HIJMS Kirishima, 2019

Interesting footnote to the Second Naval Battle of Guadalcanal; a second underwater archeological investigation of the wreck of the battlecruiser Kirishima, sunk in the action I wrote up back in November 0f 2012. The wreck was discovered in 1992, but the return allowed for substantially better observation of the ship.

If you recall, this was one of the handful of surface gun actions in WW2, in which the new battleship USS Washington hammered the old battlecruiser:

"USS Washington slid through the night, a great gray steel ghost. She had tracked a large radar target but held her fire, unsure of whether the object was friendly or enemy. Finally she was within 9,000 yards, and Kirishima lit off her searchlights and fired on South Dakota. Washington's gunners immediately opened up and pasted the living shit out of the old battlecruiser; at least nine 16" shells and probably something like 40 6" projos impacted within minutes. Kirishima lit up like a balefire. Her rudder was jammed hard over to port, hundreds of her crew were dead, many more maimed or injured. Within minutes the elderly battlecruiser was transformed from a fighting ship into a wreck."

Based on the new investigation it sounds like Washington's shooting was better than we'd thought:

"I believe that it is safe to say that Kirishima was struck between 17 and 21 times by 16-inch projectiles and between 17 and 20 times by 5-inch projectiles." (Lundgren, 2019)

One of the intriguing sidenotes I found in this article was the observation that one of the major contributing factors to the destruction of the Japanese battlecruiser was it's projectile load.

The primary mission of the IJN task force that November night was to bombard and destroy Henderson Field, therefore Kirishima carried a large number of the "Type 3" bombardment projectiles. These were thinner walled than the typical armor-piercing 14" projo but, more critically, were filled with a different explosive.

Both her forward ("A" and "B") turrets were hit hard, and both barbettes - the armored column chambers where projectiles and propellants are stored - were penetrated. Here the USN projectiles would have exploded, and very likely caused sympathetic detonation of the IJN projos.

"Within Turret "A" barbette - assuming the Japanese had pre-positioned ten Type 3 projectiles per gun in advance of the battle - the barbette structure would hold twenty projectiles prior to the battle. Turret‘"A" fired three times during the battle, expending six shells and thus leaving at minimum fourteen projectiles within the barbette and hoists when it was destroyed. Using the figures above, each projectile contained over 44 lbs (20 kg) of incendiary material of which 18lbs. (8.2 kg) was magnesium. With an estimated fourteen projectiles within barbette one ("A" turret barbette) this single compartment had 252.3lbs (114.4kg) of magnesium powder available to burn within barbette." (Lundgren, 2019)

Magnesium is a whole different cat than the usual nitrocellulose explosive. It burns hot, really hot, like 3,000-degrees hot, and can't be extinguished without CO2 firefighting chemical foam.

So the implication is that 1) Washington's 16-inch guns hit and penetrated both Kirishima's forward turrets, and 2) along with wrecking the turrets and killing the guncrews, the USN hits 3) ignited the Type 3 bombardment ammunition, producing the immense flames - burning magnesium can flare as much as 15-20 feet high - that were reported by both Japanese and American sailors. Those fires would have quickly made the battlecruiser unfightable as at the same time more large-caliber hits below the waterline were sinking her.

Worth reading the whole thing.