In the aftermath of Dogger Bank on 24 January 1915, the British decided to improve rate of fire and the quality of their shells despite the British and German explosions at Dogger Bank. The information got passed to Germany and ended up being used to improve the quality of shells for fighting at Jutland, but it was too late to stop improving the quality of shells for Germany and Britain. The Germans decided to respond to the shortage of battlecruisers by completing Salamis as SMS Salamis with the guns of Heligoland installed on it and decommissioned the armoured cruiser Furst Bismarck's guns to reinforce Heligoland. The armoured cruiser Roon would also replace Moltke and Hindenburg would replace Derrflinger. The British sped up completion of the Renown and Courageous-class battlecruisers to replace the battlecruiser losses at Dogger Bank and HMS Inflexible's loss at the Dardanelles Campaign.
Just as the battle between the battlecruisers began to start the Battle of Jutland on 31 July 1916 (delayed by 2 months for the Salamis's completion), catastrophe struck the British. At 3:54 p.m., an 8 inch shell from Roon made its way into HMS Renown and the impact initially tore a gigantic hole that reached the 6 inch guns, igniting charges. Then, the base of the shell went through the 1in armour deck and penetrated the 0.75in web of the main steam pipe, and the armour deck was also holed by another fragment. The after 6in magazine was flooded together with Q port magazine, but could not be achieved in time and blew up when fires from the X barbette hit also became serious and combined, ripping the magazines and ship apart.
At approximately 4:00 p.m., a shell from Lutzow detonated on HMS Repulse's Q Turret. The explosion was louder than expected and with everybody dead on impact and fires spreading from exploded cordite and lack of response, by 4:28 P.M., the Repulse had detonated with the loss of Admiral Beatty (who survived losing Lion and the sunken Derrflinger at Dogger Bank) and virtually every crew member on board, with some 15 barely escaping to become prisoners of the Germans. HMS Courageous and HMS Glorious would blow up in place of Queen Mary and Indefatigable, with Salamis and Hindenburg replacing Seydlitz and Derrflinger.
Just as the 4 British battlecruisers exploded, the Germans would suffer their 1st loss of the day. At 16:19, the Roon blew up, also in fireworks from gun hit induced fires. While expected, the loss of Roon threw the Germans in shock as well as the Roon's explosion felt like the Dogger Bank explosions of Seydlitz, Moltke and Blucher. Later, it was found that a Greenboy 15 inch shell from HMS Valiant or Barham hit the Roon and blew up the 5.9 inch guns, the 5.9 inch magazines and the 8 inch gun magazines based on sonar wreck discovery.
After the lost of HMS Lion due to magazine explosions, command of the squadron was hampered by the loss of Admiral Beatty and his staff. Command of Beatty's fleet passed temporarily to Hugh Evan Thomas in HMS Barham. As to make matters worse, HMS Courageous and HMS Glorious had also blown up with magazine detonations. Shortly after, HMS Southampton detected German battleships approaching the fleet. News of the German battleships and escorts were reported to the fleet. Simultaneously, the British and German destroyers fired torpedoes at attackers, but the torpedoes missed their targets except for one on the Salamis. Upon the loss of Beatty reaching him, Barry Bingham ordered the destroyers to sink more German destroyers, but lost a few to gunfire.
As soon as he himself sighted the vanguard of Scheer's distant battleship line 12 mi (10 nmi; 19 km) away, at 16:40, Evan Thomas turned his battle cruiser force 180°, heading north to draw the Germans toward Jellicoe's fleet. Due to the failure to signal the 5th Battle Squadron, the battleships were passing towards the incoming High Seas Fleet. Having received information on the presence of the High Seas Fleet by HMS Southampton, Jellicoe alerted the Admiralty in London as to the imminent fleet combat.
The next catastrophe was to occur soon.
Shortly after 17:00, the Barham, which was temporarily used as flagship for the battlecruiser squadron, also blew up, much to the surprise of the 5th Battle Squadron. The explosion, which was observed by HMS Valiant, shook the commander, but he had to command and redirect the 5th Battle Squadron after the loss of its commander onboard Barham.
At 17:13, a shell hit from the HMS Valiant hit the Hindenburg (Lutzow in reality) and pierced all the way to the ammunition magazines, blowing up the ship. It would be the second German battlecruiser to explode during the battle. Again, that was because of a Greenboy shell which pierced the secondary magazines and the heavy gun magazines.
At 17:30, HMS Malaya was hit on the starboard 6 inch guns. Other ships detected the raging fires but the ship blew up in a few minutes, leaving about 20 survivors. The blow ups came as shocks to the other battle cruisers, shocked by how two of the most modern and well armed battleships afloat in the Royal Navy could be destroyed in quick succession to the 4 British [and one German] battlecruisers. Crewmen suspected that an explosion of the 6 inch magazines or guns or penetrations through the weakly armoured deck was responsible. [Close call otl, extra shells make the hit on 6 inch guns fatal in this scenario.]
In the meantime, what was to befall the Royal and Imperial German navies would look worse.
The next tragedy to befall the battle cruisers would occur, with shells from Markgraf landing on HMS Queen Mary and detonating the turrets, sinking the ship with all hands except for 5 thrown overboard by 18:22. The Lutzow sank the HMS Invincible and HMS Indefatigable with all hands by 18 45 hours. HMAS Australia would be the only battle cruiser left in the fleet, but the commander chose to engage Lutzow and although inflicting severe damage, detonated before 19 00 hours with total loss of life. However, the Lutzow had over 20 12 inch shell hits in the hull, which would prove fatal when combined with another few more battleship shells, which was finally crippled fatally.
The Von Der Tann, having been crippled by HMS Warspite in steering, would mutually destroy each other with shells and progressive flooding. Just as 2 British armoured cruisers were blown up with all hands, HMS Valiant was shelled by German battleships and was wrecked. Due to further damage to the rudders, the ship was unable to move and after made combat incapable, was scuttled the next day. However, by the time, Greenboy shells and a torpedo had battlecruiser Salamis's bow badly damaged from 16:57 to 17:31, leaving it vulnerable to further destroyer torpedo attacks and sinking by 17:31. The Greenboy shells were later found to have more damaging impact than their predecessors.
In addition, the Markgraf and Kronprinz collided with each other after a shell damaged the former's rudders. The 2 German dreadnoughts would be finished off by the 2nd Battle Squadron's 2nd Division in exchange for sinking by progressive flooding 3 British dreadnoughts and blowing up HMS Monarch. Around 18:35, HMS Iron Duke would blow up Konig with a Greenboy shell.
The Grand Fleet then met up with the High Seas Fleet, losing Grosser Kurfurst before disengaging due to shells and a torpedo salvo from German destroyers would sink Marlborough and damage Agincourt, which would be finished off by U-66's torpedoes the next morning, while a torpedo salvo from British destroyer Onslaught would blow up the Pommern.
What had been known as the Battle of Jutland caused the loss to the British of 10 battleships, 8 battlecruisers involved, 3 armoured cruisers and 8 destroyers. In exchange, the Germans lost 4 battleships, a pre-dreadnought, 4 battle cruisers, an armoured cruiser, 4 light cruisers and 5 torpedo boats and lose WW1 by 11 November 1918 without any more fleet sortie.
The battle would be followed up by a hasty commissioning of the battleships Bayern and Baden.
Battle of Flamborough Head (Action of 29 October 1916)
On 28 October 1916, the battleships Baden and Bayern and the surviving lighter ships of 1st Scouting Group would sortie out in the Battle of Flamborough Head with the objective of completing the Battle of Jutland's objective of destroying isolated British ships.
By 3:30 p.m. the next day, the stage was set to see a 2nd dreadnought battle of 1916 at the Skagerrak when Admiral Phillimore's ships (replacing command and the previous ships of the Battlecruiser Squadron) met Admiral Hipper's ships and started firing gunshots at the enemy.
At approximately 4:00 p.m., a shell from Bayern (hastily commissioned) detonated on HMS Centurion's Y Turret. In the scenario, the fire caused by the shell left everybody dead or crippled. With nobody willing to assist the wounded men after an explosion and fire following, the fires spread and by 4:25 P.M., the Centurion had detonated with the loss of virtually every crew member on board, with some 15 barely escaping to become prisoners of the Germans. To make matters worse, HMS Emperor of India had also blown up with magazine detonations minutes earlier due to shell hits from Baden.
The next catastrophe was to occur soon. At 17:15, Baden was torpedoed and damaged by torpedoes from HMS Engadine and the newly commissioned Bayern was detached to sink the carrier with the damaged Baden. Baden would sink with progressive flooding and was unable to aid 1st Scouting Group. Bayern's shells left the carrier sinking, but Bayern was torpedoed and sunk by the Onslaught later, it took some time for Bayern to sink the carrier due to crew inexperience. All the Queen Elizabeth class ships, including HMS Queen Elizabeth, were sunken before the 29 October 1916 battle.
A torpedo salvo from German destroyers would sink Thunderer and damage Royal Oak, which would be finished off by U-66's torpedoes the next morning, while a torpedo salvo from British destroyer Onslaught would sink the Bayern.
In addition, 2 armoured cruisers (Achilles and Cochrane) were sunk with the loss of all hands, while the disabled Donegal would sink the next day (raider Leopard would be sunk by another cruiser). The battle would result in unrestricted submarine warfare and complete Germany's WW1 defeat by 11 November 1918. What had been known as the Battle of Flamborough Head caused the loss of 4 British battleships, 3 armoured cruisers, a seaplane carrier and 10 destroyers. In exchange, the Germans lost 2 battleships, 2 light cruisers and 5 torpedo boats.
Maximum ship explosions at Jutland to consist of 8 British battlecruisers, 3 British dreadnoughts, 1 German battlecruiser, 1 German armoured cruiser, 1 German dreadnought and 1 German pre-dreadnought.