Chatham 1913
| Name | No | Yard No | Builder | Laid down | Launched | Comp | Fate |
| Chatham | 37, 38, 18 | Chatham DYd, UK | 3.1.1911 | 9.11.1911 | 12.1912 | sold for BU 7.1926 |
|
Displacement normal, t |
5400 |
|
Displacement full, t |
6000 |
|
Length, m |
139.6 |
|
Breadth, m |
14.9 |
|
Draught, m |
4.90 |
|
No of shafts |
4 |
|
Machinery |
4 Parsons steam turbines, 12 Yarrow boilers |
|
Power, h. p. |
25000 |
|
Max speed, kts |
25.5 |
|
Fuel, t |
coal 1240 + oil 260 |
| Endurance, nm(kts) | 4500(16) |
| Armour, mm |
belt: 51 on 25mm plating, deck: 38 - 10, CT: 102, gun shields: 102 |
|
Armament |
8 x 1 - 152/50 BL Mk XI, 4 x 1 - 47/40 3pdr Hotchkiss Mk I, 2 - 533 TT (beam, sub) |
|
Complement |
475 |
Project history: In the three cruisers
authorised for 1911 the weaknesses of the preceding classes were eliminated. On
virtually the same dimensions seakeeping was improved by extending the
forecastle aft for more than two-thirds of the length, and some side protection
was worked in, all at the cost of only a slight increase in beam. A reduction in
metacentric height also reduced rolling and improved shooting. The protective
deck of the Bristol and Weymouth designs was retained, but only to
maintain watertight integrity (10mm over most of its length, 19mm over machinery
and 38mm over the steering gear). A shell penetrating this deck would still have
to penetrate three decks first, and would probably have detonated by the time it
reached the so-called 'splinter deck'. The weight saved on deck plating was
devoted to a 51mm waterline belt of nickel steel on 25mm shell plating. The
protection thus became part of the main structure of the ship, enabling weight
to be saved on framing. As this arrangement of double plating could not be given
a double curvature the midships section in the new design was slab-sided. There
had been dissatisfaction with the high-velocity Mk.XI 152mm gun, and so the new
cruisers had to be reverted to a RGF-designed 45cal lower-velocity gun, the Mk
XII. It had the advantage of shooting more accurately and being nearly 2t
lighter, with virtually the same range (12,700m), but only cruisers of 1912
Programme (Birmingham class) received new guns.
The Chatham class could easily be distinguished from
the Weymouths by their long forecastle deck and the 'plough' bow.
Protection: Armoured belt protected ship at full
length, its thickness was 76mm (summary) abreast machinery spaces and 51mm at ship ends.
It extended to main deck (and to upper deck abreast machinery). Protective deck
was 19mm thick over machinery and 38mm over steering gear. Its thickness over
other ship parts was 10mm.
Modernizations: 1915: + 1 x 1 - 76/45 20cwt QF Mk I
Naval service: No significant events.
© Ivan Gogin, 2015