WesWorld

A first sketch of a design for a patrol vessel intended for service in the southern portion of the archipelago. She would carry an intervention force of Marines, be sufficiently well armed to overawe any local opposition or intruding small craft. There's reserve strength in the current design - the question being how to work toward an optimal design without sacrificing seakeeping and stability.

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TBD, Philippine Large Patrol Ship laid down 1944

Displacement: 1,625 t light; 1,721 t standard; 2,058 t normal; 2,328 t full load

Dimensions: Length overall / water x beam x draught

286.53 ft / 278.87 ft x 33.63 ft x 12.80 ft (normal load) [87.33 m / 85.00 m x 10.25 m x 3.90 m]

Armament:

4 - 4.53" / 115 mm guns (2x2 guns), 46.40lbs / 21.05kg shells, 1944 Model Dual purpose guns in deck mounts on centreline ends, evenly spread
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1944 Model Anti-aircraft guns in deck mounts on centreline ends, evenly spread, all raised mounts - superfiring
4 - 0.59" / 15.0 mm guns in single mounts, 0.10lbs / 0.05kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, evenly spread, all raised mounts
Weight of broadside 191 lbs / 87 kg
Shells per gun, main battery: 500

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -

Conning tower: 0.98" / 25 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 6,016 shp / 4,488 Kw = 20.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 607 tons

Complement: 152 - 198

Cost: £0.662 million / $2.650 million

Distribution of weights at normal displacement:

Armament: 24 tons, 1.2 %
Armour: 12 tons, 0.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 8 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 154 tons, 7.5 %
Hull, fittings & equipment: 1,196 tons, 58.1 %
Fuel, ammunition & stores: 433 tons, 21.0 %
Miscellaneous weights: 240 tons, 11.7 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 5,472 lbs / 2,482 Kg = 117.9 x 4.5 " / 115 mm shells or 1.9 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.2 ft / 0.4 m
Roll period: 13.0 seconds
Steadiness - As gun platform (Average = 50 %): 57 %
- Recoil effect (Restricted arc if above 1.00): 0.18
Seaboat quality (Average = 1.00): 1.91

Hull form characteristics:

Hull has rise forward of midbreak and transom stern
Block coefficient: 0.600
Length to Beam Ratio: 8.29: 1
'Natural speed' for length: 19.13 kts
Power going to wave formation at top speed: 56 %
Trim (Max stability = 0, Max steadiness = 100): 30
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19.69 ft / 6.00 m
- Forecastle (20 %): 18.86 ft / 5.75 m
- Mid (50 %): 18.04 ft / 5.50 m (11.48 ft / 3.50 m aft of break)
- Quarterdeck (20 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 15.12 ft / 4.61 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 49.1 %
- Above water (accommodation/working, high = better): 134.1 %
Waterplane Area: 7,150 Square feet or 664 Square metres
Displacement factor (Displacement / loading): 274 %
Structure weight / hull surface area: 89 lbs/sq ft or 433 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.61
- Longitudinal: 6.99
- Overall: 1.87
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weight

200 tons reserved for accommodation of Marine action group (100 officers and men)
40 tons reserved for tropicalization

Perhaps group the main battery forward, and add some miscellaneous weight for a couple of landing craft aft?

Not sure what the transom stern adds given the ship's top speed.

I'd probably add another 2x2 35mm mounts on the sides. I think Rocky's idea of a couple of small Landing Craft is probably a good one.
Maybe add 50 tons for future growth. Other than that I can't think of any other ways to absorb 0.87 of extra strength unless you reduce the BC further.

Thank you for the suggestions. In playing with the variables, I've come up with a much smaller (and less expensive) proposal that seems to retain much of the original design's capabilities on a smaller hull. I've added a provision for landing craft and gear, and might squeeze something out of the 40-tons of tropical amenities for sensors. It still is slightly above optimal, but not absurdedly so. Any further suggestions?

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TBD, Philippine Escort Sloop laid down 1944

Displacement: 1,070 t light; 1,157 t standard; 1,386 t normal; 1,570 t full load

Dimensions: Length overall / water x beam x draught

237.32 ft / 229.66 ft x 33.79 ft x 12.14 ft (normal load) [72.33 m / 70.00 m x 10.30 m x 3.70 m]

Armament:

4 - 4.53" / 115 mm guns (2x2 guns), 48.50lbs / 22.00kg shells, 1944 Model Dual purpose guns in deck mounts on centreline ends, evenly spread
8 - 1.38" / 35.0 mm guns (4x2 guns), 1.31lbs / 0.59kg shells, 1944 Model Anti-aircraft guns in deck mounts on centreline ends, evenly spread, all raised mounts - superfiring
8 - 0.59" / 15.0 mm guns (4x2 guns), 0.10lbs / 0.05kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, evenly spread, all raised mounts
Weight of broadside 205 lbs / 93 kg
Shells per gun, main battery: 500

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -

Conning tower: 0.98" / 25 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 7,203 shp / 5,373 Kw = 21.00 kts
Range 6,000nm at 15.00 kts
Bunker at max displacement = 413 tons

Complement: 113 - 147

Cost: £0.564 million / $2.257 million

Distribution of weights at normal displacement:

Armament: 25 tons, 1.8 %
Armour: 12 tons, 0.9 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 10 tons, 0.7 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 184 tons, 13.3 %
Hull, fittings & equipment: 529 tons, 38.2 %
Fuel, ammunition & stores: 316 tons, 22.8 %
Miscellaneous weights: 320 tons, 23.1 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 2,223 lbs / 1,009 Kg = 47.9 x 4.5 " / 115 mm shells or 0.8 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.2 ft / 0.4 m
Roll period: 13.0 seconds
Steadiness - As gun platform (Average = 50 %): 54 %
- Recoil effect (Restricted arc if above 1.00): 0.22
Seaboat quality (Average = 1.00): 1.65

Hull form characteristics:

Hull has rise forward of midbreak
Block coefficient: 0.515
Length to Beam Ratio: 6.80: 1
'Natural speed' for length: 15.15 kts
Power going to wave formation at top speed: 64 %
Trim (Max stability = 0, Max steadiness = 100): 33
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19.69 ft / 6.00 m
- Forecastle (20 %): 18.86 ft / 5.75 m
- Mid (50 %): 18.04 ft / 5.50 m (11.48 ft / 3.50 m aft of break)
- Quarterdeck (20 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 15.12 ft / 4.61 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 85.7 %
- Above water (accommodation/working, high = better): 132.3 %
Waterplane Area: 5,242 Square feet or 487 Square metres
Displacement factor (Displacement / loading): 155 %
Structure weight / hull surface area: 51 lbs/sq ft or 248 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.89
- Longitudinal: 6.46
- Overall: 1.08
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weight

200 tons reserved for accommodation of Marine action group (100 officers and men)
40 tons reserved for tropicalization
80 tons reserved for landing craft (2) and handling gear

Hmm...

I'm wondering if the ship's too small now, at least for what I perceive the ship's mission to be. It's not all that much larger now than a Flower class corvette at the moment, and with that troop complement aboard, I wonder if it'd almost be half landing ship by that point.

I'm also starting to wonder if it's perhaps over-gunned with four DP guns.

Quoted

Originally posted by Brockpaine
Hmm...

I'm wondering if the ship's too small now, at least for what I perceive the ship's mission to be. It's not all that much larger now than a Flower class corvette at the moment, and with that troop complement aboard, I wonder if it'd almost be half landing ship by that point.

I'm also starting to wonder if it's perhaps over-gunned with four DP guns.

That is a concern I have myself.

Looked at realistically, the design is over-gunned - though SS says everything is hunky-dory. I am just not certain where to pitch the middle ground in this case. Maybe something at around 1200-1300 tons light, but if so SS would be giving all sort of warnings.

Perhaps in this instance it is better to heed reality rather than the computer program?

Here is a quick revision pitched half-way between the two, size-wise. I think it is closer to reality but SS still shows a lot of reserve strength; and maybe that is a good thing in a smaller ship design.

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TBD, Philippine Large Patrol Ship laid down 1944

Displacement:
1,480 t light; 1,572 t standard; 1,884 t normal; 2,133 t full load

Dimensions: Length overall / water x beam x draught
273.41 ft / 265.75 ft x 34.28 ft x 12.80 ft (normal load)
83.33 m / 81.00 m x 10.45 m x 3.90 m

Armament:
4 - 4.53" / 115 mm guns (2x2 guns), 46.40lbs / 21.05kg shells, 1944 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on centreline ends, evenly spread, all raised mounts - superfiring
4 - 0.59" / 15.0 mm guns in single mounts, 0.10lbs / 0.05kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 191 lbs / 87 kg
Shells per gun, main battery: 500

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -

- Conning tower: 0.98" / 25 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 6,675 shp / 4,979 Kw = 20.00 kts
Range 7,000nm at 15.00 kts
Bunker at max displacement = 561 tons

Complement:
142 - 185

Cost:
£0.644 million / $2.577 million

Distribution of weights at normal displacement:
Armament: 24 tons, 1.3 %
Armour: 12 tons, 0.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 8 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 170 tons, 9.0 %
Hull, fittings & equipment: 934 tons, 49.6 %
Fuel, ammunition & stores: 404 tons, 21.4 %
Miscellaneous weights: 340 tons, 18.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
3,939 lbs / 1,787 Kg = 84.9 x 4.5 " / 115 mm shells or 1.3 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.2 ft / 0.4 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0.17
Seaboat quality (Average = 1.00): 1.90

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.566
Length to Beam Ratio: 7.75 : 1
'Natural speed' for length: 16.30 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 29
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19.69 ft / 6.00 m
- Forecastle (20 %): 18.86 ft / 5.75 m
- Mid (50 %): 18.04 ft / 5.50 m (11.48 ft / 3.50 m aft of break)
- Quarterdeck (20 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 15.12 ft / 4.61 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 61.9 %
- Above water (accommodation/working, high = better): 129.6 %
Waterplane Area: 6,452 Square feet or 599 Square metres
Displacement factor (Displacement / loading): 213 %
Structure weight / hull surface area: 75 lbs/sq ft or 365 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.33
- Longitudinal: 6.42
- Overall: 1.56
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weight

200 tons reserved for accommodation of Marine action group (100 officers and men)
40 tons reserved for tropicalization
80 tons reserved for landing craft (2) and handling gear
20 tons reserved for radar

I think that's looking a lot better. I'm mainly looking for comparison at the APD variants of the WWII destroyer escorts which are longer yet, and have only one 5"/38 gun rather than 4x4.5".

What I dont understand is, the Agbayanis were designed for this very mission and would only be 10 years old... why where they sold off then? Not that I'm complaining.

Perhaps the same reason I've been selling or scrapping many of the Chilean ships, including some which are rather new. There are differences in how some players perceive the needs of the mission, and those perceptions are reflected back to the choice of ship designs.

Quoted

Originally posted by Desertfox
What I dont understand is, the Agbayanis were designed for this very mission and would only be 10 years old... why where they sold off then? Not that I'm complaining.

When I look at the mission envisaged for this vessel, and then look at the Agbayani class 'things', I don't see the latter as being designed 'for that very mission'. I'm not certain what they were designed for.

Brock is quite correct that perceptions of needs change when players change; and there is no guarantee at this point that this type of vessel will be pursued. Things could intervene between now (1942) and then (1944) which would preclude their construction.

Quoted

Originally posted by Brockpaine
I think that's looking a lot better. I'm mainly looking for comparison at the APD variants of the WWII destroyer escorts which are longer yet, and have only one 5"/38 gun rather than 4x4.5".

Point well taken. I've been thinking along those lines myself. I've made another revision that drops the twin 115mm mount aft, leaving only the twin 35mm AA. That should make it easier to fit the landing craft and their davits and not have issues with blast effects or obstructions.

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TBD, Philippine Large Patrol Ship laid down 1944

Displacement:
1,465 t light; 1,531 t standard; 1,886 t normal; 2,170 t full load

Dimensions: Length overall / water x beam x draught
273.41 ft / 265.75 ft x 34.28 ft x 12.80 ft (normal load)
83.33 m / 81.00 m x 10.45 m x 3.90 m

Armament:
2 - 4.53" / 115 mm guns (1x2 guns), 46.40lbs / 21.05kg shells, 1944 Model
Dual purpose guns in deck mount
on centreline forward
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on centreline ends, evenly spread, all raised mounts - superfiring
4 - 0.59" / 15.0 mm guns in single mounts, 0.10lbs / 0.05kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 98 lbs / 45 kg
Shells per gun, main battery: 500

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -

- Conning tower: 0.98" / 25 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 6,680 shp / 4,983 Kw = 20.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 639 tons

Complement:
143 - 186

Cost:
£0.575 million / $2.300 million

Distribution of weights at normal displacement:
Armament: 12 tons, 0.7 %
Armour: 8 tons, 0.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 5 tons, 0.3 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 171 tons, 9.0 %
Hull, fittings & equipment: 934 tons, 49.5 %
Fuel, ammunition & stores: 421 tons, 22.3 %
Miscellaneous weights: 340 tons, 18.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
4,343 lbs / 1,970 Kg = 93.6 x 4.5 " / 115 mm shells or 1.5 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.2 ft / 0.4 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0.09
Seaboat quality (Average = 1.00): 1.90

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.566
Length to Beam Ratio: 7.75 : 1
'Natural speed' for length: 16.30 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 29
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19.69 ft / 6.00 m
- Forecastle (20 %): 18.86 ft / 5.75 m
- Mid (50 %): 18.04 ft / 5.50 m (11.48 ft / 3.50 m aft of break)
- Quarterdeck (20 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 15.12 ft / 4.61 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 56.2 %
- Above water (accommodation/working, high = better): 128.7 %
Waterplane Area: 6,456 Square feet or 600 Square metres
Displacement factor (Displacement / loading): 239 %
Structure weight / hull surface area: 75 lbs/sq ft or 364 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.36
- Longitudinal: 6.40
- Overall: 1.59
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weight

200 tons reserved for accommodation of Marine action group (100 officers and men)
40 tons reserved for tropicalization
80 tons reserved for landing craft (2) and handling gear
20 tons reserved for radar

One option facing the Philippine Navy is whether to tie its long-range reconnaissance force (PBY Catalinas) to land bases or construct seaplane tenders/aviation support ships of some sort to supplement or replace those presently in service. The flexibility of mobile basing has its attractions. The following design has been proposed.

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TBD, Philippine Small Seaplane Tender laid down 1944

Displacement: 1,605 t light; 1,684 t standard; 2,500 t normal; 3,153 t full load

Dimensions: Length overall / water x beam x draught

309.99 ft / 303.48 ft x 41.99 ft x 12.47 ft (normal load) [94.48 m / 92.50 m x 12.80 m x 3.80 m]

Armament:

2 - 4.53" / 115 mm guns in single mounts, 48.50lbs / 22.00kg shells, 1944 Model Dual purpose guns in deck mounts on centreline, all forward, 1 raised mount
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, evenly spread
4 - 0.59" / 15.0 mm guns (2x2 guns), 0.10lbs / 0.05kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, evenly spread
Weight of broadside 103 lbs / 47 kg
Shells per gun, main battery: 500

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.79" / 20 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -

Conning tower: 0.98" / 25 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 7,591 shp / 5,663 Kw = 20.00 kts
Range 16,000nm at 15.00 kts
Bunker at max displacement = 1,468 tons

Complement: 176 - 229

Cost: £0.630 million / $2.520 million

Distribution of weights at normal displacement:

Armament: 12 tons, 0.5 %
Armour: 11 tons, 0.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 7 tons, 0.3 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 4 tons, 0.2 %
Machinery: 194 tons, 7.8 %
Hull, fittings & equipment: 797 tons, 31.9 %
Fuel, ammunition & stores: 895 tons, 35.8 %
Miscellaneous weights: 590 tons, 23.6 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 6,232 lbs / 2,827 Kg = 134.3 x 4.5 " / 115 mm shells or 1.8 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 1.9 ft / 0.6 m
Roll period: 12.7 seconds
Steadiness - As gun platform (Average = 50 %): 77 %
- Recoil effect (Restricted arc if above 1.00): 0.05
Seaboat quality (Average = 1.00): 1.98

Hull form characteristics:

Hull has raised forecastle, rise forward of midbreak
Block coefficient: 0.551
Length to Beam Ratio: 7.23: 1
'Natural speed' for length: 17.42 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 39
Bow angle (Positive = bow angles forward): 8.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.97 ft / 7.00 m
- Forecastle (20 %): 20.54 ft / 6.26 m (20.51 ft / 6.25 m aft of break)
- Mid (50 %): 18.04 ft / 5.50 m (11.48 ft / 3.50 m aft of break)
- Quarterdeck (20 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 15.83 ft / 4.82 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 56.6 %
- Above water (accommodation/working, high = better): 148.1 %
Waterplane Area: 8,900 Square feet or 827 Square metres
Displacement factor (Displacement / loading): 230 %
Structure weight / hull surface area: 54 lbs/sq ft or 263 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.70
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Low stowed cargo simmed as additional bunkers. Actual radius 8,000 nm - 484 tons, leaving 400 tons cargo - 300 tons aviation fuel, 100 tons fresh water.

Breakdown of miscellaneous weight

Reserved for aircraft repair and servicing shop - 100 tons
Reserved for spare parts storage and ordnance - 100 tons
Reserved for service crew accommodation (50 officers and men) - 100 tons
Reserved for aircraft handling gear and cranes - 90 tons
Reserved for tropicalization - 40 tons
Reserved for radar - 20 tons
Reserved for future growth - 30 tons

Hmmm, not sure on the flying boat tender. Yes its a snazzy idea on paper but I'm sure the Phillippines has enough inlets and bays across its numerous islands for redudancy and enough geographical spread to give excellent coverage. For a long-range type Chinese waters aren't that far away.

Still if you have the spare tonnage it might be worth it.

I share your anguish over small ships, I've been toying with various sloops and small vessels and keep finding either excess hull strengh or absurdly optimistic specs on small hulls. A happy medium is sometimes hard to find.

Hmm, interesting indeed.

Quoted

Originally posted by Hood
Hmmm, not sure on the flying boat tender. ... ... Still if you have the spare tonnage it might be worth it.

Yes, whether I would have the tonnage to spare is a very important question. At this point, I am not certain, and it depends on procurement choices made during 1943, and they are dependent upon the political and military situation, which is unclear at the moment.

Certainly there are plenty of inlets and bays, but they alone do not a viable base make; there needs to be a minimum of facilities and - within reason - I can't set up seaplane bases *everywhere*. So, it it were affordable, having a small tender or two would be attractive.

Merely sounding out options and potential designs at this point. There is much water still to flow under the bridge before we lay down keels.

I kinda like the little tender.

It could allow rapid establishment of a forward base in captured enemy territory or undefended friendly territory.

It could serve as a rapid replacement to shore-based facilities that might be disabled by enemy action, and in times of peace, it could probably also serve as a general purpose supply ship supporting these facilities.

Quoted

Originally posted by The Rock Doctor
I kinda like the little tender.

It could allow rapid establishment of a forward base in captured enemy territory or undefended friendly territory.

It could serve as a rapid replacement to shore-based facilities that might be disabled by enemy action, and in times of peace, it could probably also serve as a general purpose supply ship supporting these facilities.

All those are points in the design's favor, and why I would like to have one or two, to replace the aging tenders I have in service. It's based on the Barnegat's overall dimensions, and so would be handy for adaptation to a variety of roles. While baselined for 1944, it is possible that funds could be found in later years. Time will tell.

At the opposite end of the spectrum from the large patrol vessel, I am considering a small escort sloop design. It is a natural outgrowth of the current minesweeper designs that the Philippine Navy has been building.

I personally like the size and seakeeping characteristics of the design. I've tried to keep the armament reasonable, though I suppose SS would allow me to augment it. I think it would be sufficient for patrol work in the southern and western areas of the Philippine sea frontier. Its weakness would be a relative lack of firepower if confronted with serious air attack.

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TBD, Philippine Escort Sloop laid down 1944

Displacement: 635 t light; 680 t standard; 834 t normal; 957 t full load

Dimensions: Length overall / water x beam x draught

234.32 ft / 229.66 ft x 27.89 ft x 10.17 ft (normal load) [71.42 m / 70.00 m x 8.50 m x 3.10 m]

Armament:

2 - 4.53" / 115 mm guns in single mounts, 46.40lbs / 21.05kg shells, 1944 Model Dual purpose guns in deck mounts on centreline ends, evenly spread
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, all amidships
Weight of broadside 98 lbs / 44 kg
Shells per gun, main battery: 500

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.59" / 15 mm -
2nd: 0.39" / 10 mm - -

Conning tower: 0.98" / 25 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 5,946 shp / 4,436 Kw = 22.00 kts
Range 5,700nm at 15.00 kts
Bunker at max displacement = 277 tons

Complement: 76 - 100

Cost: £0.362 million / $1.447 million

Distribution of weights at normal displacement:

Armament: 12 tons, 1.5 %
Armour: 7 tons, 0.9 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 5 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 2 tons, 0.2 %
Machinery: 152 tons, 18.2 %
Hull, fittings & equipment: 324 tons, 38.8 %
Fuel, ammunition & stores: 199 tons, 23.9 %
Miscellaneous weights: 140 tons, 16.8 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 1,281 lbs / 581 Kg = 27.6 x 4.5 " / 115 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.0 seconds
Steadiness - As gun platform (Average = 50 %): 59 %
- Recoil effect (Restricted arc if above 1.00): 0.16
Seaboat quality (Average = 1.00): 1.57

Hull form characteristics:

Hull has rise forward of midbreak
Block coefficient: 0.448
Length to Beam Ratio: 8.24: 1
'Natural speed' for length: 15.15 kts
Power going to wave formation at top speed: 61 %
Trim (Max stability = 0, Max steadiness = 100): 38
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 17.39 ft / 5.30 m
- Forecastle (20 %): 16.08 ft / 4.90 m
- Mid (50 %): 14.76 ft / 4.50 m (8.53 ft / 2.60 m aft of break)
- Quarterdeck (15 %): 8.53 ft / 2.60 m
- Stern: 8.53 ft / 2.60 m
- Average freeboard: 12.21 ft / 3.72 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 91.7 %
- Above water (accommodation/working, high = better): 119.7 %
Waterplane Area: 4,079 Square feet or 379 Square metres
Displacement factor (Displacement / loading): 152 %
Structure weight / hull surface area: 40 lbs/sq ft or 193 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.85
- Longitudinal: 4.30
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of miscellaneous weight:

Reserved for dradis - 20 tons
Reserved for sonar - 30 tons
Reserved for A/S outfit - four A/S mortars, two D/C racks and 40 depth charges - 50 tons
Reserved for tropicalization - 20 tons
Reserved for future growth 20 tons

By 1944 one of the questions facing the Philippines will be whether to perpetuate its Surigao class light cruisers or embark on construction of something better. This study examines a roughly-comparable vessel with three triple 150mm mounts in place of four twin 150mm. Protection is on a modestly improved scale.

Thoughts?

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TBD, Philippine Light Cruiser laid down 1944

Displacement: 7,460 t light; 7,835 t standard; 8,593 t normal; 9,200 t full load

Dimensions: Length overall / water x beam x draught

570.57 ft / 557.74 ft x 57.41 ft x 17.55 ft (normal load) [173.91 m / 170.00 m x 17.50 m x 5.35 m]

Armament:

9 - 5.91" / 150 mm guns (3x3 guns), 106.92lbs / 48.50kg shells, 1944 Model Breech loading guns in turrets (on barbettes) on centreline ends, majority forward, 1 raised mount - superfiring
8 - 4.53" / 115 mm guns (4x2 guns), 48.50lbs / 22.00kg shells, 1944 Model Dual purpose guns in deck mounts with hoists on side, evenly spread
12 - 1.38" / 35.0 mm guns (6x2 guns), 1.31lbs / 0.59kg shells, 1944 Model Anti-aircraft guns in deck mounts on side, evenly spread, all raised mounts
Weight of broadside 1,366 lbs / 620 kg
Shells per gun, main battery: 250
8 - 24.0" / 610 mm above water torpedoes

Armour:

Belts: Width (max) Length (avg) Height (avg)
Main: 3.15" / 80 mm 360.89 ft / 110.00 m 9.02 ft / 2.75 m
Ends: Unarmoured
Main Belt covers 100 % of normal length

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.15" / 80 mm 2.36" / 60 mm 3.94" / 100 mm
2nd: 0.98" / 25 mm 0.59" / 15 mm 0.98" / 25 mm
3rd: 0.39" / 10 mm - -

Armour deck: 1.57" / 40 mm, Conning tower: 3.15" / 80 mm

Machinery:

Oil fired boilers, steam turbines, Geared drive, 2 shafts, 78,927 shp / 58,880 Kw = 33.00 kts
Range 7,600nm at 15.00 kts
Bunker at max displacement = 1,365 tons

Complement: 446 - 580

Cost: £4.583 million / $18.331 million

Distribution of weights at normal displacement:

Armament: 164 tons, 1.9 %
Armour: 1,408 tons, 16.4 %
- Belts: 429 tons, 5.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 283 tons, 3.3 %
- Armour Deck: 668 tons, 7.8 %
- Conning Tower: 28 tons, 0.3 %
Machinery: 2,016 tons, 23.5 %
Hull, fittings & equipment: 3,622 tons, 42.1 %
Fuel, ammunition & stores: 1,133 tons, 13.2 %
Miscellaneous weights: 250 tons, 2.9 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 12,239 lbs / 5,552 Kg = 118.9 x 5.9 " / 150 mm shells or 1.6 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 2.8 ft / 0.9 m
Roll period: 14.4 seconds
Steadiness - As gun platform (Average = 50 %): 56 %
- Recoil effect (Restricted arc if above 1.00): 0.45
Seaboat quality (Average = 1.00): 1.13

Hull form characteristics:

Hull has a flush deck and transom stern
Block coefficient: 0.535
Length to Beam Ratio: 9.71: 1
'Natural speed' for length: 26.91 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 22.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 23.62 ft / 7.20 m
- Forecastle (49 %): 21.98 ft / 6.70 m
- Mid (50 %): 20.34 ft / 6.20 m
- Quarterdeck (15 %): 20.34 ft / 6.20 m
- Stern: 20.34 ft / 6.20 m
- Average freeboard: 21.48 ft / 6.55 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 95.6 %
- Above water (accommodation/working, high = better): 154.5 %
Waterplane Area: 22,936 Square feet or 2,131 Square metres
Displacement factor (Displacement / loading): 123 %
Structure weight / hull surface area: 97 lbs/sq ft or 474 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.93
- Longitudinal: 1.79
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent

Breakdown of miscellaneous weight

Reserved for radar and electronics suite: 100 tons
Tropicalization: 100 tons
Reserved for future growth: 50 tons