Inconspicuous-class cruiser

### Retired

2 Post WWII (used as pier side training facilities and spare parts for two remaining active ships)

## General characteristics

### Displacement

10,000 t (11,200 short tons) (standard)12,861 t (14,177 short tons) (full load)

### Length

590 ft (180 m) (overall)574 ft (175 m) (waterline)

### Propulsion

4 shaft Parsons geared turbines8 Admiralty three-drum oil boilers

71,404 shp (53,245 kW)

### Range

10,000 nautical miles (18,520 km) at 15 knots (27 km)

### Armament

8 x 8 in/50 Mark VIII guns8 x 4 in/45 QF Mark V guns

16 x 2-pdr QF Mark VIII guns

6 x 21 inch torpedo tubes

### Armour

Waterline belt: 5 in (127 mm)Decks: 1.5 inch protected deck (40 mm) + 0.7 in (20 mm) bomb deck

Turrets: 6 in - 3 in (152 mm-76 mm)

Conning tower: 4 in (100 mm)

### Aircraft

4 x Armstrong Whitworth Atlas Mark I, later Supermarine Walrus Mark I

### Aircraft Facilities

1 x cross deck catapult

The ***Inconspicuous-class cruisers*** was a class of heavy cruisers built for the Royal Canadian Navy during the late 1920's. This was the first class of large warships specifically ordered and built for the Royal Canadian Navy, alongside the *Charybdis-class* cruisers. Designed within the limits of the Washington Naval Treaty of 1922, the class consisted of 4 ships. The four ships formed the back bone of the Royal Canadian Navy for many years, serving through World War II, the Korean War and into the Cold War with distinction.

## Background

During the World War I, the Royal Canadian Navy was tasked with protecting trade routes off the west coast of North America. Due to previous questionable investments, the ancient and under gunned HMCS *Rainbow* was left as the largest Allied ship in the theater. With the German raiders SMS *Leipzig* and SMS *Nurnberg* prowling the waters, *Rainbow* was hopelessly outmatched yet thankfully, missed the raiders by a single day off San Francisco.

In the interwar period, the Admiralty of the Royal Canadian Navy hoped to commission a class of cruisers to fulfill the role of trade protection and hunting of commerce raiders while also still being able to perform the duties of a front line fleet cruiser. Spurred on by the surplus of interest in the Naval service following the famous RMS *Olympic* accident, the project was funded by Parliament for a four strong class. Issuing a request for proposal in late 1926, a design was chosen and the ships were ordered to be built in Britain.

## Design

Sometimes incorrectly labeled as simply "Canadianized" versions of the *Kent* subclass due to their extremely similar dimensions and main battery armament, these ships were actually domestic designs which borrowed elements from the above mentioned ships. As commissioned, the Inconspicuous class differed from their *Kent* class cousins in their thinner pair of slanted funnels, cross deck catapult, cramped secondary battery and extremely raked bow design. Similar to the *Kent* class once again, they were excellent seaboats, being quite comfortable for their crews. The refits on the 1930's would lead to each ship having different superstructures which were the prototypes for the refits of *Warspite*, *Renown* and *London*.

The Royal Canadian Navy was very pleased with this design, as all ships survived through the vigorous service of the Second World War. Given the constant damage received by ships in the class and *Incalculable* specifically, the durability of these ships were only matched by the skill of Canadian damage control teams.

Even with the ships remembered fondly by their crew due to their handsome lines, crew members consistently argued among themselves which ship and it's refit was the sharpest looking. These arguments plateaued when all four ships were moored in Halifax shortly before the breakout of WWII, causing votes to be cast by the four ships crews, base personnel and the shipyard workers present. Following the announcement of the winner, a riot broke out pier side and had to be broken up by Military Police. The winner of the vote was lost to history and former crew members to this day all have differing claims to who won.

## Description

### Propulsion

Their engines were similar to the *Kent* class - four boilers in two boiler rooms providing steam for four Parsons geared turbines, generating 71,404 shaft horsepower. The design speed was 31 knots (57.4 km/h), half a knot slower than the *Kent* class. The operational range of these ships was 10,000 nmi at 15 knots. Below are the listed trial speeds of each ship.

*Inconspicuous* - 31.2 knots

*Inconceivable* - 31.5 knots

*Incomprehensible* - 31.3 knots

*Incalculable* - 31.7 knots

### Armament

The guns, BL 8-inch Mark VIII, were placed in superfiring twin turrets fore and aft. The turret design was needlessly complicated by the original requirement that they should be capable of anti-aircraft fire and were thus provided with a maximum elevation of 70°, despite the inability to train and elevate sufficiently quickly to track aerial targets and the complete lack of a suitable fire control system.

Secondary armament consisted of eight QF 4-inch Mark V guns in single mounts HA Mk.III fed from the amidships magazine. These were initially troublesome due to their cramped spacing. There were triple-tube torpedo launchers, one each side, amidships placed in a hull cut out. These were later removed due to sea spray interfering with the launching process. The single 4-inch Mk V guns were later replaced by Mk XVI guns in paired mountings during the 1930's refits.

Two quadruple mountings for the QF 2-pounder Mk.VIII anti-aircraft autocannon were placed centerline amidships. This class of cruisers was the first cruiser built by the Royal Navy to feature the cross deck catapult, which was lately extensively used in Royal Navy warship design. Four aircraft were carried, three in amidships hangers and one on the catapult itself.

### Protection

Unlike the *County* class, the *Inconspicuous* class was fitted with a traditional armor belt and deck armor layout. The horizontal protection consisted of an unsloped 127mm belt which covered the magazines and machinery. Vertical protection was a a 40mm protected deck with a 20mm bomb deck sitting above. The quarterdeck featured a 30mm armor plate for vertical protection, the barbettes and turrets ranged from 152mm to 76mm.

## Ships

### HMCS *Incalculable*

Birkenhead
 *Inconceivable* | Cammell Laird,
Birkenhead
 *Incomprehensible* | Harland and Wolff, Belfast
 *Incalcuable* | Harland and Wolff, Belfast
1930