramento Class Rebuilds (the Vicksburgs)
Class and type: Sacramento-class heavy cruiser as rebuilt
Displacement: 8,500 long tons (8,636 t) (standard) 10,710 long tons (10,882 t) (full load) (See note.)
Length:
555 ft 2 in (170 m)
Beam: 58 ft (17.7 m)
Draught: 17 ft 1 in (5.2 m)
Installed power: 12 Manitowoc/Westinghouse diesel electric generator complexes at 6,705 hp (5000 kW) each
80,460 shp (60,000 kW)
Propulsion: 4 × shafts; 4 × General Electric electric motors
Speed: 32 knots (59 km/h; 37 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 14 knots (26 km/h; 16 mph)
Complement: Peace 25 officers , 400 rates; War, 35 officers, 425 rates
Armament: 4 × twin 7.91 in (20 cm)/L50 BLNR naval rifles Mark 7 (4x2)
4 x twin 3.9 in (10 cm)L 50 DP/ASh/AAA guns Mark 6 (4x2
8 Winchester 1.18 in (3 cm)/L50 Mark 3 AAA Gatling guns (8x1)
1 x 6 tube ASW mortar (forecastle mount)
Armor:
Waterline belt: 2.9 in (7.5 cm)
Deck: 1.8 in (4.0 cm)
Barbettes: 1 in (2.55 cm)
Gun houses: 1 in (2.55 cm)
Magazines: 2.9–5.9 in (7.5–150 mm)
Bulkheads: 4.373 in (11.0 cm)
Aircraft carried: 1 × seaplane
Aviation facilities: 1 × aircraft catapult
Note: Portland Naval Yard received the refit order almost as soon as the new cruisers joined the fleet. Torpedo tubes were landed and the amidships spaces were reworked to take four twin 10 cm Mark 6 DP guns, to confer a better high angle anti-aircraft defense and to improve close in defense against the new fast 600 tonne torpedo boats the IJN is rumored to build.

General characteristics of the Vicksburg Class (as built)
Class and type: Sacramento-class heavy cruiser (heavily modified)
Displacement: 8,410 long tons (8,545 t) (standard) 10,700 long tons (10,872 t) (full load) (See note.)
Length:
555 ft 2 in (170 m)
Beam: 58 ft (17.7 m)
Draught: 17 ft 4 in (5.3 m)
Installed power: 12 Manitowoc/Westinghouse diesel electric generator complexes at 6,705 hp (5000 kW) each
80,460 shp (60,000 kW)
Propulsion: 4 × shafts; 4 × General Electric electric motors
Speed: 32 knots (59 km/h; 37 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 14 knots (26 km/h; 16 mph)
Complement: Peace 25 officers , 400 rates; War, 30 officers, 480 rates
Armament: 4 × twin 7.91 in (20 cm)/L50 BLNR naval rifles Mark 7 (4x2)
4 x twin 3.9 in (10 cm)L 50 DP/ASh/AAA guns Mark 6 (4x2)
8 Winchester 1.18 in (3 cm)/L50 Mark 3 AAA Gatling guns (8x1)
5 × 21.67 inch (55 cm) torpedo tubes (1x5) (2 reloads for 15 torpedoes total.)
8 K-gun depth charge throwers (2x4), 80 depth charges (10 patterns of 8)
1 x 6 tube ASW mortar (forecastle mount)
Armor:
Waterline belt: 2.9 in (7.5 cm)
Deck: 1.8 in (4.0 cm)
Barbettes: 1 in (2.55 cm)
Gun houses: 1 in (2.55 cm)
Magazines: 2.9–5.9 in (7.5–150 mm)
Bulkheads: 4.373 in (11.0 cm)
Aircraft carried: 1 × seaplane
Aviation facilities: 1 × aircraft catapult
Note: When the Japanese gave notice that they would walk out of the 1930 London Naval conference, the plans for the revamped Sacramentos (the Gettysburgs) and additional Tallahassees proceed. Revised more efficient hull forms and layout allow for a half torpedo battery and some ASW weapons. The amidships spaces are framed from the keel up to take four twin 10 cm Mark 6 DP guns, to confer a high angle anti-aircraft defense and to improve close in defense against the new fast 600 tonne torpedo boats the IJN is rumored to build. Installation of an improved 5 blade screw design restores the 2 knot loss in speed that the deeper riding hull entails.

FLUFF AND STUFF: TACTICS AMONG THE BIHG THREE; TORPEDOES, GUNS, AND ADMIRALS OH MY!.

In the AU as it is in the RTL, the time period is 1931. This is not the era of the Type 93 oxygen torpedo or of the magnetic influence feature for the Japanese or the British. The British, Americans and Japanese all essentially have similar automobile torpedo capability. These have warheads of 150-250 kgs of explosive and speeds of 15-20 m/s and run times that vary from 500 to 750 seconds. Gyro angles can be set on the torpedoes, either by hand before launch (British) or by mechanical interface in the tube (Japanese) or electrically (Americans) for a straight out run and then turn to meet the target on its predicted intended motion. The AU Americans have a slight edge in that their primary torpedoes are electric and are not bubblers that leave wakes pointing back at their cruisers and destroyers which launched the fish. The Japanese have the fastest torpedoes and the ones with the biggest warheads so in a melee surface battle their fish will be deadly at close range. The British have the mechanically most reliable and they are a fleet with the most recent battle experience, so those qualities are their advantages.

What goes for torpedoes, runs generally true for naval artillery with these AU points to be remembered. The British have a bewildering array of artillery throughout their fleet with 3 in, 4 in, 4.7 in, 5 in, 6 in, 7.5 in 8 in, 13.5 in 15 in and 16 in guns in the naval rifle inventory. For AAA guns, the RN uses a rather standard set of 2 pounder Vickers RFGs (4 cm/L45 or L60) for close in work and relies on the 4 inch/L45 gun in a 2 dimensional high angle mount Fire directors are optical based sights with mechanical clock target lead assist in local control. The British are the inventors of the central fire director method (1895, Fisher) and their current system is the Dreyer Table of WW I Jutland infamy. At Jutland, depending on the ship's crews using it, the Dreyer Table was either a superb aid, or it was terrible. Rangefinders and human errors brought on by excited British eyes peering through those fogged up stereo-coincidence rangefinders do not help with this system, when the tracking party tries to crank out a predicted motion and a range solution. Postwar after Beatty is quietly shunted aside, the British attend to the problems and train hard, so that by 1931, it is safe to assume that British Royal Navy gunnery is the benchmark in Europe.

The Japanese have never had trouble with gunnery. Their naval gun technology initially is French. and with it comes the French attitude towards training by the numbers so that a gun crew is accurate in its shooting The lesson Emile Bertin pounds that lesson into their novice naval officers skulls that the ship that hits first is usually the one that will survive.

The British come along and the Japanese learn from them; the tactics of the line, how to enfilade an enemy fleet under steam and how to use fleet scouts, how to signal maneuvers and an admiral's intent and use the torpedo in a gun action to drive an enemy into a kill box solution. It is British tactics with a Japanese twist that decides Tsushima. No-one should be ignorant of how much the Fighting Instructions influenced Togo. Or these guys:

Combined Fleet officers in tactical command
Admiral Naomi Taniguchi: 10 December 1928 until 11 November 1929
Vice Admiral Eisuke Yamamoto: 11 November 1929 until 1 December 1931
Vice Admiral Seizō Kobayashi: 1 December 1931 until 15 November 1933
Vice Admiral Nobumasa Suetsugu: 15 November 1933 until 15 November 1934
Vice Admiral Sankichi Takahashi: 15 November 1934 until 1 December 1936

Combined Fleet chiefs of staff
Rear Admiral Eijiro Hamano: December 1927 until 10 December 1928
Rear Admiral Ken Terajima: 10 December 1928 until 30 October 1929
Rear Admiral Koichi Shiozawa: 30 October 1929 until 1 December 1930
Rear Admiral Shigetarō Shimada: 1 December 1930 until 1 December 1931
Rear Admiral Zengo Yoshida: 1 December 1931 until 15 September 1933

It is not until 1935 when Yamamoto and his young samurai come into main influence that the battleship faction (戦艦派) yield prime place to the aircraft carrier faction (空母派). The Japanese submariners never have a say at all.

For the Americans, it is Riley stuck in the middle in the RTL. From the strategic and operational art perspective, (though I am an American, I can still be objective about this subject.) I doubt that there existed a finer officer corps on Earth for professional vision and for putting in the hard work to prepare a service for the war it was going to fight than the leadership of the United States Navy. When by 1925, the admirals commanding knew exactly what islands to hit and within 10% what forces would be needed for that Central Pacific Campaign, task by task, and objective by objective, right down to how many months it would take the fleet to work its way forward to a blockade position off Japan; then that is good strategic planning and operational art cognition.

But then there is the tactical element. In the RTL, replaying Jutland 5 times with aircraft carriers used in lieu of battlecruisers during the main fleet-exs of the era does not get the Yankee Navy ready for the Java Sea or Ironbottom Sound. The British Royal Navy admiralty may be terrible at strategic thinking and not have a clue about grand strategy, but scratch a British senior cruiser squadron captain or destroyer flotilla commodore and that man knows how to trap a raider or protect a convoy, or fight a night surface battle. British admirals, after the RN's dross performance of WWI, practice fleet evolutions until they can deliver a Teleuda or Cape Matapan in their sleep. As
goes the leadership, it trickles down to the rates. Plan a naval campaign? Nope. But fight a naval action? The British are good at it. The British taught the Japanese how to do it. The Japanese, being good students, in the RTL will surpass the teachers. So the RTL British navy will learn to their rue. But not only do the Japanese bring British tactical skill to the naval art; they bring American strategic planning acumen as well. At least until the Americans take the initiative away from them. Then all the Japanese can do is react. They still RTL will teach the Americans tactics down to the bitter end, but as astute as the Japanese navy is, it will never find the proper strategic solution to Plan Orange.

I cannot have a realistic AU, if I ignore those factors above. I can move some of the nascent trends I emphasized in Mr. McKinley's Navy forward to tweak the Yankee navy for Mister Hoover. For example, the love affair with mechanical fire control and gadgetry which Admiral Dewey's fleet has will not just be applied to ship's systems, but will find its way into the teeth this navy has. The guns will have ammunition that will perform to specs (No 1.1 inch shells backblasting AAA gunners as soon as the shells leave the gun's muzzles. And no torpedo crisis.) And the fleet will be battle-trained at least to French standards in battle drills. Better to have a severely undermanned; but well-trained fleet with working weapons than a fully manned fleet with half-trained sailors in marginal ships with defective weapons. The USN in the RTL is the least combat ready fleet among the big three when war comes to it, It still will be in this AU, but the small changes I present here so far and will introduce further, is a butterfly effect that should yield startling results.

By the way, who are the Americans in this gedankenexperiment?

US fleet commanders.

Henry A. Wiley: 1927–1929
William V. Pratt: 1929–1930
Jehu V. Chase 17: September 1930 – 15 September 1931
Frank H. Schofield: 1931–1932
Richard H. Leigh: 1932–33
David F. Sellers: 10 June 1933 – 18 June 1934

As a general rule, during this era, these men outranked their Japanese counterparts by a full grade. (Admiral), but this is a time in service brevet rank held during the command period and is not assumed to be a permanent rank unless conferred so by Congress. Upon retirement or being fired, (Admiral Kimmel comes to mind), the officer reverts to his previous permanent rank, usually that as a rear admiral.

The British leaders in this time usually depend on where the prospective war takes place. There are two Mediterranean commands, the Indian Ocean command, Home Fleet, and of course the China station. As far as I can tell, they are competent, if unimaginative. None of them are going to be a Richard H. Leigh or a Seizō Kobayashi, that is either luckless or a complete political imbecile.


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