Duncan Class Battleship (1901)
Armament
During the war, along with those of other older ships, the eight 6-inch guns casemated on the first deck proved of little use in practical sea states. It was decided to remove the eight casemate guns, plate their ports over and move 4 of them to the upper deck. Four of the twelve 12-pdr guns were also surrendered due to this alteration.[1]
Main Battery
The 12-in guns were Mark IX, mounted in B VI turrets.[2]
Secondary Battery
=Other Guns
Twelve 12-pdr guns, later reduced to eight when the 6-in casemate guns were relocated.
Torpedoes
Fire Control
The general system of wiring between the TSs in ships prior to Lord Nelson class is illustrated in Handbook for Fire Control Instruments, 1914.[3]
The equipment in Montagu is open to conjecture owing to her loss in 1906.
Rangefinders
Evershed Bearing Indicators
It is not known if this equipment was ever provided.
Directors
These ships never received directors for main or secondary batteries.[4]
Gunnery Control
The ship's guns were organized in 3 groups:[5]
- Two 12-in turrets
- Starboard 6-in guns ('A' & 'X')
- Port 6-in guns ('B' & 'Y')
Local Control in Turrets
There was no provision in these ships for local turret control wherein the receivers in the turret could be driven by transmitters in the officer's position at the back of the turret.[6]
Transmitting Stations
According to Frederic Charles Dreyer, Exmouth's Gunnery Officer in 1903, the ship at that stage had no TSes, no means of communicating ranges and deflections, and just a single 4.5-foot rangefinder. These innovations were maturing and seeing retrofits in the 2-3 years following.[7]
By 1914 at least, these ships had acquired fore and aft TSes.[8]
A C.O.S. allowed control options of
- Fore
- After
- Separate
Each control group had transmitters (of various type, see below) with a pair of receivers, one wired directly to the transmitter as a tell-tale, and the other fed off the wires going to the distant guns (i.e., the aft guns for the fore TS and vice-versa) as a repeat. "These repeat receivers are necessary to keep the idle transmitters in step; when changing back from separate control they are required to enable both halves of the group to be set alike before being paralleled on to one transmitter."[9]
Dreyer Table
These ships never received Dreyer tables.[10]
Fire Control Instruments
By 1909, the ships in this class fell into two or three categories for fire control instruments.
The simplest category is just Montagu, for which no information has been found.
The second group, Albemarle, Cornwallis and Duncan, was outfitted with Vickers, Son and Maxim instruments with Barr and Stroud rate instruments:[11]
- Vickers range transmitters: 6
- Vickers deflection transmitters: 6
- Vickers combined range and deflection receivers: 6
- Vickers C.O.S.: 3
- Vickers Check fire switches: 6
- Barr and Stroud rate transmitters: 4
- Barr and Stroud rate receivers: 8
- Siemens turret fire gongs: 8 with 2 keys
- Vickers fire gongs: 12 with 4 keys
- Captain's Cease Fire Bells: 18 with 1 key (supplier not stated)
Lastly, Exmouth and Russell were fitted with Barr and Stroud Mark II for range and rate, Mark I for orders, and Vickers for deflection:[12]
- Range (B. & S. Mark II): 6 transmitters (12 in Exmouth), 32 receivers
- Orders (B. & S. Mark I): 6 transmitters (12 in Exmouth), 22 receivers
- Rate (B. & S. Mark II): 4 transmitters, 8 receivers
- Deflection (Vickers): 6 transmitters (12 in Exmouth), 26 receivers (30 in Exmouth)
Additionally, this class had the following Siemens fire control equipment:[13]
- Group Switches: 3 (converted by Chatham)
- Turret fire gongs: 8 with 2 keys
- Fire Gongs: 12 (76 in Exmouth) with 4 keys
- Captain's Cease Fire Bells: 18 with 1 key
It appears that Exmouth's extraordinary number of instruments was because she found herself the proving ground for instruments.[Citation needed]
These ships lacked Target Visible and Gun Ready signals.[14]
Torpedo Control
See Also
Footnotes
- ↑ Technical History and Index Vol. 4, Part 36, p. 9.
- ↑ The Sight Manual, 1916, p. 109.
- ↑ Handbook for Fire Control Instruments, 1914, p. 50 & Plates 50 and 54(I).
- ↑ Director Firing Handbook, 1917, pp. 142-3.
- ↑ Handbook for Fire Control Instruments, 1914, p. 8.
- ↑ Handbook for Fire Control Instruments, 1914, p. 50.
- ↑ The Sea Heritage, p. 47.
- ↑ Handbook for Fire Control Instruments, 1914, p. 50 & Plates 50 and 54(I).
- ↑ Handbook for Fire Control Instruments, 1914, pp. 50-1.
- ↑ Handbook of Capt. F.C. Dreyer's Fire Control Tables, p. 3.
- ↑ Handbook for Fire Control Instruments, 1909, pp. 56-7, 60.
- ↑ Handbook for Fire Control Instruments, 1909, pp. 56-7, 59.
- ↑ Handbook for Fire Control Instruments, 1909, p. 59.
- ↑ Handbook for Fire Control Instruments, 1914, p. 11.
Bibliography
- Template:BibDreyerSeaHeritage
- Admiralty, Gunnery Branch (1910). Handbook for Fire Control Instruments, 1909. Copy No. 173 is Ja 345a at Admiralty Library, Portsmouth, United Kingdom.
- Admiralty, Gunnery Branch (1914). Handbook for Fire Control Instruments, 1914. G. 01627/14. C.B. 1030. Copy 1235 at The National Archives. ADM 186/191.
- Template:BibUKDirectorFiringHandbook1917
- Template:BibUKDreyerTableHandbook1918
