Two days later, heading for occupied France for repairs, Bismarck was attacked by fifteen Fairey Swordfish torpedo bombers from the aircraft carrier HMS Ark Royal; one scored a hit that rendered the battleship's steering gear inoperable.

The ships secretly exceeded the figure by a wide margin, though before either vessel was completed, the international treaty system had fallen apart following Japan's withdrawal in 1937, allowing signatories to invoke an "escalator clause" that permitted displacements as high as 45,000 long tons (46,000 t).

The information provided the Royal Navy with its first full description of the vessel, although it lacked important facts, including top speed, radius of action, and displacement.

Bismarck and Tirpitz were to sortie from the Baltic and rendezvous with the two Scharnhorst-class ships in the Atlantic; the operation was initially scheduled for around 25 April 1941, when a new moon period would make conditions more favourable.

[31] At a final meeting with Raeder in Paris on 26 April, Lütjens was encouraged by his commander-in-chief to proceed and he eventually decided that an operation should begin as soon as possible to prevent the enemy gaining any respite.

[42] Gotland transmitted a report to naval headquarters, stating: "Two large ships, three destroyers, five escort vessels, and 10–12 aircraft passed Marstrand, course 205°/20'.

[43] The code-breakers at Bletchley Park confirmed that an Atlantic raid was imminent, as they had decrypted reports that Bismarck and Prinz Eugen had taken on prize crews and requested additional navigational charts from headquarters.

The following morning, radio-intercept officers on board Prinz Eugen picked up a signal ordering British reconnaissance aircraft to search for two battleships and three destroyers northbound off the Norwegian coast.

Shortly after 12:00, the flotilla reached Bergen and anchored at Grimstadfjord, where the ships' crews painted over the Baltic camouflage with the standard "outboard grey" worn by German warships operating in the Atlantic.

[57] Lütjens gave permission for Prinz Eugen to engage Suffolk, but the captain of the German cruiser could not clearly make out his target and so held fire.

At 05:07, hydrophone operators aboard Prinz Eugen detected a pair of unidentified vessels approaching the German formation at a range of 20 nmi (37 km; 23 mi), reporting "Noise of two fast-moving turbine ships at 280° relative bearing!

[68] Lütjens then ordered Prinz Eugen to drop behind Bismarck, so she could continue to monitor the location of Norfolk and Suffolk, which were still 10 to 12 nmi (19 to 22 km; 12 to 14 mi) to the east.

The Admiralty ordered the light cruisers Manchester, Birmingham, and Arethusa to patrol the Denmark Strait in case Lütjens attempted to retrace his route.

[92] By around 17:00, the crew aboard Prince of Wales restored nine of her ten main guns to working order, which permitted Wake-Walker to place her in the front of his formation to attack Bismarck if the opportunity arose.

[96] At 22:00, Victorious launched the strike, which comprised nine Fairey Swordfish torpedo bombers of 825 Naval Air Squadron, led by Lt Cdr Eugene Esmonde.

The inexperienced aviators nearly attacked Norfolk and the U.S. Coast Guard cutter USCGC Modoc on their approach; the confusion alerted Bismarck's anti-aircraft gunners.

Bismarck evaded seven of the torpedoes launched at her, but the eighth[99][100][97] struck amidships on the main armoured belt, throwing one man into a bulkhead and killing him and injuring five others.

The ship suffered more serious damage from manoeuvres to evade the torpedoes: rapid shifts in speed and course loosened collision mats, which increased the flooding from the forward shell hole and eventually forced abandonment of the port number 2 boiler room.

[83] At 10:30 on 26 May, a Catalina piloted by British Flying Officer Dennis Briggs and co-piloted by Ensign Leonard B. Smith of the US Navy located her, some 690 nmi (1,280 km; 790 mi) northwest of Brest.

Throughout the night and into the morning, Vian's destroyers harried Bismarck, illuminating her with star shells and firing sixteen torpedoes in nine separate attacks, none of which hit.

[136] Between 05:00 and 06:00, Bismarck's crew attempted to launch one of the Arado 196 float planes to carry away the ship's war diary, footage of the engagement with Hood, and other important documents.

[141] Thereafter, Bismarck's ability to aim her guns deteriorated as the ship, unable to steer, moved erratically in the heavy seas and deprived Schneider of a predictable course for range calculations.

[149][150] With the bridge personnel no longer responding, the executive officer Fregattenkapitän Hans Oels took command of the ship from his station at the Damage Control Central.

At around 10:05 to 10:10, a 14-inch shell from King George V penetrated the upper citadel belt and exploded in the ship's aft canteen, killing Oels on the gun deck and about a hundred others.

Ballard kept the wreck's exact location a secret to prevent other divers from taking artefacts from the ship, a practice he considered a form of grave robbing.

[179] Naval historians William Garzke and Robert Dulin noted that the British battleships were shooting at very close range; the flat trajectory of the shells made it difficult to hit the relatively narrow target represented by the belt armour above the waterline due to the high waves, caused by gale force winds, which shielded the belt armour as shells that fell short would either strike the water and ricochet up into the superstructure or explode after striking the waves.

[185] The 2002 documentary Expedition: Bismarck, directed by James Cameron and filmed in May–June 2002 using smaller and more agile Mir submersibles, reconstructed the events leading to the sinking.

[187] Although around 719 large calibre shells were fired at Bismarck that morning, Cameron's survey noted only two instances where the 320 mm main side belt armour had actually been fully penetrated in the visible parts of the hull.

[189] The later close-range shelling (including by secondary armament) "devastated the superstructure and exposed parts of the hull above the waterline, and caused massive casualties", but contributed little to the sinking of the ship.

Ballard estimated that Bismarck could still have floated for at least a day when the British vessels ceased fire and could have been captured by the Royal Navy, a position supported by Ludovic Kennedy (who was serving on the destroyer HMS Tartar at the time).