Battlecruisers of WW1(ish)
Indefatigable class
Built to a heavier, more capable standard, as was suggested in OTL. Basically, a slightly improved Von der Tann in armament layout and armour, mounting 8 x 12” guns and easily surpassing their designed speed of 25 knots in trials.
The first is laid down in 1909. That year, an Imperial Conference is held, at which Australia and New Zealand agree to pay for the purchase of two more ships. India, South Africa, and Canada also express interest. Canada and South Africa will later decide not to participate, with South Africa instead sponsoring Cruisers and Canada a later Agincourt Class battlecruiser. India will eventually settle on a single Indefatigable in late 1910 after determining that the Lion would be more difficult to maintain. The Royal Navy encourages this as it would allow the three ships in the Indian and South Pacific to work as a homogenous unit.
Lion Class
Even as the Indefatigable Class was being finalized First Sea Lord Jackie Fisher had introduced a design that he called the Nonpareil. Mounting 8 x 13.5” guns in an A,B.X,Y arrangement, all on the centre line and utilizing only oil fuel and small tube boilers to achieve 28 knots on 22,500 tons, it was an ambitious design. In some ways, too ambitious.
The rest of the Admiralty Board had serious reservations about the technical risks of such a vessel. From the back and forth a design emerged for the 1910 battlecruiser (Named the Lion Class). Fisher had succeeded in getting the increased speed of 28 knots and the 13.5” armament accepted. However, coal firing with sprayed oil and large tube boilers were maintained at the insistence of the Engineer in Chief. The fight over number of guns (several members of the board had preferred 10) had led to the Lion having a Q turret but losing X turret. Fishers influence had been sufficient to move the “Q” turret astern considerably while moving the engine and boilers rooms (and their associated funnels) ahead. This kept the firing angles of “Q” turret open and in theory allowed for both turrets to be fired aft. It was designed for 28 knots on 70,000 shp. In trials, they would make 76,000 shp but would only manage 27.5 knots speed. It was originally intended to build only one battlecruiser in the 1909-1910 estimates but the infamous “We want eight and we won’t wait!” campaign changed priorities and allowed a second Lion class to be laid down in the same year. Both ships would commission into the fleet in 1912.
Tiger Class
The increased building program in 1910 presented Fisher with an opportunity. Despite getting some of what he wanted out of the Lion design, he was unsatisfied with the compromises he had been forced to make. With the increased building program, Fisher was able to convince the board to build one of the battlecruisers to a modified design incorporating oil firing and small tube boilers. This ship, known as HMS Tiger, would help to ease the resistance to the new machinery considerably. Completing slightly smaller and on a lower displacement than the Lion class, Tiger had increased protection over her half-sisters while still having a design speed half a knot faster (which she would exceed, making 29 knots in trials). She would also be almost 100,000 pounds cheaper to construct. That the board was convinced is evidenced by the fact that they would lay down another of the class, with minor changes, in the 1911 building year. The second Tiger class would commission in 1913.
Leopard Class
In 1911 Fisher retired from the Admiralty, following the prescriptions of the 1870 Order in Council (mandated retirement for Admirals of the Fleet was 70 years old). It is somewhat ironic then, that he was able to achieve from retirement what he had failed to do as First Sea Lord. Namely, the construction of his Nonpareil concept. In truth Fisher had little to do with the final decision, but his work in previous years had certainly laid the groundwork.
The Leopard class laid down in 1912 would, at its heart, be the Nonpareil concept, slightly updated. Mounting 8 x 13.5” guns in two super firing pairs fore and aft, and using small tube, oil fired boilers she was designed for 30 knots and would make an extra half a knot in trials. It was thought that the nature of the addition of geared turbines during construction kept her from reaching her full potential. The second ship of the class (laid down 1913) would have geared turbines designed in from the start and would make 32 knots on trial. They would be the first ships in the Royal Navy to use the all-or-nothing armour scheme since the advent of QF guns in the late 19th century, and was able to increase protection to a uniform 10” over machinery and magazine spaces.
As impressive as the class is it is its accomplishment is sometimes overshadowed by the fact that they were laid down in the same years as the Queen Elizabeth and Revenge classes, which are sometimes referred to as Battlecruisers. Though they still maintained a speed advantage over their contemporaries it had been narrowed considerably, leading some to question the ships purpose.
Renown Class
The Renown class was never built. They were a design study initiated by Fisher upon his return to the Admiralty in 1914. With the Queen Elizabeth and Agincourt Classes due to complete soon, Fisher was concerned that if a 28-knot battleline became a reality the fleet scouting roll would be vacant. He commissioned a study on the viability of completing some of the Revenge class to a different design, capable of 34-35 knots. The resulting design was considered possible but would require significant sacrifices in protection.
Fisher considered this a worthwhile trade but the increased cost of the design over the Revenge class and the belief in Cabinet that the war would be short kept the extra expenditure from being allocated. It didn’t help that the Revenges were supposed to be a limited peace offering to those members of the Admiralty that were still uncomfortable with the 28-knot speed of the Queen Elizabeth class. A status that Fisher had already undermined by determining that they would be oil firing. Turning them into 35 knot light battlecruisers was a step too far. Later in the war, when the idea of a Battlecruiser for the emerging fast battle line came up, Fisher would state that he now believed that the emerging aircraft carrier would become the scouting force for the battle line in the future.