WesWorld

Deirdre-class Fisheries Patrol Ship
- LE Deirdre (F1) - 1936 (sold to Britain 1941)
- LE Eithne (F2) - 1936 (sold to Britain 1941)
- LÉ Aoife (F3) - built 1937
- LÉ Niamh (F4) - built 1937

Airmed-class Frigate
- LÉ Airmed (F5) (ex KDM Ask)
- LÉ Morrigan (F6] (ex KDM Asp)
- LÉ Danu (F7) (ex KDM Bog)

Shannon-class Frigate
- LÉ Shannon (F9) - built 1938
- LÉ Blackwater (F10) - laid down 1941
- LÉ Boyne (F11) - laid down 1941
- LÉ Liffey (F12) - laid down 1942

Maeve-class Oceanic Patrol Ship
- LÉ Maeve: laid down July 1942, completed June 1943
- LÉ Aisling - laid down January 1943, completed December 1943

Image originally by thesmilingassassin and creatively edited by me.

The Deirdre-class Fisheries Patrol Ships are designed to patrol the Atlantic fisheries regions and the Irish coastal zones. While not heavily-armed, they are sturdy and dependable sea-boats, and in a pinch, can serve as impromptu antisubmarine escorts and gunboats.

While nominally operated by the Irish Naval Service, these vessels had a partially civilian crew to operate the vessel; Irish Naval Service personnel composed the gun crew and a naval boarding team.

In 1941, the Irish government determined that only two fisheries patrol ships were necessary due to the growth of the Irish Naval Service's other branches, and sold the Dierdre and Eithne to Great Britain in exchange for surplus army equipment. Aoife and Niamh remain in service.

Quoted

Deirdre, Irish Fisheries Patrol Sloop laid down 1936

Displacement:
473 t light; 493 t standard; 620 t normal; 722 t full load

Dimensions: Length overall / water x beam x draught
229.19 ft / 223.00 ft x 32.00 ft x 8.00 ft (normal load)
69.86 m / 67.97 m x 9.75 m x 2.44 m

Armament:
2 - 3.70" / 94.0 mm guns (1x2 guns), 25.33lbs / 11.49kg shells, 1936 Model
Dual purpose guns in deck mount
on centreline forward
4 - 0.79" / 20.0 mm guns (2x2 guns), 0.24lbs / 0.11kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on centreline, evenly spread, all raised mounts
4 - 0.50" / 12.7 mm guns (2x2 guns), 0.06lbs / 0.03kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on centreline, evenly spread, all raised mounts
Weight of broadside 52 lbs / 24 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.57" / 40 mm 0.79" / 20 mm -
2nd: 0.79" / 20 mm 0.39" / 10 mm -
3rd: 0.59" / 15 mm 0.39" / 10 mm -

- Conning tower: 0.79" / 20 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,023 shp / 3,001 Kw = 22.00 kts
Range 6,000nm at 15.00 kts
Bunker at max displacement = 229 tons

Complement:
61 - 80

Cost:
£0.199 million / $0.797 million

Distribution of weights at normal displacement:
Armament: 6 tons, 1.0 %
Armour: 7 tons, 1.2 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 6 tons, 1.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.2 %
Machinery: 113 tons, 18.2 %
Hull, fittings & equipment: 316 tons, 51.0 %
Fuel, ammunition & stores: 147 tons, 23.7 %
Miscellaneous weights: 30 tons, 4.8 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,731 lbs / 785 Kg = 68.3 x 3.7 " / 94 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.24
Metacentric height 1.3 ft / 0.4 m
Roll period: 11.6 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.07
Seaboat quality (Average = 1.00): 1.62

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.380
Length to Beam Ratio: 6.97 : 1
'Natural speed' for length: 17.93 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 43
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 17.00 ft / 5.18 m
- Forecastle (20 %): 13.00 ft / 3.96 m
- Mid (50 %): 13.00 ft / 3.96 m
- Quarterdeck (15 %): 13.00 ft / 3.96 m
- Stern: 13.00 ft / 3.96 m
- Average freeboard: 13.32 ft / 4.06 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 73.8 %
- Above water (accommodation/working, high = better): 183.2 %
Waterplane Area: 4,514 Square feet or 419 Square metres
Displacement factor (Displacement / loading): 197 %
Structure weight / hull surface area: 40 lbs/sq ft or 195 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.83
- Longitudinal: 5.28
- 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

Breakdown of Weights:
20 tons for Depth Charges (war load)
10 tons for Hydrophones

In January 1937, two more ships of the Deirdre-class were laid down to a slightly improved design.

Quoted

Aoife, Irish Fisheries Patrol Sloop laid down 1937

Displacement:
478 t light; 498 t standard; 625 t normal; 727 t full load

Dimensions: Length overall / water x beam x draught
229.19 ft / 223.00 ft x 32.00 ft x 8.00 ft (normal load)
69.86 m / 67.97 m x 9.75 m x 2.44 m

Armament:
2 - 3.70" / 94.0 mm guns (1x2 guns), 25.33lbs / 11.49kg shells, 1937 Model
Dual purpose guns in deck mount
on centreline forward
4 - 0.79" / 20.0 mm guns (2x2 guns), 0.24lbs / 0.11kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on centreline, evenly spread, all raised mounts
4 - 0.50" / 12.7 mm guns (2x2 guns), 0.06lbs / 0.03kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on centreline, evenly spread, all raised mounts
Weight of broadside 52 lbs / 24 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.57" / 40 mm 0.79" / 20 mm -
2nd: 0.79" / 20 mm 0.39" / 10 mm -
3rd: 0.59" / 15 mm 0.39" / 10 mm -

- Conning tower: 0.79" / 20 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,053 shp / 3,024 Kw = 22.00 kts
Range 6,000nm at 15.00 kts
Bunker at max displacement = 228 tons

Complement:
62 - 81

Cost:
£0.207 million / $0.827 million

Distribution of weights at normal displacement:
Armament: 6 tons, 1.0 %
Armour: 7 tons, 1.2 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 6 tons, 1.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.2 %
Machinery: 112 tons, 18.0 %
Hull, fittings & equipment: 317 tons, 50.7 %
Fuel, ammunition & stores: 147 tons, 23.5 %
Miscellaneous weights: 35 tons, 5.6 %

Overall survivability and seakeeping ability:[/B]
Survivability (Non-critical penetrating hits needed to sink ship):
1,721 lbs / 781 Kg = 67.9 x 3.7 " / 94 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 1.3 ft / 0.4 m
Roll period: 11.8 seconds
Steadiness - As gun platform (Average = 50 %): 72 %
- Recoil effect (Restricted arc if above 1.00): 0.08
Seaboat quality (Average = 1.00): 1.61

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.383
Length to Beam Ratio: 6.97 : 1
'Natural speed' for length: 17.92 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 45
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 17.00 ft / 5.18 m
- Forecastle (20 %): 13.00 ft / 3.96 m
- Mid (50 %): 13.00 ft / 3.96 m
- Quarterdeck (15 %): 13.00 ft / 3.96 m
- Stern: 13.00 ft / 3.96 m
- Average freeboard: 13.32 ft / 4.06 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 73.8 %
- Above water (accommodation/working, high = better): 180.5 %
Waterplane Area: 4,520 Square feet or 420 Square metres
Displacement factor (Displacement / loading): 196 %
Structure weight / hull surface area: 40 lbs/sq ft or 196 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.83
- Longitudinal: 5.26
- 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

Breakdown of Weights:
20 tons for Depth Charges (war load)
10 tons for Hydrophones
5 tons Extra Gear

Ships in class:
- LE Deirdre - 1936 (sold to Britain 1941)
- LE Eithne - 1936 (sold to Britain 1941)
- LE Aoife - 1937 (to reserve, 1944)
- LE Niamh - 1937 (to reserve, 1944)

Airmed-class (ex-Ask-class), Irish (ex-Danish) Sloop laid down 1924

Displacement:
927 t light; 979 t standard; 1,191 t normal; 1,360 t full load

Dimensions: Length overall / water x beam x draught
286.73 ft / 280.00 ft x 33.00 ft x 10.00 ft (normal load)
87.40 m / 85.34 m x 10.06 m x 3.05 m

Armament:
3 - 5.12" / 130 mm guns in single mounts, 67.03lbs / 30.41kg shells, 1924 Model
Quick firing guns in deck mounts with hoists
on centreline ends, majority forward, 1 raised mount
6 - 2.24" / 57.0 mm guns (3x2 guns), 5.65lbs / 2.56kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
12 - 0.79" / 20.0 mm guns (6x2 guns), 0.24lbs / 0.11kg shells, 1924 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 238 lbs / 108 kg
Shells per gun, main battery: 200

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - -
2nd: 0.75" / 19 mm - -
3rd: 0.50" / 13 mm - -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 8,154 shp / 6,083 Kw = 24.00 kts
Range 10,000nm at 12.00 kts
Bunker at max displacement = 381 tons

Complement:
100 - 131

Cost:
£0.294 million / $1.175 million

Distribution of weights at normal displacement:
Armament: 30 tons, 2.5 %
Armour: 11 tons, 0.9 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 11 tons, 0.9 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 269 tons, 22.6 %
Hull, fittings & equipment: 568 tons, 47.7 %
Fuel, ammunition & stores: 264 tons, 22.2 %
Miscellaneous weights: 50 tons, 4.2 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,886 lbs / 856 Kg = 28.1 x 5.1 " / 130 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 1.2 ft / 0.4 m
Roll period: 12.4 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.52
Seaboat quality (Average = 1.00): 1.38

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.451
Length to Beam Ratio: 8.48 : 1
'Natural speed' for length: 19.48 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 51
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 18.50 ft / 5.64 m
- Forecastle (20 %): 16.50 ft / 5.03 m
- Mid (50 %): 16.50 ft / 5.03 m (9.75 ft / 2.97 m aft of break)
- Quarterdeck (15 %): 9.75 ft / 2.97 m
- Stern: 9.75 ft / 2.97 m
- Average freeboard: 13.29 ft / 4.05 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 98.1 %
- Above water (accommodation/working, high = better): 150.2 %
Waterplane Area: 6,128 Square feet or 569 Square metres
Displacement factor (Displacement / loading): 142 %
Structure weight / hull surface area: 53 lbs/sq ft or 258 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.88
- Longitudinal: 3.28
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily




[SIZE=3]Airmed, Danish-built Irish Sloop laid down 1924 (Rebuilt 1940)[/SIZE]

Displacement:
893 t light; 948 t standard; 1,191 t normal; 1,385 t full load

Dimensions: Length overall / water x beam x draught
286.73 ft / 280.00 ft x 33.00 ft x 10.00 ft (normal load)
87.40 m / 85.34 m x 10.06 m x 3.05 m

Armament:
3 - 4.50" / 114 mm guns in single mounts, 45.56lbs / 20.67kg shells, 1940 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, majority forward, 1 raised mount
2 - 1.57" / 40.0 mm guns (1x2 guns), 1.95lbs / 0.89kg shells, 1940 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
4 - 1.57" / 40.0 mm guns (2x2 guns), 1.95lbs / 0.89kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
12 - 0.79" / 20.0 mm guns (1x12 guns), 0.24lbs / 0.11kg shells, 1924 Model
Machine guns in deck mount
on side, all raised guns
Weight of broadside 151 lbs / 69 kg
Shells per gun, main battery: 350

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - -
2nd: 0.75" / 19 mm - -
3rd: 0.50" / 13 mm - -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 8,154 shp / 6,083 Kw = 24.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 438 tons

Complement:
100 - 131

Cost:
£0.240 million / $0.960 million

Distribution of weights at normal displacement:
Armament: 19 tons, 1.6 %
Armour: 8 tons, 0.7 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 8 tons, 0.7 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 218 tons, 18.3 %
Hull, fittings & equipment: 547 tons, 45.9 %
Fuel, ammunition & stores: 298 tons, 25.1 %
Miscellaneous weights: 100 tons, 8.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,212 lbs / 1,003 Kg = 48.5 x 4.5 " / 114 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.14
Metacentric height 1.2 ft / 0.4 m
Roll period: 12.6 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 1.40

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.451
Length to Beam Ratio: 8.48 : 1
'Natural speed' for length: 19.48 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 18.50 ft / 5.64 m
- Forecastle (20 %): 16.50 ft / 5.03 m
- Mid (50 %): 16.50 ft / 5.03 m (9.75 ft / 2.97 m aft of break)
- Quarterdeck (15 %): 9.75 ft / 2.97 m
- Stern: 9.75 ft / 2.97 m
- Average freeboard: 13.29 ft / 4.05 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 83.1 %
- Above water (accommodation/working, high = better): 150.2 %
Waterplane Area: 6,128 Square feet or 569 Square metres
Displacement factor (Displacement / loading): 171 %
Structure weight / hull surface area: 51 lbs/sq ft or 249 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 3.24
- Overall: 1.02
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
Good seaboat, rides out heavy weather easily

Changes:
- Replacement of the 130mm deck gun with British 4.5" DP single.
- Replacement of 57mm guns with Bofors 40mm.
- Re-engining with 1940 B+W diesels, and improvement of range.
- Installation of modern ASDIC and other electronics (probably not including radar)
- Renovation of internal spaces

Image originally by Wes/thesmilingassassin and modified by Brock (me).

Shannon-class, Irish Escort Frigate laid down 1937

Displacement:
1,100 t light; 1,162 t standard; 1,343 t normal; 1,487 t full load

Dimensions: Length overall / water x beam x draught
304.36 ft / 299.00 ft x 37.50 ft x 11.00 ft (normal load)
92.77 m / 91.14 m x 11.43 m x 3.35 m

Armament:
6 - 3.70" / 94.0 mm guns (3x2 guns), 25.33lbs / 11.49kg shells, 1937 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, majority forward, 1 raised mount - superfiring
4 - 1.57" / 40.0 mm guns (1x4 guns), 1.95lbs / 0.88kg shells, 1937 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
12 - 0.79" / 20.0 mm guns (6x2 guns), 0.24lbs / 0.11kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
4 - 0.50" / 12.7 mm guns (2x2 guns), 0.06lbs / 0.03kg shells, 1937 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 163 lbs / 74 kg
Shells per gun, main battery: 365

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.59" / 15 mm 0.59" / 15 mm
2nd: 0.59" / 15 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm - -
4th: 0.39" / 10 mm - -

- Conning tower: 0.98" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 6,982 shp / 5,209 Kw = 23.00 kts
Range 9,000nm at 12.00 kts
Bunker at max displacement = 325 tons

Complement:
110 - 144

Cost:
£0.451 million / $1.805 million

Distribution of weights at normal displacement:
Armament: 20 tons, 1.5 %
Armour: 15 tons, 1.1 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 12 tons, 0.9 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 194 tons, 14.4 %
Hull, fittings & equipment: 722 tons, 53.8 %
Fuel, ammunition & stores: 242 tons, 18.0 %
Miscellaneous weights: 150 tons, 11.2 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
3,526 lbs / 1,599 Kg = 139.2 x 3.7 " / 94 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.13
Metacentric height 1.5 ft / 0.4 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.33
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has low quarterdeck
and transom stern
Block coefficient: 0.381
Length to Beam Ratio: 7.97 : 1
'Natural speed' for length: 20.48 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 35
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: 20.00 ft / 6.10 m
- Forecastle (20 %): 18.00 ft / 5.49 m
- Mid (50 %): 17.00 ft / 5.18 m
- Quarterdeck (25 %): 10.00 ft / 3.05 m (17.00 ft / 5.18 m before break)
- Stern: 10.00 ft / 3.05 m
- Average freeboard: 15.76 ft / 4.80 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 73.1 %
- Above water (accommodation/working, high = better): 212.2 %
Waterplane Area: 7,096 Square feet or 659 Square metres
Displacement factor (Displacement / loading): 188 %
Structure weight / hull surface area: 56 lbs/sq ft or 274 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.85
- Longitudinal: 4.68
- Overall: 1.01
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

Breakdown of Miscellaneous Weights:
- 10 tons for hydrophones and ASDIC
- 40 tons for extra depth charge, K-guns, etc. (190x420lbs depth charges)
- 10 tons for K-guns
- 25 tons for radar
- 5 tons for Unspecified #2
- 50 tons for crew comfort or growth

Ships in Class:
- LÉ Shannon (F9) - built 1938
- LÉ Blackwater (F10) - laid down 1941
- LÉ Boyne (F11) - laid down 1941
- LÉ Liffey (F12) - laid down 1941

Notes:
In late 1943 and early 1944, the four Shannon-class ships were refitted with British radar.

Maeve class, Irish Ocean Patrol Ship laid down 1942
The patrol ship Maeve was designed to replace the preceding Deirdre class fisheries sloops, which were deemed to be too small for many of the tasks they undertook on the Atlantic. The Maeve was designed with a strong and weatherly hull suitable for service in the North Atlantic. Included in the design was salvage equipment and dedicated towing gear, useful for assisting disabled or distressed trawlers.

Displacement:
1,370 t light; 1,428 t standard; 2,194 t normal; 2,806 t full load

Dimensions: Length overall / water x beam x draught
244.88 ft / 238.00 ft x 34.50 ft x 18.70 ft (normal load)
74.64 m / 72.54 m x 10.52 m x 5.70 m

Armament:
2 - 3.70" / 94.0 mm guns in single mounts, 25.33lbs / 11.49kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline, all forward, 1 raised mount
2 - 1.57" / 40.0 mm guns (1x2 guns), 1.95lbs / 0.88kg shells, 1942 Model
Anti-aircraft guns in deck mount
on centreline aft
Weight of broadside 55 lbs / 25 kg
Shells per gun, main battery: 450

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm 1.00" / 25 mm
2nd: 1.00" / 25 mm - -

- Conning tower: 1.00" / 25 mm

Machinery:
Oil fired boilers, complex reciprocating steam engines,
Geared drive, 2 shafts, 4,986 ihp / 3,720 Kw = 18.00 kts
Range 7,000nm at 18.00 kts
Bunker at max displacement = 1,378 tons

Complement:
159 - 208

Cost:
£0.585 million / $2.339 million

Distribution of weights at normal displacement:
Armament: 7 tons, 0.3 %
Armour: 12 tons, 0.5 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 8 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 4 tons, 0.2 %
Machinery: 273 tons, 12.4 %
Hull, fittings & equipment: 728 tons, 33.2 %
Fuel, ammunition & stores: 823 tons, 37.5 %
Miscellaneous weights: 350 tons, 16.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
3,835 lbs / 1,739 Kg = 151.4 x 3.7 " / 94 mm shells or 1.3 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.2 ft / 0.4 m
Roll period: 13.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.11
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.500
Length to Beam Ratio: 6.90 : 1
'Natural speed' for length: 15.43 kts
Power going to wave formation at top speed: 55 %
Trim (Max stability = 0, Max steadiness = 100): 35
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.00 ft / 0.91 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.00 ft / 6.71 m
- Forecastle (20 %): 20.00 ft / 6.10 m
- Mid (55 %): 18.00 ft / 5.49 m (10.00 ft / 3.05 m aft of break)
- Quarterdeck (15 %): 10.00 ft / 3.05 m
- Stern: 10.00 ft / 3.05 m
- Average freeboard: 15.31 ft / 4.67 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 61.6 %
- Above water (accommodation/working, high = better): 97.3 %
Waterplane Area: 5,471 Square feet or 508 Square metres
Displacement factor (Displacement / loading): 228 %
Structure weight / hull surface area: 61 lbs/sq ft or 297 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.01
- Longitudinal: 7.56
- Overall: 1.23
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 Weight:
Not yet available.

Ships in Class:
- LÉ Maeve: laid down July 1942, completed June 1943
- LÉ Aisling - laid down January 1943, completed December 1943