The Wreck of DKM Bismarck − A Marine Forensics Analysis 1 The ...

The Wreck of DKM Bismarck − A Marine Forensics Analysis
SOME OBSERVATIONS
Bismarck's sinking was a brutal, up-close action. Admiral Tovey wanted to sink Bismarck
with the gunfire at his disposal. Swordfish aircraft with torpedoes were in the vicinity but were
not called upon to enter the action. Point-blank fire was relatively ineffective, with many shells
skipping off the water and riddling the superstructure pointlessly, or missing entirely because of
the low freeboard. At short ranges, the salvo dispersion pattern was narrower and more
elongated. Since both British battleships were firing almost straight abeam Bismarck, on either
side, they were trying to hit a target with very little freeboard in a high sea state. These miserable
conditions − violent seas and marginal visibility − made good gunnery accuracy an “iffy”
prospect, at best.
Unless the shells hit below the armor belt, very unlikely at such close ranges because of
protective effect of water with such flat trajectories, they were not going to cause damage that
would sink the ship.
As a result of the port list, by the end of the gunnery engagement, the lower edge of the
armor belt on the port side may have been submerged some 7-8 meters below the water (perhaps
two deck heights) − much more than normal. In a sense, the port list contributed to protecting the
port side of the damaged ship from gunfire, every degree of added list decreasing the
vulnerability of many vital compartments.
By 0945; it was becoming obvious that British shellfire was not contributing to sinking
the ship. The two battleships and two heavy cruisers had fired away for the last hour without any
apparent effect. Shellfire had riddled the stack structure, swept away searchlights, demolished
the antiaircraft batteries, pummeled the superstructure, carried away hose reels and fire
extinguishers, and destroyed the teak deck in areas. Crew members who were in exposed areas
were killed or severely wounded. Close-range gunnery later in the engagement devastated
Bismarck’s superstructure and the parts of the hull structure above the waterline, overwhelming
and defeating the ship and causing massive casualties, but not speeding the sinking of the ship.
Bismarck was overwhelmed and defeated by the gunfire and torpedoes of the Royal
Navy, gradually sinking due to uncontrollable progressive flooding. Scuttling charges were
detonated shortly after 1020, and the battered ship listed heavily to port around 1035. Shortly
thereafter, the ship capsized to port and sank by the stern, her bow disappearing around 1040.
THE WRECK
The hulk of Bismarck is lying upright, with its bow facing West across the slope of an
extinct volcano on a heading between 250-290°. The bow-first impact caused an enormous
disturbance to the terrain, including an impact crater where the bow first hit, and an impact
trough where the hull slammed down moments later, both of which are surrounded by ejecta.
The hull immediately slid South down the seamount stern first, gouging a deep slide scar which
widened as the hull turned broadside to the slope and continued to slide at a slight bow-first
angle. In this broadside area the slide scar is shallower and more chaotic. Down slope, beyond
the wreck, there is a huge alluvial fan of sediment and debris. The wreck caused a terrestrial
avalanche on the seabed which was exacerbated by a powerful turbidity flow.
During her plunge through the water column, Bismarck planed north, transiting about 500
meters horizontally to the North from her sinking position on the surface. She struck the side of a
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