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bezobrazov
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 13th, 2011, 2:05 am
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Between Jan. 1921 and Feb. 1924, a Royal Hellenic Naval Mission visited Washington, at the behest of the Hellenic Navy Minister, Vice-Adm. Stephanos Stephanopoulos-Comnenou, in order to examine and evaluate the right kind of vessels suitable for the RHN: s future needs. Also, at stake, was the outcome of the ongoing treaty negotiations between the Great Powers, the purpose of which was a general naval reduction after the outcome of the Great War, and how it might affect the structure and future size of the RHN.

Various suggestions were presented before the Mission, which was led by the respected and able Rear-Adm. Konstantinos Mavromichalis. The RHN: s Chief Engineering Officer, Lt. Com. Andreas Milas was also present. The Chief Naval Constructor, Rear-Adm. Giorgios Kontostephaniotes had taken ill and was bedridden, but close contact was nevertheless maintained to find out his opinions.

Commander William S. Pye, of the OpNav introduced the Greek Admiral to Capt. Stocker of Preliminary Design of the USN. This was an extraordinary step, reflecting the outgoing Wilson Administration’s desire to maintain friendly and supportive relations with the Hellenes; especially since more and disturbing details had reached the US capital about Osmanli (Turkish) atrocities committed during the Great War, but also being committed during the Third Greek-Turkish War raging during the Mission’s visit. (The Americans chose to, conveniently overlook, or ignore accusations against the Hellenic forces for the same crimes!)
The overall purpose of the Naval Mission was to look into an effective replacement for the ageing battleships of the RHN, units, that in previous conflicts had proved themselves only of moderate usefulness and limited success. The new evolution of the cruisers generally, and, in particular, the new type of ‘armored cruiser’ as envisaged in the British Hawkins-class promised well for the possibility of replacing the obsolescent vessels with new, more effective, and economical units.
Several designs for cruisers were looked at but rejected. The US Navy was in the same conundrum as the RHN, searching for the ideal future warship with which to maintain superiority against its enemies.

Capt. Stocker was a great proponent of the virtue of speed. He proposed, in March 1921, an 11,250 ton scout cruiser design capable of making 34 knots and armed with six 8” guns in three twins. The hull was to be unusually long at 625 ft, to fit the powerful machinery developing 61,000 EHP.
The problem was that this was only on a preliminary design stage and there were, as of that date no ready 8” guns. Besides, all 8” guns had been earmarked by the USN already for future use.
The design was cordially rejected.

Then, on Dec. 1, 1923, after two years of fruitless negotiations and search, Commander Henry S. Howard, attached to the Cruiser Design Team of the C&R, rang up the Hellenic Naval Attaché in Washington, Capt. Tassos Ypsilantis and told him that he had prepared a design that might interest the RHN. A meeting was set at Waldorf-Astoria, New York, on Dec. 22 between the Commander and Rear-Adm. Mavromichalis accompanied by Lt. Com. Milas. Capt. Ypsilantis acted as an intermediary.

The design thus presented before the Greek guests showed an 11,500 ton vessel, 634 ft long and armed with 12-8” guns in four triple gun houses. The speed was calculated at 34 knots also with 112,500 SHP. The Mission was interested and established further contact . Adm. Mavromichalis returned to the newly appointed capital of Constantinople in Feb. 1924, leaving Milas behind with full authority to tweak the design to suit Hellenic requirements.
Again, the lack of a ready 8” gun almost foundered the project. But Milas remembered the newly completed Kriti-class, and before the Kriti left Philadelphia for her voyage to Greece, Milas inspected her and, especially her Vickers-made 7, 5” guns. He found these suitable and requested Commander Howard to exchange the 8” to the existing 7, 5” type. Howard enlisted Capt. Train of BuOrd to find a new solution. The new preliminary design showed a substantial weight gain compared with the original design. Instead of the estimated 780 tons the battery, still a 12-gun configuration, weighed 745 tons. The machinery remained the same, at a nominal 112,500 SHP. The weight gain was used to work in some desired features that the RHN had stipulated. The number of 5”/51 AA-guns was doubled from two to four by moving the existing ones outboard on sponsons and adding two more on the other beam.

Thus presented, the new design weighed 11,250 tons std; 9,200 light and 13,325 full weight.
Hull dimensions were length: 620 ft wl, 640 ft overall (with the fitting of a real hurricane bow length was increased from the original 634 ft); beam: 64-10; draught: 20 ft mean.

The original completely unarmored design was altered by utilizing the saved weight margins to work in an armored upper deck 1.5 in thick. In addition, the magazines were protected by an additional deck of 80 lb thickness; the machinery and boiler rooms with a 60 lb STS deck. Also the gun houses, a variant of Lexington and Saratoga’s twins, but with a triple cradle instead, were armored with 80lb of STS as splinter protection. Barbettes were given 1 in protection. Bulkheads and funnel uptakes and the crowns and hoists of the battery were also given 80lb of STS as protection. Finally the conning tower was protected with 5 in armor. The protection amounted to 664 tons on a hull weighing 4,899 tons. The machinery weighed 2,195 tons.

Orders were placed for the first unit; named Psara, taking the name of the second of the battleships, it was to be laid down at Philadelphia Navy Yard, Philadelphia, PA. On April 16, 1924 the first rivet was driven into her bottom plates; on Oct. 27, 1926 she was launched, and on June 4, 1927 she sailed down the Delaware River out into the Atlantic, commissioned as a unit of the RHN. At a flag-changing ceremony at Wilmington her new Hellenic crew took possession of the vessel.
On July 1 the Psara sailed on a course SW-by-W off the Nantucket to establish her potential. On a one-and-a-half hour full power trial she attained the phenomenal speed of 39.14 knots with a forced draught of 126,788 SHP. She was fitted with her gun houses but without the guns, and so was some 150 tons light, but the weather was rather inclement with adversary wind-speeds up to 17 mi/s, and choppy seas.

Her sisters were both laid down at New York Shipbuilding Corp., Camden, NJ, only a stone’s throw from where the Psara was building.
The respective dates of their completion were:
Spetsai: laid down April 7, 1925; launched May 5, 1928; completed Jan. 1, 1929
Hydra: laid down April 2, 1925; launched July 3, 1929; completed Feb. 20, 1930.
Both ships made their trials off the Staten Island in more favorable weather than Psara had experienced. The Hydra achieved an unheard of 41.63 knots on a straight quarter-mile run at a forced power of 122,083 SHP, on March 12, 1930. The following day she made 42.04 knots with 127.000 SHP, though the time and duration was never logged.
Spetsai, during her first run, over shallow sand bars, on March 21, 1929 made a disappointing 35.09 knots, but two days later she ran in deeper water and attained 39.01 knots. Though her power output log has been lost, she must have had a considerable reserve remaining, since, during the great maneuvers in 1935/36 she is known to have touched 42 knots without difficulty.

Thus all three turned out to be most satisfactory, and in service they gained a high reputation as steady, albeit slightly stiff, gun platforms and reliable ships overall.

The guns fitted were of a Vickers design, but instead of the Kriti’s manually handled mounts, the new vessels received Vickers remodeled caliber 55 Mk VI with electric hoists and hydraulic training and elevation. This sped up the rate of fire considerably.
The shells were the same as on the Kriti; 90, 7 kg with cordite bags weighing 23 kg. The handling rooms were above the ready rooms with the magazines beneath. Flashtight doors were provided. Range of the new ordnance was 29,000 yards with 55 degrees elevation and 8 degrees depression. The three gun tubs rested in a common cradle in a gun house which was a slightly widened variant of the ones used for the Lexington-class carriers. These were only protected against splinter. Fresh water was carried in their overhangs, with a third of the space devoted to carry oil. The three to four aircraft that were carried were stowed abaft the second funnel on an unprotected weather deck. Normally two were stowed on the catapults. Their gasoline was stowed in tanks in the forward section of the ship, a position first proposed for the US preliminary design which became the Salt Lake City class.

The machinery was split into two separate units with two boiler rooms ahead of No. 1 Engine Room and two abaft it and ahead of No. 2 Engine Room. Four geared Curtis Turbines drove four shafts. There was one balanced rudder and they had a characteristic ‘vee’ shaped aft floatplane (flutes), greatly reducing hydrodynamic resistance. The hull lines were unusually fine at the ends, fullness occurring just abaft No. 1 Engine Room, resulting in a steady roll with only a marginal tendency for pitch.
The endurance was 9,000 nm at 15 knots, a more than adequate radius for RHN needs.

Crew amounted to 40 officers and 625 enlisted; as flagship an additional 12 staff-officers and 25 cadets were embarked.

I give you the graceful Psara-class Scout Cruisers, here represented by the name giver as of 1935, with three Loire-Nieuport 130 float planes embarked.
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Last edited by bezobrazov on August 24th, 2012, 12:03 am, edited 5 times in total.

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SrGopher
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 13th, 2011, 2:26 am
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It is quite an eccentric design! I especially like the slight mix in American and British design. Although, you might have too many AA machine guns on her.

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Blackbuck
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 13th, 2011, 8:19 am
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What an interesting design I rather like how she looks, good design or not she has nice lines.

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Ashley
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 13th, 2011, 10:43 am
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SrGopher wrote:
It is quite an eccentric design! I especially like the slight mix in American and British design. Although, you might have too many AA machine guns on her.
Yes, a very well looking drawing, looks like a ship with good stamina. The fixed installed MGs really might be too much, but the amount of positions would be ok. The MGs were stored most times.

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bezobrazov
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 13th, 2011, 11:14 am
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You're right ashley, about the storage...except, if you read the background story you'll find out why she has them and to that extent...besides, by 1935 - yes, even at that relatively early time frame, she most certainly has not too many mg:s but rather too few... But I have a long-term goal of making her as she appeared in 1939, rebuilt as a 6"-gun cruiser...

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emperor_andreas
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 14th, 2011, 3:57 am
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I agree, Blackbuck...very nice lines! Good stamina, Ashley? Try INCREDIBLE stamina! A 42-knot CA? WOW!

-Matt

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Carthaginian
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 14th, 2011, 4:24 am
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I gotta Springsharp this one. :D
Awesome ship, Bezobrazov!


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odysseus1980
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 14th, 2011, 6:54 am
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Very nice ship,I like it!Please,Bezobrazov,can I use Psara class as a design base for my CA?I tried a Trento class based CA,but it does not look right to me.I have specs for the Loire 130.Is it possible to upload full specifications for Psara?


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bezobrazov
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 14th, 2011, 10:47 am
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LOL, go for it Carthaginian! I've tried to use the Springsharp, bu never got the blasted thing to work properly! I guess I'm so old-fashioned...

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Carthaginian
Post subject: Re: Royal Hellenic Navy's Cruiser Force 1925-41Posted: October 14th, 2011, 4:52 pm
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bezobrazov wrote:
LOL, go for it Carthaginian! I've tried to use the Springsharp, bu never got the blasted thing to work properly! I guess I'm so old-fashioned...
Thanks- I've toyed with the design a bit... your HP figures give a 33 knot 'service speed' for the ship, which is Springsharps' way of saying that your ship can do that speed in normal service. Running a speed trial, light ship, with nothing but fuel and the ship's metal parts aboard, I'm not sure what she'd be able to do.

I'm a bit confused by your protection scheme and not sure that I can duplicate it in SS.
For instance what is "80lb of STS" equivalent to in inches? :oops: If I knew that, I'd be able to give a better simulation of your ship.
Also, I CAN say that Springsharp will call them 'poor seaboats' simply because they will not be able to plow through rough seas at max speed without doing some kind of damage- like breaking their backs. They should actually be fairly good boats for the Med.

That aside, I can say that everything you wanted on the ship will fit without a doubt... with some buoyancy left over.


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