HMS Hood (51) - Modern Theories On The Sinking

Modern Theories On The Sinking

The exact cause of the loss of Hood remains a subject of debate. The principal theories include the following causes:

• A direct hit from a shell penetrated to a magazine aft. Such a shell could only have come from the Bismarck, since the Prinz Eugen was no longer firing at the Hood at the time of the explosion. As noted above, this version of events was almost taken for granted at the time of the sinking. Doubt first arose as a result of eyewitness testimony that the explosion that destroyed Hood originated near the mainmast, well forward of the aft magazines (for example, the sketch shown prepared for the second board of enquiry by Captain Leach of Prince of Wales). At the second board, expert witnesses suggested that what was observed was the venting, through the engine-room ventilators, of a violent—but not instantaneous—explosion or deflagration in the 4-inch magazines. The same deflagration would have collapsed the bulkhead separating the 4-inch and 15-inch magazines, resulting very quickly in a catastrophic explosion similar to those previously witnessed at Jutland. This theory was ultimately adopted by the board.
• A shell, falling short and travelling underwater, struck below the armoured belt and penetrated to a magazine. During the same action, Prince of Wales received a hit of this type from a 15-inch shell, which travelled underwater for about 80 feet (25 m), struck about 28 feet (8 m) below the waterline, penetrated several light bulkheads and fetched up, without exploding, against the torpedo bulkhead. The second board considered this theory improbable, arguing that the fuse, had it worked at all, would have detonated the shell before it reached the ship. According to Jurens's calculations, one of Bismarck's shells that fell approximately 20 feet (6.1 m) short of Hood could have penetrated the side of the ship beneath the armour belt and would have detonated in the vicinity of the ship's magazines if the fuse worked.
• The ship was destroyed by the explosion of her own torpedoes. According to Goodall's theory, the ship's torpedoes could have been detonated either by the fire raging on the boat deck or, more probably, by a direct hit from Bismarck. This would have blown out the side of the ship, destroying the girder strength of the hull; the force of water entering the hole, at a speed of nearly 30 knots (56 km/h), would then shear the stern section from the rest of the hull.
• The fire on the boat deck penetrated to a magazine. Evidence given to the second board indicated that the doors for the 4-inch ammunition supply trunks were closed throughout the action. It remains possible that a door or trunk could have been opened up by an enemy shell, admitting flames to the magazine. Alternative routes for admission of flame could have been the ventilation or venting arrangements of the magazines or, as Ted Briggs suggested, through the floor of a 15-inch gunhouse.
• The explosion was initiated by 4-inch ammunition stored outside the magazines. Writing in 1979, the naval historian Antony Preston claimed that the aft magazines of Hood were "surrounded by additional 4-inch (102 mm) anti-aircraft shells outside the armoured barbettes. Such unprotected stowage could have been detonated either by the boat-deck fire or by a shell from Bismarck."
• The ship was blown up by her own guns. At the second board, eyewitnesses reported unusual types of discharge from the 15-inch guns of Hood, suggesting that a shell could have detonated within the gun, causing an explosion within the gunhouse. It is possible that, under the stress of combat, the safety measures, introduced after the disasters at Jutland to prevent such an explosion reaching the magazines, could have failed.

An extensive review of these theories (excepting that of Preston) is given in Jurens's 1987 article. Its main conclusion is that the loss was almost certainly precipitated by the explosion of a 4-inch magazine, but that there are a number of ways in which this could have been initiated, although he rules out the boat deck fire or the detonation of her torpedoes as probable causes. In Jurens's opinion, the popular image of plunging shells penetrating Hood's deck armour is inaccurate, as by his estimation the angle of fall of Bismarck's 15-inch shells at the moment of the loss would not have exceeded about 14°, an angle so unfavourable to penetration of horizontal armour that it is actually off the scale of contemporaneous German penetration charts. Moreover, computer-generated profiles of Hood show that a shell falling at this angle could not have reached an aft magazine without first passing through some part of the belt armour. On the other hand, the 12-inch belt could have been penetrated, if Hood had progressed sufficiently far into her final turn.

A more recent development is the discovery of Hood's wreck. Inspection of the wreck has confirmed that the aft magazines did indeed explode. The stern of the Hood was located, with the rudder still in place, and it was found that this was set to port at the time of the explosion. Furthermore, a section of the bow immediately forward of 'A' turret is missing, which has led historian and former Dartmouth lecturer Eric J. Grove and expedition leader David Mearns to believe that "either just before or just after leaving the surface, the bow suffered massive internal damage from an internal explosion", possibly a partial detonation of the forward 15-inch magazines. It has been suggested that the fatal fire spread from the aft end of the ship through the starboard fuel tanks, since the starboard side of Hood "appears to be missing most, if not all of its torpedo bulge plating".

The evidence of the wreck refutes Goodall's theory, while the eyewitness evidence of venting from the 4-inch magazine prior to the main explosion conflicts with the theory that the Hood was blown up by her own guns. The other theories listed above remain valid possibilities.