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[SIZE=3]Vasilashki, Bulgarian Patrol Gunboat laid down 1938[/SIZE]

Displacement:
1,800 t light; 1,889 t standard; 2,247 t normal; 2,534 t full load

Dimensions: Length overall / water x beam x draught
375.86 ft / 355.00 ft x 41.00 ft x 14.00 ft (normal load)
114.56 m / 108.20 m x 12.50 m x 4.27 m

Armament:
4 - 5.91" / 150 mm guns in single mounts, 102.98lbs / 46.71kg shells, 1938 Model
Quick firing guns in deck mounts with hoists
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (4x2 guns), 1.95lbs / 0.88kg shells, 1938 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
2 - 1.57" / 40.0 mm guns (1x2 guns), 1.95lbs / 0.89kg shells, 1938 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
Weight of broadside 428 lbs / 194 kg
Shells per gun, main battery: 180
8 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1.50" / 38 mm 230.75 ft / 70.33 m 7.68 ft / 2.34 m
Ends: Unarmoured
Main Belt covers 100 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.00" / 76 mm 2.00" / 51 mm 2.00" / 51 mm

- Armour deck: 0.50" / 13 mm, Conning tower: 4.00" / 102 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 10,774 shp / 8,037 Kw = 24.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 645 tons

Complement:
163 - 212

Cost:
£0.841 million / $3.364 million

Distribution of weights at normal displacement:
Armament: 53 tons, 2.4 %
Armour: 258 tons, 11.5 %
- Belts: 111 tons, 4.9 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 47 tons, 2.1 %
- Armour Deck: 85 tons, 3.8 %
- Conning Tower: 15 tons, 0.7 %
Machinery: 295 tons, 13.1 %
Hull, fittings & equipment: 1,113 tons, 49.5 %
Fuel, ammunition & stores: 447 tons, 19.9 %
Miscellaneous weights: 80 tons, 3.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
5,191 lbs / 2,355 Kg = 50.4 x 5.9 " / 150 mm shells or 1.5 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 1.7 ft / 0.5 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.53
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.386
Length to Beam Ratio: 8.66 : 1
'Natural speed' for length: 22.12 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 35
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 7.00 ft / 2.13 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 24.00 ft / 7.32 m
- Forecastle (20 %): 21.00 ft / 6.40 m
- Mid (50 %): 19.00 ft / 5.79 m (12.00 ft / 3.66 m aft of break)
- Quarterdeck (15 %): 12.00 ft / 3.66 m
- Stern: 12.00 ft / 3.66 m
- Average freeboard: 16.44 ft / 5.01 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 66.1 %
- Above water (accommodation/working, high = better): 105.2 %
Waterplane Area: 9,231 Square feet or 858 Square metres
Displacement factor (Displacement / loading): 166 %
Structure weight / hull surface area: 67 lbs/sq ft or 326 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.87
- Longitudinal: 3.54
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weights:
- 35 tons for catapult and crane
- 15 tons for aircraft and gear
- 15 tons for DC
- 10 tons for Hydrophones and other gear
- 5 tons for Rum

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The ship is of course based upon the dashing-looking USS Erie of 1936. The goal was to get four 15cm guns on a moderately fast hull, with a floatplane to enhance visual coverage. Roles would include convoy escorts, foreign port visits, shore gunfire support, etc, etc, etc...

Just an exercise in design at the moment.

The Erie is a nice design to use as a base. Might be a good idea to extend the forecastle aft and group the torpedo launchers into quad mounts to save space.

Mexico built a very similar ship both in design and purpose. Take a look at the Obregons :
http://wesworld.jk-clan.de/thread.php?threadid=3233&sid=

Overall looks like a very good design, thought the armor is quite heavy.

Quoted

Originally posted by Desertfox
Mexico built a very similar ship both in design and purpose. Take a look at the Obregons :
http://wesworld.jk-clan.de/thread.php?threadid=3233&sid=

Overall looks like a very good design, thought the armor is quite heavy.

Thanks. Though "the armour is quite heavy" is a selling point.

The floatplane takes up a lot of valuable space and weight. It'll already be a reasonably crowded ship. Adding the floatplane cuts down on space for accommodation quite severely. For a patrol vessel I think the crew comfort may be more useful.

She's a lot like a 150mm armed version of my 125mm armed Tijgerhaai class, which as I like Erie class as well, could be related. For my purposes the DP is more useful, plus I wanted the higher elevations for shore bombardment.

For my purposes, the point of the armor was to exclude HE/Common rounds and force the fore to use less damaging SAP/AP to actually do anything critical. Still quite possible to soft kill them.

Hindsight says I probably should have gone with the same distribution you have, rounded the deck up to 15mm instead, going with 30mm on the belt.

Little curious as to the long range, it is the same as the Tijgerhaai, which has call to transit from Kongo-DEI.

As for seaplanes, OTL Dutch did fit them on destroyer sized vessels, but my understanding is it wasn't a resounding success. Still, the Bulgarians might not know that quite yet.

Overall I like this patrol boat, it does what it says on the tin. Useful armament and I think the floatplane is essential for a vessel of this type. If space is a problem ditch the catapult and just use the crane to aid operations.

The twin torpedo mounts seems a little odd, I'd ditch two and just have four tubes, more than enough for a patrol vessel.

The belt and deck armour are only good for splinter protection, I'd remove them myself to save weight but its probably useful to have some protection for the magazines at least.