REFERENCE DOCUMENTS & RESOURCES - OFFICIAL ADMIRALTY DOCUMENTS
ADM 239/268: C.B.04039, ARMOUR PROTECTION (1939)
Updated 18-Oct-2007
This document is a modern transcription of Admiralty record ADM 239/268. It addresses armour protection of various Royal Navy and foreign ships. The original file is held at the The National Archives at Kew, London. This Crown Copyrighted material is reproduced here by kind permission of The National Archives.
START OF TRANSCRIPTION
CONTENTS
__________
Page |
|
| Introduction | |
| Table No. | |
| 1 Armour—British Ships | |
| 2 Armour—Foreign Ships | |
| 3 Range for Perforation of Deck Armour | |
| 4A Perforation Range for Thickness of Vertical Armour in inches—90° inclination | |
| 4B Perforation Range for Thickness of Vertical Armour in inches—60° inclination | |
| 5 British Capital Ships—Approximate Immunity Ranges to Chance Vital Hits in Magazines and Speed Hits in Machinery Spaces from Foreign Capital Ships' Gunfire | |
| 6 Foreign Capital Ships—Approximate Immunity Ranges to Chance Vital Hits in Magazines and Speed Hits in Machinery Spaces from British Capital Ships' Gunfire | |
| 7 British Cruisers—Approximate Immunity Ranges to Chance Vital Hits in Magazines and Speed Hits in Machinery Spaces from various Calibres of Guns | |
| 8 Foreign Cruisers—Approximate Immunity Ranges to Chance Vital Hits in Magazines and Speed Hits in Machinery Spaces from various Calibres of Guns | |
5
__________
This pamphlet is designed as a rough guide to the relative protection afforded by the armour of British and foreign capital ships and cruisers against gunfire from various calibres of guns.
The information contained herein should be treated with caution. It is based on the assumption that the penetrative power of foreign shells and the resistance of foreign armour to shell perforation are the same as the British. Calculations of the maximum or minimum ranges at which perforation of armour takes place have been based on the most recent information available at the time of publication of this pamphlet.
(ii) Knowledge of foreign armour is, in the case of certain countries, extremely scanty. In Table No. 2, which indicates the probable armour protection fitted in foreign ships, interrogation marks indicate that there is considerable doubt of the correctness of the figure given.
(iii) Tables Nos. 5 and 8 give the approximate immunity zones of British and foreign ships where both side armour and deck armour will defeat the shell. The upper limit of the immunity zone is the lowest range at which the shell, due to its comparatively steep angle of descent, can attack and penetrate the vertical or side armour.
The lower limit of the immunity zone is the maximum range at which the shell with its comparatively high remaining velocity can penetrate the vertical or side armour.
(iv) Under certain conditions a range is reached below which a shell, due to its flat trajectory, cannot theoretically reach the magazines although it may penetrate the side armour. This range is termed the "Shut down" range. This "shut down" effect disregards the fact that a shell may be deflected downwards due to its striking some obstruction after passing through the side armour.
(v) It must be emphasised that no real hard and fast line of demarcation can be drawn between what are immunity ranges and what are not. The theoretical angle of descent will obviously be compromised if the target is listed or rolling heavily. The inclination of the target to the line of fire will affect the range at which side armour can be penetrated. In addition, shell which theoretically should burst well inside a ship may be deflected or defeated by obstructions such as boats' davits, deck stiffeners, etc., which play no part in the theoretical armour protection.
(vi) In Tables Nos. 6 and 8 giving probable immunity zones for foreign ships, those zones based on uncertain thickness of armour from Table No. 2, are indicated by an interrogation mark.
6
ARMOUR
BRITISH FLEET
Class. |
Vertical. |
Horizontal. |
||||
Mag. |
E.R. |
B.R. |
Mag. |
E.R. |
B.R. |
|
| King George V | 15" |
14" |
14" |
6" |
5" |
5" |
| Nelson | 13"-14" |
13"-14" |
13"-14" |
6¾" |
4¼" |
4¼" |
| Warspite | 13" |
13" |
13" |
4¼" |
2¾" |
2¾" |
| Barham | 13" |
13" |
13" |
4¼" |
1" |
1" |
| Malaya | 13" |
13" |
13" |
4¼" |
2¾" |
1" |
| Royal Sovereign | 13" |
13" |
13" |
2" |
1" |
1" |
| Royal Oak | 13" |
13" |
13" |
4" |
2½" |
1" |
| Renown | 9" |
9" |
9" |
4" |
3" |
2½" |
| Repulse | 9" |
9" |
9" |
4½" |
3" |
1" |
| Hood | 12" |
12" |
12" |
3" |
2" |
2" |
| Kent | 4" |
4½" |
4½" |
2½" |
1 3/8" |
1 3/8" |
| London | 4" |
1" |
1" |
2½" |
1 3/8" |
1 3/8" |
| York | 4" |
3" |
3" |
2½" |
1½" |
1½" |
| Exeter | 5" |
3" |
3" |
2½" |
1½" |
1½" |
| Leander | 3½" |
3" |
3" |
2" |
1¼" |
1¼" |
| Arethusa | 3" |
2¼" |
2¼" |
2" |
1" |
1" |
| Southampton | 4½" |
4½" |
4½" |
2½" |
1¼" |
1¼" |
| Belfast | 4½" |
4½" |
4½" |
3" |
2" |
2" |
| Fiji | 3½" |
3¼" |
3¼" |
2" |
2" |
2" |
| Dido | 3" |
3" |
3" |
2" |
1" |
1" |
ARMOUR
FOREIGN SHIPS
Class. |
Vertical. |
Horizontal. |
||||
Mag. |
E.R. |
B.R. |
Mag. |
E.R. |
B.R. |
|
| French Fleet. | ||||||
| Lorraine | 10¾" |
10¾" |
10¾" |
1¾" |
1¾"+1¾" |
1¾"+1¾" |
| Bretagne (2) | 10¾" |
10¾" |
10¾" |
1¾" |
1¾"+1¾" |
1¾"+1¾" |
| Courbet (3) | 10¾" |
10¾" |
10¾" |
1¾"+1½" |
1¾"+1½" |
1¾"+1½" |
| Dunkerque (2) | 10.8"? |
10.8"? |
10.8"? |
3"? |
3"? |
3"? |
| Algerie | 4.3" |
4.3" |
4.3" |
3.1" |
3.1" |
3.1" |
| Suffren (4) | ? |
2.4"? |
2.4"? |
¾" |
¾" |
¾" |
| Duquesne (2) | — |
— |
— |
¾"? |
? |
? |
| La Galissionnaire (6) | 4" |
4" |
4" |
1½" |
1½" |
1½" |
| Emil Bertin | ? |
? |
? |
2"? |
? |
? |
| Jeanne D'Arc | — |
— |
— |
3"? |
? |
? |
| Duguay-Trouin (3) | — |
— |
— |
¾" |
½" |
½" |
| Com. Teste | 2" |
2" |
2" |
1½" |
1½" |
1½" |
| German Fleet. | ||||||
| Scharnhorst (2) | 8"?12.6" |
8"?12.6" |
8"?12.6" |
5.9" |
5.9" |
4" |
?7.8" |
?7.8" |
?7.8" |
||||
| Deutschland | 2 3/8"? |
2 3/8"? |
2 3/8"? |
2 3/8"? |
— |
— |
| Graf Spee (2) | 4" |
4" |
4" |
2¼"+4"? |
2¼"? |
2¼"? |
| Blucher (3) | 4" |
4" |
4" |
3¼" |
3¼" |
3¼" |
| Nurnberg | 3"? |
3"? |
3"? |
1" |
1" |
1" |
| Leipzig | 4" |
4" |
4" |
1 3/8" |
1 3/8" |
1" |
| Köln (3) | 3"? |
3"? |
3"? |
2"? |
2"? |
? |
| Emden | 4" |
4" |
3" |
? |
? |
? |
7
TABLE No. 2—continued
ARMOUR—continued
FOREIGN SHIPS—continued
Class. |
Vertical. |
Horizontal. |
||||
Mag. |
E.R. |
B.R. |
Mag. |
E.R. |
B.R. |
|
| Italian Fleet. | ||||||
| Littorio | ? |
? |
? |
? |
? |
? |
| Duilio (2) | ? |
? |
? |
? |
? |
? |
| Cavour (2) | 9¾" |
9¾" |
9¾" |
3" |
? |
? |
| Zara (3) | 6" |
6" |
6" |
2¾" |
2¾" |
— |
| Gorizia | 8¼" |
9 7/16" |
9 7/16" |
2½" |
2½" |
— |
| Bolzano | 2¾"? |
2¾"? |
2¾"? |
2" |
2" |
2" |
| Trento (2) | 3"? |
2¾"? |
2¾"? |
2" |
2" |
2" |
| Abruzzi (2) | 6"? |
3"? |
3"? |
1½"? |
1½"? |
1½"? |
| Montecuccoli (2) | — |
— |
— |
— |
1½"? |
— |
| D'Aosta (2) | 4¾"? |
4¾"? |
4¾"? |
— |
— |
— |
| Diaz (2) | 1¼" |
1¼" |
1¼" |
1 5/8" |
¾" |
¾" |
| Guissano (4) | 1.6"? |
1.6"? |
1.6"? |
1" |
1" |
1" |
| Japanese Fleet. | ||||||
| Nagato (2) | 14" |
14" |
14" |
7" |
? |
? |
| Ise (2) | 12" |
12" |
12" |
4"? |
2" |
2" |
| Fuso (2) | 12" |
12" |
12" |
4"? |
2" |
2" |
| Kongo (3) | 8" |
8" |
8" |
3"? |
(4"-5")? |
3" |
| Takao (4) | 4"? |
3"? |
3"? |
5" |
— |
— |
| Nachi (4) | 4"? |
3"? |
3"? |
5" |
— |
3" |
| Mogami (4) | 2½" |
2½" |
2½" |
2" |
— |
— |
| Furutaka (2) | 1"? |
3" |
3" |
2"? |
? |
? |
| Aoba (2) | 1"? |
3" |
3" |
2"? |
? |
? |
Details of other Cruisers not known. |
||||||
| Spanish Fleet. | ||||||
| Canarias (1) | 4" |
1½" |
1½" |
2" |
1¼" |
1¼" |
| Almirante Cervera (3) | 2"? |
3"? |
3"? |
1" |
1½" |
1½" |
| U.S.A. Fleet. | ||||||
| Colorado (3) | 13½" |
13½" |
13½" |
3½"+1½"? |
3½"+1½"? |
3½"+1½"? |
| California (2) | 13½" |
13½" |
13½" |
3"? |
3"? |
3"? |
| New Mexico (8) | 13½" |
13½" |
13½" |
5½" |
5½" |
5½" |
| Arizona (2) | 13½" |
13½" |
13½" |
5"? |
5"? |
5"? |
| Nevada (2) | 13½" |
13½" |
13½" |
5" |
5" |
5" |
| Texas (2) | 11" |
11" |
11" |
5"? |
2" |
2" |
| Arkansas | 11" |
11" |
11" |
2"? |
2"? |
2"? |
| Quincey (2) | 5"? |
5"? |
5"? |
3"+2"? |
? |
? |
| New Orleans | 5" |
5" |
5" |
3"? |
3"? |
3"? |
| Portland (2) | 4½" |
4½" |
4½" |
? |
2½" |
2½" |
| Augusta (6) | 3"? |
3"? |
3"? |
2"+1"? |
? |
? |
| Pensacola (2) | 2½"? |
2½"? |
2½"? |
2"? |
2"? |
2"? |
| Philadelphia (9) | 4" |
5"? |
5"? |
2" |
3"? |
3"? |
| Omaha (10) | ? |
3" |
3" |
? |
1½" |
1½" |
Notes
(1) The number in brackets after the class name of ships indicates the number of ships in that class with approximately the same armour protection.
(2) A question mark against a figure denotring thickness of armour indicates doubt of the correctness of the figure given.
8
RANGE FOR PERFORATION OF DECK ARMOUR
Diameter and Weight of Shell |
Thickness of Deck in inches. |
||||||
1" |
2" |
3" |
4" |
5" |
6" |
7" |
|
| 16"—2,375 lb. | — |
14,500 |
19,500 |
23,500 |
27,500 |
30,500 |
33,500 |
| 16"—2,048 lb. | — |
15,000 |
20,750 |
25,500 |
29,500 |
33,250 |
36,500 |
| 15"—1,938 lb. | — |
14,250 |
19,500 |
24,000 |
27,500 |
31,000 |
34,000 |
| 15"—1,920 lb. | — |
14,250 |
19,250 |
23,250 |
26,500 |
29,750 |
32,500 |
| 14"—1,590 lb. | — |
15,000 |
20,500 |
25,000 |
29,000 |
32,250 |
35,500 |
| 14"—1,400 lb. (American H.V.) | — |
18,500 |
24,000 |
28,500 |
32,500 |
36,000 |
— |
| 13.6"—1,168 lb. (French) | 15,000 |
22,500 |
27,500 |
32,000 |
35,500 |
— |
— |
| 12"—850 lb. | 11,500 |
19,000 |
25,000 |
30,000 |
34,000 |
— |
— |
| 11"—661 lb. (German) | 16,000 |
23,000 |
28,500 |
33,000 |
— |
— |
— |
| 9.2"—380 lb. (Coast Defense) | 12,000 |
21,500 |
— |
— |
— |
— |
— |
| 8"—256 lb. | 14,000 |
21,000 |
26,500 |
— |
— |
— |
— |
| 6.1"—124 lb. (French) | 17,000 |
23,500 |
— |
— |
— |
— |
— |
| 6"—112 lb. | 14,500 |
22,000 |
— |
— |
— |
— |
— |
| 6"—100 lb. | 15,750 |
23,000 |
— |
— |
— |
— |
— |
| 5.9"—103.6 lb. (German) | 17,500 |
27,000 |
— |
— |
— |
— |
— |
1" |
1½" |
2" |
|||||
| 5.25"—80 lb. | 16,000 |
20,000 |
— |
||||
| 4.7"—62 lb. | 16,000 |
— |
— |
||||
9
PERFORATION RANGE FOR THICKNESS OF VERTICAL ARMOUR IN INCHES
90° Inclination. |
||||||||||
N.C. |
C. |
|||||||||
| Gun. Shell. | 2½" |
3" |
4" |
4½" |
6" |
8" |
10" |
12" |
14" |
16" |
| 16" 2,375 lb. | — |
— |
— |
— |
— |
— |
— |
28,000 |
22,250 |
18,000 |
| 16" 2,048 " | — |
— |
— |
— |
— |
— |
26,000 |
20,500 |
16,000 |
12,000 |
| 15" 1,938 " | — |
— |
— |
— |
— |
— |
26,000 |
19,500 |
15,000 |
11,000 |
| 15" 1,920 " | — |
— |
— |
— |
— |
— |
20,000 |
16,000 |
12,000 |
9,000 |
| 14" 1,590 " | — |
— |
— |
— |
— |
— |
25,000 |
19,500 |
14,500 |
— |
| 14" U.S.A. ( H.V.) | — |
— |
— |
— |
— |
— |
22,000 |
17,250 |
13,500 |
— |
| 13.6" French | — |
— |
— |
— |
— |
— |
21,000 |
17,500 |
14,000 |
— |
| 12" 850 lb. | — |
— |
— |
— |
— |
15,000 |
11,500 |
8,500 |
— |
— |
| 11" German | — |
— |
— |
— |
26,500 |
20,000 |
16,000 |
13,000 |
— |
— |
| 9.2" Coast Defense | — |
— |
— |
21,000 |
16,000 |
11,000 |
— |
— |
— |
— |
| 8" 256 lb. | — |
28,000 |
21,000 |
17,000 |
13,000 |
9,000 |
— |
— |
— |
— |
| 6.1" French | 21,500 |
18,500 |
13,500 |
10,000* |
— |
— |
— |
— |
— |
— |
| 6" 112 lb. | 18,000 |
14,500 |
10,500 |
7,000* |
— |
— |
— |
— |
— |
— |
| 5.9" German | 20,000 |
17,000 |
13,500 |
9,000* |
— |
— |
— |
— |
— |
— |
| 5.25" 80 lb. | 13,000 |
11,250 |
8,000* |
— |
— |
— |
— |
— |
— |
— |
| 4.7" 62 " | 11,500 |
9,500 |
7,000* |
— |
— |
— |
— |
— |
— |
— |
| 4.7" 50" | 6,500 |
5,250 |
— |
— |
— |
— |
— |
— |
— |
— |
| 4.5" 55" | 11,500 |
8,500 |
— |
— |
— |
— |
— |
— |
— |
— |
* Although perforation is to be expected at these ranges, correct detonation is improbable and only minor damage will result. Blank spaces in the top left-hand corner of each table indicate that the shell will defeat the armour even at its maximum range. Blank spaces at the bottom right-hand side of the tables indicate that the shell can never perforate the armour.
10
PERFORATION RANGE FOR THICKNESS OF VERTICAL ARMOUR IN INCHES—continued
90° Inclination. |
||||||||||
N.C. |
C. |
|||||||||
| Gun. Shell. | 2½" |
3" |
4" |
4½" |
6" |
8" |
10" |
12" |
14" |
16" |
| 16" 2,375 lb. | — |
— |
— |
— |
— |
— |
29,000 |
23,000 |
18,000 |
13,500 |
| 16" 2,048 " | — |
— |
— |
— |
— |
— |
21,500 |
16,500 |
12,000 |
8,000 |
| 15" 1,938 " | — |
— |
— |
— |
— |
— |
21,000 |
15,000 |
11,000 |
— |
| 15" 1,920 " | — |
— |
— |
— |
— |
— |
16,500 |
12,500 |
9,000 |
— |
| 14" 1,590 " | — |
— |
— |
— |
— |
— |
20,000 |
15,500 |
10,500 |
— |
| 14" U.S.A. ( H.V.) | — |
— |
— |
— |
— |
— |
18,500 |
14,000 |
10,000 |
— |
| 13.6" French | — |
— |
— |
— |
— |
— |
18,000 |
14,500 |
11,500 |
— |
| 12" 850 lb. | — |
— |
— |
— |
— |
13,000 |
9,000 |
6,000 |
— |
— |
| 11" German | — |
— |
— |
— |
23,000 |
18,000 |
14,000 |
10,500 |
— |
— |
| 9.2" Coast Defense | — |
— |
— |
18,000 |
13,500 |
9,000 |
— |
— |
— |
— |
| 8" 256 lb. | — |
24,500 |
18,000 |
15,000 |
11,000 |
7,000 |
— |
— |
— |
— |
| 6.1" French | 18,500 |
16,000 |
11,500 |
— |
— |
— |
— |
— |
— |
— |
| 6" 112 lb. | 16,000 |
12,500 |
9,000 |
5,500* |
— |
— |
— |
— |
— |
— |
| 5.9" German | 17,000 |
15,000 |
12,000 |
— |
— |
— |
— |
— |
— |
— |
| 5.25" 80 lb. | 12,000 |
9,500 |
6,500* |
— |
— |
— |
— |
— |
— |
— |
| 4.7" 62 " | 10,000 |
8,000 |
— |
— |
— |
— |
— |
— |
— |
— |
| 4.7" 50" | 5,500 |
4,500 |
— |
— |
— |
— |
— |
— |
— |
— |
| 4.5" 55" | 9,500 |
7,000 |
— |
— |
— |
— |
— |
— |
— |
— |
* Although perforation is to be expected at these ranges, correct detonation is improbable and only minor damage will result. Blank spaces in the top left-hand corner of each table indicate that the shell will defeat the armour even at its maximum range. Blank spaces at the bottom right-hand side of the tables indicate that the shell can never perforate the armour.
11
BRITISH CAPITAL SHIPS—APPROXIMATE IMMUNITY RANGES TO CHANCE VITAL HITS IN MAGAZINES AND SPEED HITS IN MACHINERY SPACES FROM FOREIGN CAPITAL SHIPS' GUNFIRE
90° Inclination
1 |
2 |
3 |
4 |
5 |
6 |
7 |
||||||
Britsh, under fire from |
16" (Japan, U.S.A.) |
15" (Germany, Italy, France) |
14" Medium Velocity |
14" High Velocity (U.S.A.) |
12.6" (Italy) |
11" (Germany) |
||||||
Class. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
| King George V (5) | 14-33 |
16-30 |
13-31 |
15-27 |
0-32 |
14-29 |
0-36 |
14-32 |
Immune |
0-34 |
Immune |
Immune |
| Nelson (2) | 16-35 |
16-26 |
15-33 |
15-25 |
15-35 |
15-27 |
14-up |
14-29 |
Immune |
0-31 |
Immune |
0-33 |
| Royal Sovereign (4) | 0 |
0 |
0 |
0 |
0 |
0 |
15-18 |
0 |
0-19 |
0-11 |
0-23 |
0-16 |
| Royal Oak (1) | 18-25 |
0 |
17-24 |
0 |
17-25 |
0 |
15-28 |
0 |
0-30 |
0-11 |
0-33 |
0-16 |
| Warspite (3) | 18-26 |
18-19 |
17-25 |
17-18 |
17-26 |
17-19 |
15-29 |
15-22 |
0-31 |
0-24 |
0-33 |
0-27 |
| Barham (1) | 18-26 |
0 |
17-25 |
0 |
17-26 |
0 |
15-29 |
0 |
0-31 |
0-12 |
0-33 |
0-16 |
| Malaya (1) | 18-26 |
0 |
17-25 |
0 |
17-26 |
0 |
15-29 |
0 |
0-31 |
0-12 |
0-33 |
0-16 |
| Hood (1) | 0 |
0 |
0 |
0 |
19-20 |
0 |
17-24 |
17-18 |
9-25 |
9-19 |
13-28 |
13-23 |
| Renown (1) | 0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
13-30 |
13-22 |
18-33 |
18-25 |
| Repulse (1) | 0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
13-32 |
0 |
18-up |
0 |
Notes
(1) Figures are given in thousands of yards.
(2) The "shut down"* range for all ships is of the order of 12,000 yards at 90° inclination, and decreases as the inclination narrows.
(3)
The perforation range for vertical armour decreases as the inclination narrows, thereby giving a broadening of the immunity zones.
*See Introduction, para. (iv)
12
FOREIGN CAPITAL SHIPS—APPROXIMATE IMMUNITY RANGES TO CHANCE VITAL HITS IN MAGAZINES AND SPEED HITS IN MACHINERY SPACES FROM BRITISH CAPITAL SHIPS' GUNFIRE
90° Inclination
1 |
2 |
3 |
4 |
5 |
|||||
Country and Class. |
16" (Nelson's). |
Old—15" (All 15" ships except those in column 4) |
New—15" |
14" (King George V's). |
|||||
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
||
| France. | |||||||||
| Richelieu (2) | — |
—
|
—
|
—
|
—
|
—
|
—
|
—
|
|
| Bretagne (2) | None |
None |
None |
18-19 |
None |
None |
None |
None |
|
| Lorraine (1) | None |
None |
None |
None |
None |
None |
None |
None |
|
| Courbet (2) | None |
None |
18-19 |
18-19 |
None |
None |
None |
None |
|
| Dunkerque (2) | None |
None |
18-19 |
18-19 |
None |
None |
None |
None |
|
| Germany. | |||||||||
| Tirpitz (2) | — |
—
|
—
|
—
|
—
|
—
|
—
|
—
|
|
| Scharnhorst (2) | 19-33 |
19-25 |
15-30 |
15-23 |
18-31 |
18-24 |
18-32 |
18-25 |
|
| Deutschland (2) Graf Spee (1) |
} | None |
None |
None |
None |
None |
None |
None |
None |
| Italy. | |||||||||
| Littoria (2) | ? |
? |
? |
? |
? |
? |
? |
? |
|
| Duilio (2) | ? |
? |
? |
? |
? |
? |
? |
? |
|
| Cavour (2) | 26-? |
26-? |
20-? |
20-? |
26-? |
26-? |
24-? |
24-? |
|
| Japan. | |||||||||
| Nagato (2) | 16-36 |
16-? |
12-32 |
12-? |
15-34 |
15-? |
14-35 |
14-? |
|
| Ise, Fuso (4) | 20-25 |
None |
16-23 |
None |
19-25 |
None |
19-25 |
None |
|
| Kongo (3) | None |
None |
None |
None |
None |
None |
None |
None |
|
| U.S.A. | |||||||||
| Colorado (3) | 17-25 |
17-25 |
13-23 |
13-23 |
16-24 |
16-24 |
16-25 |
16-25 |
|
| Tennessee (2) | 17-21 |
17-21 |
13-19 |
13-19 |
16-19 |
16-19 |
16-20 |
16-20 |
|
| New Mexico | } (7) |
17-29 |
17-29 |
13-26 |
13-26 |
16-27 |
16-27 |
16-29 |
16-29 |
| Pennsylvania | |||||||||
| Nevada | |||||||||
| Texas (2) | None |
None |
None |
None |
None |
None |
None |
None |
|
Notes
(1) Figures are given in thousands of yards.
(2) Numbers in brackets after the class name of ships indicates number of ships in that class .
(3) Interrogation marks indicate doubt or lack of knowledge of armour thickness upon which immunity ranges are based
(4) The "perforation" range for vertical armour decreases as the inclination narrows, thereby giving a broadening of the immunity zones.
13
BRITISH CRUISERS—APPROXIMATE IMMUNITY RANGES TO CHANCE VITAL HITS IN MAGAZINES AND SPEED HITS IN MACHINERY SPACES FROM VARIOUS CALIBRES OF GUNS
90° Inclination
Britsh, under fire from |
8" |
6.1" (French) |
6" |
5.9" (German). |
5.25" (80 lb. Proj.). |
4.7" (62 lb. Proj.). |
||||||
Class. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
C.V.H. |
Speed. |
| Kent | 21-23.5 |
17-18 |
Above 13.5 |
10-20 |
Above 10.5 |
7-18 |
Above 13.5 |
9-22 |
Above 8 |
Below 20 |
Above 11.5 |
Immune |
| London | 21-23.5 |
None |
Above 13.5 |
None |
Above 10.5 |
None |
Above 13.5 |
None |
Above 8 |
None |
Above 11.5 |
None |
| York | 21-23.5 |
None |
Above 13.5 |
18.5-20 |
Above 10.5 |
14.5-18 |
Above 13.5 |
17-22 |
Above 8 |
11.25-20 |
Above 11.5 |
Above 9.5 |
| Exeter | 16-23.5 |
None |
Immune |
18.5-20 |
Immune |
14.5-18 |
Immune |
17-22 |
Immune |
11.25-20 |
Immune |
Above 9.5 |
| Leander | None |
None |
16-23.5 |
None |
12.5-22 |
None |
15-27 |
17-20 |
Above 10 |
11.25-16 |
Above 8.5 |
9.5-16 |
| Arethusa | None |
None |
18.5-23.5 |
None |
14.5-22 |
None |
17-27 |
None |
Above 11.25 |
15-16 |
Above 9.5 |
13-16 |
| Southampton | 17-24 |
None |
Above 10 |
10-17 |
7-22 |
7-16 |
Above 9 |
9-20 |
Immune |
Below 16 |
Immune |
Below 16 |
| Belfast | 17-26.5 |
17-21 |
Above 10 |
10-23.5 |
Above 7 |
7-22 |
Above 9 |
9-27 |
Immune |
Immune |
Immune |
Immune |
| Fiji | None |
None |
16-23.5 |
17.5-23.5 |
12.5-22 |
13.5-14.5 |
15-27 |
16-27 |
Above 15 |
Above 10.5 |
Above 8.5 |
Above 9 |
| Dido | None |
None |
18.5-23.5 |
None |
14.5-22 |
None |
17-27 |
None |
Above 11.25 |
11.25-16 |
Above 9.5 |
|