Why Bismarck Survived 400 Shell Hits But Hood Sank From One

On the morning of May 24, 1941, HMS Hood opened fire on the German battleship Bismar at a range of approximately 26,500 yd.

8 minutes later, Hood was gone, broken in half, sinking by the stern, 1,415 men dead, three survivors.

3 days after that, Bismar was surrounded by British battleships, cruisers, and destroyers.

She absorbed around 400 shell hits and multiple torpedo strikes over 90 minutes of continuous bombardment.

Her guns were silenced.

Her superructure was wrecked, but her armored citadel held.

She was scuttled by her own crew or sank from flooding.

More than 2,100 of her crew died.

116 survived.

Two ships, two philosophies, one built for speed, the other built for protection.

This is not about which ship won the battle.

Bismar sank Hood, but Bismar was destroyed 3 days later.

This is about what their designs reveal, about the choices the Royal Navy and the Creeks Marine made, why they made them, and what happened when those choices were tested in combat.

The specifications tell the first part of the story.

Hood displaced 42,670 tons standard, 860 ft long, over 2 and 1/2 football fields.

Her beam was 104 ft.

She carried eight 15-in guns in four twin turrets, identical in caliber to Bismar’s main armament.

Her design speed was 32 knots, making her one of the fastest capital ships afloat when she was commissioned in 1920.

She was also the largest warship in the world for 20 years.

Bismar displaced 41,700 tons standard, but 50,300 tons at full load, nearly 8,000 tons heavier than hood when fully equipped.

She was shorter at 823 ft, but significantly wider with a beam of 118 ft.

That extra 14 ft of beam gave her a more stable gun platform and room for a deeper underwater protection system.

She carried eight 15-in guns in four twin turrets.

Her speed was 30.8 knots on trials, roughly a knot and a half slower than Hood.

On paper, these ships look comparable.

Same main armament, similar displacement, similar speed, but the numbers hide the critical difference.

Protection.

Hood’s armor was designed in 1916 during the First World War and modified after the Battle of Jutland.

Her main belt was 12 in of crook cemented armor, angled outward at 12° from the vertical.

That angling was innovative for its time, giving the belt an effective thickness closer to 14 or 15 in against flat trajectory shells.

Between the main barbetts, this belt extended 562 ft along the water line.

Above it sat a 7-in middle belt and a 5-in upper belt against shells coming in on a flat trajectory at close to medium range.

Hood’s belt was formidable, comparable to contemporary British battleships.

The problem was not her sides.

The problem was her roof.

Hood’s horizontal protection was distributed across multiple thin decks rather than concentrated in a single thick layer.

The four castle deck was roughly 2 in thick.

The upper deck was 2 in over the magazines.

The main deck was 3 in over the magazines and just 1 in elsewhere.

Below that, the lower deck added another 2 in over the magazines.

The theory was that each successive layer would slow an incoming shell, trigger its fuse prematurely, and absorb the fragments before they reached the vitals.

In 1916, when naval gunnery was inaccurate at long range, and shells fell at shallow angles, this made sense.

By 1941, it was obsolete.

Modern fire control had made longrange gunnery far more accurate.

At ranges beyond 20,000 yd, shells arrive at steep angles, plunging down onto the deck rather than striking the belt.

Hood’s thin, distributed deck armor could not stop a 15-in shell falling at high angles.

The Admiral T knew this.

A major refit was planned for 1941 that would have doubled her deck protection to 6 in, reinforced her magazine crowns, and modernized her anti-aircraft armament.

But the war made it impossible to take Hood out of service.

She was too valuable.

She sailed into the Denmark Strait with the armor she had been given 21 years earlier.

Bismar’s protection was designed in 1936, incorporating every lesson from Jutland and two decades of armor development.

Her main belt was 320 mm of crook cemented armor, roughly 12.6 in set vertically.

It extended 170 m along the water line, covering 70% of her length, the greatest proportional extent of any modern battleship.

But Bismar’s real advantage was in her horizontal and underwater protection.

Her armor was arranged in a layered system unlike any other contemporary battleship.

The upper deck was 50 mm of homogeneous armor designed to trigger the fuses of incoming shells and strip away their armor-piercing caps.

Below that, one deck down, sat the main armored deck, 80 mm thick over machinery and 95 mm over the magazines.

The outer edges of this main deck sloped downward at 22° to meet the bottom of the main belt, and at these slopes, the armor thickened to 110 mm.

This turtle back arrangement meant that any shell penetrating the belt would then have to defeat the sloped deck armor before reaching the vitals.

In total, Bismar’s effective horizontal protection over the magazines was roughly equivalent to 5 in of solid armor.

Nearly double hoods 3 in on the main deck, and Bismar’s system was designed as an integrated hole with each layer working together, while hoods was a collection of thin plates added incrementally as designers tried to patch a fundamentally pre-jutland concept.

Bismar also had exceptional underwater protection and compartmentalization.

22 watertight compartments, a torpedo bulkhead of 45 mm running the length of the citadel, redundant electrical and pumping systems.

The ship was designed from the keel up to absorb punishment and keep fighting.

Her armor alone accounted for roughly 40% of her combat displacement, the highest proportion of any battleship except the Japanese Yamato class.

These differences were not accidental.

They reflected fundamentally different naval doctrines.

Hood was a battle cruiser.

Her design descended from Admiral Jackie Fischer’s revolutionary concept of 1908.

Fischer believed that speed was protection.

A fast capital ship with heavy guns could chase down enemy cruisers and destroy them with superior firepower, then use her speed to escape enemy battleships she could not outfight.

Armor was sacrificed to achieve that speed.

The thinking was simple.

If you can choose the range and the moment of engagement, you do not need as much armor.

The Battle of Jutland in 1916 brutally exposed this logic.

Three British battle cruisers, inddehaticable, Queen Mary and invincible, blew up and sank with catastrophic loss of life.

Flash from shell hits had traveled down into their magazines, igniting the cordite propellant.

Hood’s design was already under construction when Jutland was fought and roughly 5,000 tons of additional armor were added in response.

Her belt was thickened, flashtight measures were improved.

Magazine crowns were reinforced, but the fundamental compromise remained.

Hood was still a battle cruiser.

She was still optimized for speed over protection.

Her deck armor was still inadequate against plunging fire.

And as fire control technology improved throughout the 1920s and 30s, the ranges at which accurate hits could be scored grew steadily longer, which meant shells fell at steeper and steeper angles.

The threat that Hood’s designers had considered unlikely in 1916, had become routine by 1939.

Bismar represented a completely different philosophy.

Germany’s post Versailles Navy, rebuilt under the 1935 Anglo-German Naval Agreement, was designed for a specific strategic mission.

Germany could never match the Royal Navy in numbers.

Instead, German capital ships were built to operate as surface raiders in the Atlantic, attacking merchant convoys while evading the vastly larger British fleet.

This meant they had to be able to sustain damage from encounters they could not avoid, fight their way clear, and continue operating far from home ports.

Every aspect of Bismar’s design reflected this requirement.

Balanced protection meant she could take hits from any direction at any range.

Extensive compartmentalization meant a single torpedo or shell hit would not her.

Redundant systems meant she could absorb damage to critical equipment and keep fighting.

Speed of 30 knots meant she could outrun most British battleships.

Though not battle cruisers, she gave up two knots compared to Hood, but gained enormously in survivability.

The Denmark Strait proved both philosophies right and wrong at the same time.

Vice Admiral Lancelot Holland, flying his flag in Hood, knew exactly how vulnerable his ship was.

He was a gunnery expert.

He understood that at ranges beyond 20,000 yd, Bismar’s shells would fall at angles steep enough to penetrate Hood’s deck armor.

His plan was to close the range as rapidly as possible, reducing the time Hood spent in the danger zone.

At closer ranges, shells would arrive on flatter trajectories and strike Hood’s 12-in belt instead of her 3-in deck.

Holland’s original plan was to intercept Bismar from ahead, approaching rapidly from the west in the early morning darkness, where Hood and Prince of Wales would be hidden against the Merc while Bismar was silhouetted against the afterglow.

This would have allowed a swift close-range engagement that played to Hood’s strengths, her belt armor, and her firepower.

It did not work out that way.

Overnight contact was lost when the cruiser suffered temporarily lost radar tracking.

Holland altered course to compensate, guessing at Bismar’s movements.

When contact was regained and the Germans were finally cighted at 5:35 on the morning of May 24, Holland’s force was on an unfavorable bearing.

Instead of cutting across Bismar’s bow, he was converging at an angle that closed the range slowly, exposing Hood to plunging fire for far longer than he had intended.

Worse, the angle of approach meant Hood’s after turrets could not bear.

She went into battle with only half her main armament firing.

Hood opened fire at 552 at approximately 26,500 yd.

Holland initially ordered both ships to engage the leading German vessel, believing it was Bismar.

It was actually Prince Jugan.

Prince of Wales correctly identified Bismar and engaged her independently.

Hood may have continued firing at Prince Jugan for her first salvos before correcting.

Bismar opened fire at 555 at roughly 22,000 yd.

Both German ships concentrated on Hood.

Prince Yogen’s 8-in high explosive shells hit Hood amid ships almost immediately, starting a fierce fire among the ready use ammunition for the 4-in anti-aircraft guns and the unrotated projectile launchers on the boat deck.

At approximately 600 hours, Holland ordered a 20° turn to port to open the arcs for his after turrets.

At that moment, Bismar’s fifth salvo arrived.

The range had closed to less than 18,000 yd.

At least one 15-in shell struck Hood near her after magazines.

The exact path of penetration remains debated.

The official board of inquiry concluded that the probable cause was direct penetration of the protection by one or more 15-in shells at a range of roughly 16,500 yd, resulting in the explosion of one or more of the aft magazines.

More recent analysis suggests the shell may have entered just above the belt and below the deck, traveling through the weaker side protection into the magazine spaces rather than plunging through the deck from above.

Regardless of the exact path, the result was the same.

The shell reached Hoods after magazines.

112 tons of cordite propellant detonated.

A column of flame shot hundreds of feet into the air.

Hood’s stern sank almost immediately while her bow rose clear of the water.

Within three minutes, one of the most famous warships in history had disappeared beneath the Denmark Strait.

Of her crew of 1,418, three men survived.

Midshipman William Dundus, able seaman Robert Tilburn, signalman Ted Briggs.

3 days later, Bismar’s own design was put to its ultimate test.

After the Denmark Strait, Prince of Wales had hit Bismar with three 14-in shells.

One struck her bow, flooding forward compartments and contaminating fuel tanks.

This single hit forced Bismar to abandon her Atlantic raiding mission and turned toward occupied France for repairs.

On the evening of May 26th, Swordfish torpedo bombers from the carrier Ark Royal scored two hits.

One struck her midship and caused little damage.

The other hit Bismar’s stern, jamming her rudders.

She could no longer steer.

On the morning of May 27, the battleships King George V and Rodney, supported by the heavy cruisers Norfolk and Dorsucher, closed in.

The four British warships fired approximately 2800 shells during the engagement.

Around 400 struck Bismar.

Rodney fired 3806in shells alone.

King George V fired 339 14-in rounds.

Bismar’s guns were silenced within the first 30 minutes.

Her turrets were blown apart one by one.

Her superructure was reduced to burning wreckage, but her armored citadel held.

Neither the main belt nor the armor deck were conclusively penetrated during the engagement.

The German armor scheme did exactly what it was designed to do.

It kept the shell out of the vitals.

Bismar finally sank at 10:40, roughly 90 minutes after the bombardment began.

Whether she sank from accumulated flooding, torpedo damage, or deliberate scuttling by her crew remains debated.

Examination of the wreck on the ocean floor found that the hull had not imploded, indicating she was flooded before she reached crushed depth.

The most likely conclusion is that a combination of torpedo damage, progressive flooding through blast weekend seams, and deliberate scuttling by the crew all contributed to her loss.

The verdict.

This comparison is not about declaring a winner.

Hood was not designed to fight Bismar.

She was designed in 1916 to fight First World War dreadnots at ranges where her belt armor would be effective and her speed would give her the initiative.

For two decades, she did exactly that.

She was the most recognized warship in the world, the embodiment of British naval power during the interwar years.

And she served effectively in multiple roles from showing the flag around the empire to hunting surface raiders in the Atlantic.

Bismar was not designed to fight Hood.

She was designed in 1936 to raid Atlantic convoys, survive encounters with British warships, and returned to port.

Her armor scheme was brilliantly engineered for sustained punishment.

Her compartmentalization was exceptional.

Her damage control systems were redundant.

In her final battle, she demonstrated exactly the survivability her designers intended, absorbing a weight of fire that would have sunk any other capital ship in the world in a fraction of the time.

Where Hood excelled was speed.

32 knots gave her the ability to intercept threats that slower battleships could not catch.

Her 15-in guns were equal to Bismar’s in caliber and superior in shell weight.

And in 1920, her belt armor was among the best in the world.

Where Hood failed was in her deck protection.

3 in of armor over the magazines was inadequate for 1940s warfare.

Her distributed multi-deck system could not defeat modern armor-piercing shells at long range.

And the planned refit that would have corrected this never happened because the war came too soon.

Where Bismar excelled was in protection.

Her layered armor scheme, her turtle back deck slopes, her compartmentalization, and her damage control redundancy made her extraordinarily difficult to sink.

40% of her displacement was armor, the highest proportion of any European battleship.

Where Bismar failed was strategically.

She was a single ship operating against the entire Royal Navy.

One lucky hit from Prince of Wales contaminated her fuel and forced her to break off the mission.

One torpedo from a biplane jammed her rudder and sealed her fate.

No amount of armor can protect a lone raider from an entire navy determined to hunt it down.

The Denmark Strait teaches one clear lesson about design philosophy.

Speed cannot replace armor.

Fisher’s battle cruiser concept that a fast ship with heavy guns could avoid the situations where thin armor mattered assumed a commander would always have the luxury of choosing the range and the moment.

Holland did not have that luxury.

Overnight confusion, lost radar contact, and an unfavorable approach angle forced Hood into exactly the engagement her designers had never intended.

A longrange gunnery jewel against a modern battleship with superior deck protection.

But it also teaches a second lesson.

Even superior protection has limits.

Bismar’s armor kept her citadel intact under the heaviest naval bombardment of the war.

It did not save her.

A jammed rudder, progressive flooding, and the relentless concentration of an entire navy rendered her armor academic.

Design matters, but so does strategy.

And no ship, however well protected, can survive alone against overwhelming force.

Hood was the right ship for 1920.

Bismar was the right ship for 1941.

The tragedy of the Denmark Strait is that Hood was still fighting in 1941 with 1916 protection against a threat her designers could never have imagined.

She deserved the refit she never received.

The 1415 men who died with her deserved better than to be sent into battle with armor that belonged to a previous