Chatham Class Cruiser (1911)
The six light cruisers of the Chatham Class (sometimes called the Chatham subclass of the Town Class) were completed between 1912 and 1916.
Armament
Guns
Torpedoes
The ships had two 21-in submerged broadside tubes forward depressed 2 degrees with the axis of the tube 1 foot 5.25 inches above the deck.[1]
Fire Control
Rangefinders
Evershed Bearing Indicators
This equipment was unlikely to have been fitted for gun or searchlight control.[2]
Gunnery Control
Control Positions
Control Groups
Directors
In 1916, it was approved that the ships of this class should be retrofitted with directors as time, resources and opportunity permitted.[3]
All ships except Brisbane (owing to her service in the Pacific) were fitted with directors in 1917 and 1918.[4]
Torpedo Control
Transmitting Stations
Dreyer Table
These ships had no fire control tables.[5]
Fire Control Instruments
For some reason, this class is not listed in Appendix I of Handbook for Fire Control Instruments, 1914, but I would suppose that the next paragraph applies to Chatham as it did to the Weymouth class that preceded it, but that the Mark III supposition is more plausible.
The four ships in this class were likely completed with the latest Vickers Mark III F.T.P. Fire Control Instruments[6] in the manner of the Weymouth as follows:[7][8]
- Range Transmitters: 2 (P & S)
- Deflection Transmitters: 2 (P & S)
- Range Receivers: 8
- Deflection Receivers: 8
- C.O.S.: none
- Vickers Fire Gongs: 8 with 2 keys
By 1915, a 4-way C.O.S. had been added to permit some freedom in assigning the CL guns to either broadside group:[9]
- both on port
- both on starboard
- fore on port, aft on starboard
- aft on port, fore on starboard
In addition, navyphones addressing telaupads at the guns supported a finer control by breaking each broadside down into 2 groups, fore and aft. 3-way change-over (fore, after, separate) switches dictated which navyphones addressed which guns. The aft navyphones were in the aft control platform. The fore navyphones could be either in the fore control platform or plugged in in the TS.[10]
The CL guns can be joined to either broadside battery by 2-way switches located in the TS and the control platforms (when the control platform switches are used, the TS switches are left "off". In the other case, plugs were removed at the control platform switches).[11]
See Also
Footnotes
- ↑ Addenda (1911) to Torpedo Manual, Vol. III., 1909, p. 155.
- ↑ The Technical History and Index: Fire Control in HM Ships, 1919, p. 29.
- ↑ Annual Report of the Torpedo School, 1916, p. 175.
- ↑ The Technical History and Index: Fire Control in HM Ships, 1919, pp. 11-12.
- ↑ absent from list in Handbook of Capt. F.C. Dreyer's Fire Control Tables, p. 3.
- ↑ Annual Report of the Torpedo School, 1910, p. 148.
- ↑ Handbook for Fire Control Instruments, 1909, pp. 57, 60.
- ↑ Handbook for Fire Control Instruments, 1914, p. 65.
- ↑ Handbook for Fire Control Instruments, 1914, p. 65.
- ↑ I'm not 1000% sure I understand this description, either.
- ↑ Handbook for Fire Control Instruments, 1914, p. 65.
Bibliography
- 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:BibUKDreyerTableHandbook1918
- Template:BibUKFireControlInHMShips1919