(The fourth of a four-part series)
© 2007 Jeffrey R. Cox
The final fate of the Fuso has always been more of an assumption that anything else. She took a torpedo, it started a fire, the fire detonated her magazines, which blew the ship in half. Not much to tell, so the story goes, anyway.
Tully is the first historian I have seen anywhere to take a closer look at the Fuso. The disaster that befell her does seem to have been neglected. Many a ship suffered a magazine explosion, many a ship was blown in two, several suffered from both. Why is Fuso unique?
Willmott points out that the fact that Fuso was hit by one torpedo and blown in half with both halves set completely afire is “somewhat surprising and apparently without parallel in the Second World War.” It may have been two hits, as the Melvin would argue, but the real fascination here is that both halves remained afloat. Tully lists several instances where ships were blown into two sections and remained afloat for a period to time, but his list notwithstanding, Fuso seems to stand out both for the fire and the hint that one or both halves could have continued floating but for intervention by US forces. There is even a suggestion that the stern half may have retained propulsive power and the surviving crew may have tried to beach her.
Oldendorf's pursuit down the Surigao Strait the morning of October 25, 1944. The ships in the foreground (light cruiser Denver) and right center (destroyer) are US. Notations are written on the original photo. Notation at right center reads, "Enemy DD under fire." It points to the Japanese destroyer Asagumo, barely visible at right center just left of the US destroyer. Notation at far right reads, "Burning enemy ships." Beneath that notation at far right can be seen three plumes of smoke from burning Japanese ships. Those plumes would be from the heavy aircraft cruiser Mogami and the two halves of the battleship Fuso. The Mogami is probably the source of the plume on the far right.
The question of the fate of the Fuso was examined by the Navy’s Bureau of Ships. The War College Analysis contains this note from Rear Admiral Albert G. Mumma:
It is our conclusion that it is well nigh impossible for the Fuso to have broken into two nearly equal parts because of her very rugged and damage resistant structure. The USS Arizona did not show any evidence of hull failure in the area enclosed by the armor belt, even though a massive magazine explosion had occurred.Leaving aside for the moment the fact that Mumma actually used the term “well nigh” in a sentence in 20th century America, his stated conclusion seems to be more assumption than anything else, an assumption that does not withstand scrutiny well. Let’s return to the evidence. Without the wreck of the Fuso or her log available, the only evidence we have is eyewitness testimony – the most unreliable evidence, as any investigator or trial lawyer will attest, but it is all we have.
It is however considered possible that the Fuso may have lost her bow as a result of torpedo damage. Although our war experience does not include this type of failure in battleships, several cases exist where cruisers suffered this type of damage. In the case of the USS Helena (CL-50) the bow section remained afloat for more than twelve hours.
It is probable therefore that if other evidence indicates the presence of two floating bodies this can best be explained by the separation of the bow from the main hull of the battleship.
1. Fuso is hit at 3:09 am.
The Mogami observed, “Direct torpedo hit on starboard side of Fuso amidships […]”
The Melvin reports “0309: Approximate time that our torpedoes crossed enemy track, two large and separate explosions seen.”
Piecing together the reports from the Mogami and the Melvin, at 3:09 am the Fuso was hit by one or two torpedoes from the Melvin. The hits were on the starboard side, probably amidships.
2. Fuso begins to list and lose speed.
Again, Mogami said the torpedo hit(s) “caus[ed] [the Fuso] to list to starboard and lose speed.”
3. No communications received from Fuso.
The record indicates no communications were received from the Fuso after she was hit at 3:09.
4. Fuso sheers out of formation.
Again from Mogami, after the torpedo hit(s), “Fuso fell back, and Mogami moved on behind Yamashiro.” The US warships tracked her sheering out to starboard. After she was torpedoed, the Fuso sheered to starboard to clear the formation and prevent the Mogami behind her from running into her stern.
5. Fuso turns around at 3:32 am.
Slowed down by the torpedo damage, the Fuso initially continued going northward, toward the US battle line, but at 3:23 the US PT boats tracked her turning around and heading back southward.
6. Shigure sights the Fuso at around 3:30 am.
Shigure had turned around at 3:25 to look for the Yamashiro, believing she was the battleship that had dropped out. Nishino later reported, “While searching […] the lookout informed me he had sighted what he thought was the Yamashiro sinking.” If they indeed saw a battleship, this would have been the Fuso, not the Yamashiro. Shigure turned around to resume her northward course at 3:30,
6. A series of detonations begins at 3:38 am, culminating in the massive 3:45 am explosion of the Fuso.
At 3:38 am the Hutchins reported three detonations – “two faint and a loud snap” – from the Fuso. The PTs shadowing the Fuso reported that she suddenly “burst into flames about [3:45 am].” The explosion was witnessed as far away as the US battle line, where the battleship Mississippi saw the ship enveloped in flames from the waterline to the mastheads.
7. At 3:50 am, the Fuso breaks into two sections.
At 3:50, the US radar tracked the pip from the Fuso splitting into two.
8. The two sections of the Fuso separate.
According to Tully, American radar tracks show the stern section of the Fuso swinging to port, to the southeast, on a diverging line from the other half. By 4:00 am this section had opened the range between the pieces to 2,000 yards – more than a mile – after which its position remained fairly constant relative to the bow.
9. The PT boats’ descriptions of the Fuso after 3:50 am
The PT boats tracking the remnants of the Fuso described her two sections as “burning furiously.”
10. The Second Striking Force’s description of the Fuso at around 4:05 am.
According to Mori, Shima’s force sighted the remnants of the Fuso at around 3:30 am. This is obviously not correct, as the Fuso had not yet exploded. Judging by their having sighted “three fires” – the Mogami and the two halves of the Fuso – and the collision with the Mogami taking place at 4:30 am, they probably sighted the Fuso somewhere around 4:00 am. The War College puts it at 4:05.
Shima himself said the Fuso’s fires were burning “like steel-mill flames.” Mori said he “saw two fires, two ships burning, very big ships.” He went on to say:
When we first saw that fire, I judged it was about 20,000 meters from their position. Although we knew they were Japanese vessels on fire we did not bother with them, just progressed. […] We thought it was two battleships, but when we arrived at Manila we heard that it was one battleship (Yamashiro) and three destroyers close together instead of two battleships.11. Louisville’s description of the Fuso at 5:31 am.
At 5:31, the Louisville opened fire on “what seems to have been the bow” of the Fuso. Louisville described Fuso as large but “no course, speed zero. Very large fire burning.”
12. The Kanihaan PT’s description of the Fuso at 6:52 am.
At 6:52 am, PT’s 495, 489 and 492 closed to within 700 yards of the Fuso’s position and found the fire still burning, but no ship left.
These puzzle pieces, unfortunately, only outline the picture, but leave very large gaps and consequently do not solve it. Only the broad outlines can be agreed upon:
1. Fuso was torpedoed.
2. Fuso sheered out of line and slowed down.
3. Fuso turned around.
4. Fuso exploded and broke into two pieces.
5. Both pieces burned with a very notable fury.
6. Both pieces floated for an extended period before sinking.
That’s it. We know little about what the Fuso’s damage was, or why she exploded, or what shape she was in after the explosion (although, obviously, she was not in ship shape, so to speak ....)
It is at this point that some conjecture must enter. Tully’s description of the probable damage to the Fuso as a result of the torpedo(es) can be used as a baseline:
As for the hit or hits, a likely outcome of strikes amidships would have been flooded boiler and/or machinery spaces, as well as the possibility of starting a fire near the amidships magazines. The blows likely killed communications, and possibly knocked out all the starboard machinery, thereby cutting the battleship's speed drastically. Ban Masami swung his vessel out of line, probably to clear the formation to prevent a collision as a result of his sudden loss of speed.These are reasonable assumptions, based upon the evidence, but these are likely the only assumptions we can make here.
Remember the generally accepted narrative here is that the explosion was caused by a detonation of the Fuso’s midships magazines. This was likely caused by a fire, and, to be sure, there is evidence of induced explosions, as the Hutchins’ report of three detonations – “two faint and a loud snap” – suggests. The vast majority of the published histories of the Battle of Surigao Strait give this version of events.
But it is important to note that this version of events is itself based on an assumption – that there was a fire on the Fuso caused by the torpedo it. We’ll call it the “Fire Scenario.” Aside from the explosion itself, however, there is no evidence of a fire. The Mogami’s account of the torpedo hit gives no indication of a fire. The PT boats’ account of the explosion say she “burst into flames,” which suggests she was not already in flames, or at least not visibly in flames.
To be sure, fire aboard a ship is not always visible to the outside, but even if the fire is below decks, there are usually noticeable signs. Damage control will often open vents, with the goals of clearing the smoke (it could choke crewmen and damage control below decks) and lowering the temperature (if the temperature gets too high, injuries could mount and combustible materials ignite). Smoke can be seen even at night, as the reports of the smoke pouring forth from the Asagumo after she was torpedoed suggest.
If we go strictly on the available evidence, and try to minimize assumptions, two other scenarios emerge that might actually fit the evidence better than the Fire Scenario does.
The Barham Scenario
This scenario comes from the sinking of the British battleship Barham on November 25, 1941 by the German U-boat U-331 in the Mediterranean off Cyrenaica. Basically, the Barham was torpedoed, quickly took a severe list and exploded. Queen Elizabeth Class Battleship by Alan Raven and John Roberts was quoted describing the incident and its aftermath:
At 16.00 on 24 November 1941, the [battleships] Queen Elizabeth, Barham and Valiant, escorted by eight destroyers, sailed from Alexandria to cover cruiser operations against two enemy convoys reported to be making for Benghazi. On the following day the fleet ran straight into U331 which passed through the screen without being detected. From the center of the fleet the submarine fired four torpedoes at the second ship in the line, the Barham. Firing disturbed the submarine's stability and her conning tower broke surface. For several seconds this remained visible and after passing close down the side of the Valiant she disappeared beneath the sea and eventually escaped unharmed. Three of the torpedoes struck the Barham on the port side between Y turret and the funnel. She immediately took on a heavy list and after a pause at 40° this continued to increase until after four minutes she was on her beam ends. At this moment the after magazines exploded and vented through the starboard side and the upper deck. The ship disappeared from view in an enormous cloud of smoke and when this cleared she was gone. Captain G.C. Cooke and 861 officers and men were lost with the ship. Vice-Admiral Pridham-Wippell and 395 members of the crew were rescued.
Due to the rapidity of her loss the Board of Inquiry were unable to establish the reason for the explosion but it was thought that it might have been due to a fire in the port 4-inch magazines spreading to the main magazines. After the torpedoes struck the internal lightning and communication systems failed rapidly and no general orders were heard probably due to the failure of the broadcasting system. She was operating the correct degree of water-tight sub-division for cruising but the rapid increase in heel prevented any effective counter-measures to save the ship.
The Royal Navy battleship Barham sinking in the Mediterranean off Cyrenaica on November 25, 1941 after being torpedoed by the German U-boat U-331. The magazines of the Barham exploded seconds later. A British review panel attributed the explosion to a fire in the secondary magazines that spread to the main magazines.
I have not been able to find the report on-line, so it is difficult to say for sure, but it seems that the Board of Inquiry wasn’t too sure about this whole fire thing. There is no visual evidence of a fire; the smoke seen in the photograph comes from the stack. The accounts I have read of her sinking do not mention a fire. I do not know what evidence the Board of Inquiry saw without having the report in hand, but they may have assumed that since her magazines exploded, there must have been a fire. Which is what we have with the Fuso. In fairness to the Board of Inquiry, however, they may not have had much to go on, since the Barham sank within a matter of minutes.
While an exploding battleship like the Barham was not an everyday occurrence, it was not an isolated incident either. Wikipedia even has an entry on “exploding warships.” (Their take was that most of the incidents of exploding warships involved British cordite. It is unlikely that at this point in their war against the US and Britain, the Japanese were using British cordite.)
The Japanese seemed to be particularly vulnerable to the phenomenon. Tully documents what he calls the “HMS Barham at night.” This would be the sinking of the Japanese battleship Kongo. At about 3:01 am on November 21, 1944, the Kongo took two torpedoes from the US submarine Sealion. Unable to reduce her speed for damage control purposes because of the lurking submarine, Kongo lingered on for about three hours of progressive flooding, ultimately trying to make port for emergency repairs, before stopping and exploding just before dawn. Tully goes to some lengths to describe the battleship's ordeal. Kongo was in a convoy at the time, with Yamato and Nagato. She never reported a fire, only flooding. There is no evidence of a fire, aside from the detonation itself, which was apparently of the main ammunition magazines.
These would have been two instances where a battleship already heeling over and sinking exploded, for no apparent reason. Nihon Kaigun also had an incident all its own, where a battleship exploded without apparent reason or warning. That would be the Mutsu.
On June 8, 1943, the Mutsu’s No. 3 turret magazine exploded while the battleship was at anchor in Hashirajima. The detonation broke the ship in two. Though she sank in a rather shallow harbor, the battleship could not be salvaged.
There was a major inquiry as to why the Mutsu exploded. The mystery was never really solved. Initial suspicion that the blast was caused by the sanshiki-dan incendiary shells proved unfounded. According to CombinedFleet.com, after two months of work:
The investigation concludes that the explosion was "most likely caused by human interference". Some investigators think there was a ring of saboteurs, but the principal suspect is a disgruntled seaman gunner of turret No. 3 who had brooded over theft charges and was killed in the blast. The divers search for his body but it is never found. During the war, the belief persists that, somehow, he managed to escape.Ultimately, the Japanese decided to revise their procedures for handling explosives on their ships.
What does this have to do with Fuso? There is a hint that she may have been another “HMS Barham at night,” to use Tully’s phrase.
In Nishino’s account, he was informed by a lookout at a little before 3:30 am that they thought they spotted the Yamashiro “sinking.” As noted earlier, this would not have been the Yamashiro, but the Fuso. “Sinking” can mean any number of things, all related to a critical, irrecoverable loss of buoyancy.
It could have meant the Fuso’s explosion, except that the Fuso would not start exploding for at least another nine minutes. According to Mogami, the Fuso was listing to starboard after her torpedo hit(s).
Did Shigure see Fuso start to capsize to starboard? Could that have been a prelude to a catastrophic explosion like the Barham and the Kongo? If this was the case, could the Fuso share a common, as-yet-undetermined cause to her explosion as the Barham and Kongo? Maybe the munitions bouncing around as the ship rolled over? Maybe the same munitions issue that destroyed the Mutsu?
The problem with this theory is that the inherent unreliability of eyewitness testimony rears its ugly head. Nishino says his lookouts spotted what was actually the Fuso “sinking.” If Fuso was indeed “sinking,” as in rolling over to starboard, why did the Mississippi later see her fires blazing above her mastheads? Why was Shima’s force able to identify (or misidentify) the two haves of the wrecks as battleships? The implication in their statements (particularly that of the Mississippi) is that the pagoda was upright, that they at least gave the impression of a battleship.
How would the Fuso return to an upright position after exploding when she was already capsizing?
Further, how would the Fuso remain afloat after exploding and breaking into two pieces?
The only logical way to interpret these statements is to discount Nishino’s statement. Shigure did not see Fuso “sinking,” only at most listing, which is what Mogami described.
This leaves one possibility that has intrigued me for some time.
The Fuel-Air Scenario
On their way from Lingga Roads near Singapore to their destiny in the Sho operation, Kurita’s First Striking Force put in at Brunei, on the northwest corner of Borneo. Somewhat strangely, Kurita had taken tankers with him to refuel his ships. Borneo was one of the gems of the Southern Resources Area because of its oilfields, particularly those on the island of Tarakan, just off the northeast coast of Borneo, so this was like visiting Saudi Arabia and bringing your own gasoline. It doesn’t make much sense on its face, particularly given their severe shortage of tankers. Why would the Japanese do this?
Because they had been burned.
Four months earlier, Nihon Kaigun had deployed its entire carrier force to defend the Mariana Islands – Saipan, Tinian and Guam. The result was what Americans know as the Battle of the Philippine Sea. The alternate name is the “Marianas Turkey Shoot,” because of the slaughter of Japanese pilots by American air forces. The battle was an unmitigated disaster for Japan, even causing the fall of the Tojo government (not that all Japanese or even perhaps a majority of them considered this was a bad thing …) But the abysmal performance of Japanese pilots and the brutal efficiency of American air defense were not the only causes of this debacle.
Nihon Kaigun had sent its biggest, best carriers – Taiho, Shokaku, Zuikaku, Junyo, Hiyo – and a handful of smaller carriers – nine in all – into this battle. Taiho was supposed to be the best of them.
Brand new and considered to be “unsinkable” – where have you heard that one before? – Taiho was chosen by Admiral Ozawa as his flagship for the upcoming battle. She had an enclosed hurricane bow, an armored flight deck and other improvements. The Taiho incorporated many of the lessons Nihon Kaigun had learned from Midway, with one notable exception.
The US submarine Albacore had infiltrated the Japanese anti-submarine defenses and, after a fashion, managed to hit the Taiho with a torpedo at 8:10 am on June 19, 1944. CombinedFleet.com describes the damage:
The impact punches a hole in the hull which floods the forward elevator well and gives the Taiho a 1.5 meter trim by the bow, but she maintains speed at 26 knots. The forward elevator, which was raised for launching operations is jarred loose and falls two meters, disrupting take-off operations and the torpedo hit cracks the av-gas tanks underneath it as well. As a result, free gasoline mixes with the water flooding the forward elevator well and av-gas [aviation gasoline for the aircraft] vapor builds up in the space. Within a half-hour damage control has planked over the settled No.1 elevator and the remaining planes were launched.Historian William Y’Blood:
This torpedo, the only one to hit, struck the Taiho’s starboard side near the forward gasoline tanks. The ship’s forward elevator jammed and gasoline and oil lines ruptured. But the carrier’s sped slackened only one knot and no fires broke out. To the ship’s damage control officer the damage was only minor and repairs would be quickly accomplished.At least that was the plan.
[...] But now she was a time bomb waiting for the moment to go off.CombinedFleet.com adds some details and perhaps a clarification:
Clumsy attempts to ruptured fuel and oil lines and to pump overboard the fuel in damaged tanks had been made by the ship’s damage control parties. Large quantities of gas were spilled on the hangar deck as it was being pumped over the side. Then, an inexperienced damage control officer made a disastrous decision. In an effort to dissipate the fumes seeping from the tanks, he ordered the ventilating ducts opened. The effect was just the opposite of what he had planned; it only spread the volatile Tarakan petroleum fumes, and the equally dangerous avgas, fumes throughout the ship.
[T]he gas vapor builds in the closed hanger and enclosed bow area and becomes serious. Efforts to free the mounting vapor by knocking holes in the ship's side or to ventilate the hangar are made. ("ventilate may not refer to the actual ventilation system, but just the d/c efforts). At 1350 CarDiv 1's [Carrier Division 1 consisted of Taiho, Shokaku and Zuikaku) strike wave begins to return. With Shokaku ablaze and bow awash, all planes must land on either Zuikaku or Taiho. The gas vapor danger aboard Taiho is so great that most opt for Zuikaku; the terrible losses attacking TF 58 [US Task Force 58: the US carriers] having left the space to be accomodated. Possibly a few planes of Shokaku's as well as some of Taiho’s do land on her.The enclosed hangar – with no openings for ventilation or disposal of combustibles in an emergency – had been a problem for the Japanese carriers at Midway. It would prove to be a problem now.
At 2:32 pm (Y’Blood says 3:32; I have gone with CombinedFleet.com), the Taiho suffered a cataclysmic explosion. A spark somewhere in the ship had detonated the fumes. The armored flight deck was split open and blown upward like a mountain top. The hull was breached below the waterline. All power was lost and she went dead in the water. The sides were blown out of the hangar deck. She had ventilation now.
Fires raged out of control and explosions continued. No rescue vessels could get close to her. Oil from the ruptured tanks covered the water near the blazing Taiho and caught fire itself. Ozawa was forced to abandon ship and Taiho sank. Y’Blood and CombinedFleet.com disagree on the time, with the former going for 4:28 pm and the latter going for 6:28 pm.
Meanwhile, eerily similarly calamitous things were happening to one of Ozawa’s other carriers, the Shokaku.
At 11:22 am (Y’Blood says 12:20 pm), Shokaku was hit by four torpedoes from the US submarine Cavalla. Again, Y’Blood describes the damage:
[F]our torpedoes had actually slammed into the Shokaku at 1220.The big carrier slowed and fell out of formation. Flames raged through the ship and explosions tore her apart. The Shokaku's damage control personnel were better than the Taiho's and got many of the fires under control, but they could not contain them all. And all the while, the deadly fumes from ruptured gas tanks, and tanks carrying the Tarakan petroleum, were seeping throughout the ship.CombinedFleet.com:
[…] [A]t 1122 hit by three torpedoes [actually four] fired from USS Cavalla (SS-244) in the starboard side; two forward near the switchboard and generator room, and and one amidships. Large fuel fires are ignited in the hangar and No.1 boiler room goes off line. Carrier begins to list to starboard, and counterflooding to port is carried out, but overcompensates, giving her a port list. Meanwhile Shokaku continues to settle forward. Though damage control initially hoped to save her, the flooding forward and the fires intensify in the following hours. By 1210 has come to a halt when fires detonate an aerial bomb on the hangar, setting off volatile gases from a cracked forward tank. Large induced explosions wrack the carrier, and hope begins to fade.Tully, Parshall and Richard Wolff, in their determination that Shokaku was actually struck by four torpedoes, quote from NavTechJap Article S-06-3 dated January 1946:
Shokaku (CV-6) - Shokaku Class. Sunk 19 June 1944 during the Battle of the Philippine Sea. 1100 (approx.) She was west of the Marianas when struck by not more than three submarine torpedoes. One was close to the forward bomb magazines. Gasoline tanks were ruptured, and there was a fire of undetermined proportions. The fire was extinguished promptly, according to survivors, by closing all access to the spaces surrounding the gasoline tanks. Gasoline fumes, however, began to seep throughout the ship. Several hours later an enormous explosion caused her to disintegrate. It may have been her bomb magazines.Whether Shokaku was sunk by three or four torpedoes is irrelevant to the pattern that is emerging here.
The next day, a late afternoon US airstrike caught the remaining Japanese carriers barely able to defend themselves, so badly had their air groups been depleted. The carrier Hiyo was one of the targets hit. CombinedFleet.com tells her often-overlooked story:
One small bomb dropped by a plane from USS Lexington's Air Group 16 graze the foremast and exploded above the top of the bridge, showering it with fragments. […] Another bomb is repoted to have exploded on the flight deck. Just afterward six torpedo planes from USS Belleau Wood Air Group 24 drove in for an attack (U.S. records say it was four planes led by Lt (jg) George Brown). Two were shot down, and three dropped their weapons too far away, but one badly hit and burning TBF "courageously closed to most favorable angle and range" and dropped his torpedo which struck the starboard engine room. The burning plane then hurtled by the island and crashed into the sea. [footnote omitted.] With the starboard engine flooding, white steam belched out of Hiyo's funnel and she began to lose speed rapidly, but continued to steam on her port shaft. Her sister carrier Junyo closed for a brief time, but was urged to proceed on. Fires had broken out, but were believed to be under control and the list checked. The original course was resumed and the Hiyo commenced to retire with the others. However, nearly two hours after the initial hit, there was tremendous explosion that erupted from the port quarter. A torpedo from an enemy submarine was believed responsible. (Note 2). This explosion damaged the main switchboard panel and stopped all power generation. Leaking gas was set off and flames engulfed the whole rear of the ship. […] The Hiyo began to settle by the stern and list to port, which was indicative of the force of the major explosion that had ripped through her earlier. (emphasis in original)They note:
To date, this Japanese claim of a submarine torpedo hit on Hiyo had been confusing, and imagined perhaps to be the result of the traumatic experience of the sinking of both Taiho and Shokaku by submarine just the day before. However, IJN official sources always credited a submarine torpedo […] Instead, what clearly happened was a massive induced explosion that doomed salvage efforts and fatally wounded the vessel. This makes Hiyo one of three Japanese fleet carriers sunk by the same combination of petrol tank vapor and induced explosion within a 48 hour period.Let’s restate that: in two days Nihon Kaigun had lost three irreplaceable, top-of-the-line aircraft carriers to fuel-air explosions – fumes given off by ruptured oil and gasoline receptacles that were detonated by a spark or an existing fire.
The Japanese believed that the oil from Tarakan was the prime factor in these explosions, that but for the vapors given off by this brand of oil, these ships could have been saved. To be sure, not all crude oil is alike – for instance, Saudi crude oil is easier to refine that oil from the North Sea or Venezuela. The Japanese in a do-or-die operation did not want to risk using the Tarakan fuel or anything from Borneo, so they brought fuel from points south.
What does this have to do with the Fuso? A fuel-air explosion as the cause for the battleship’s catastrophic explosion is more consistent with the available visual evidence than either the Fire Scenario or the Barham Scenario.
What could have happened with the Fuso is the torpedo hit knocked out the starboard machinery – the engines on the starboard side. It could have caused a leak of fuel oil in the area. So busy was damage control trying to control the flooding or repair the engines that the vapors may have taken a lower priority on their to-do list. But a spark – somewhere, not seen by the Mogami or anyone on the outside – set off the gases. The resulting explosion could have been small, but started enough of a fire to detonate the main ammunition magazines.
But hadn’t the Japanese taken this into account when they refused to take on the Tarakan fuel at Brunei? They had tried, but Tarakan fuel is not the only fuel that can give rise to fuel-air explosions. The aircraft carrier USS Lexington, for example, was lost at the Battle of the Coral Sea because accumulated fuel vapors were detonated below decks.
The US aircraft carrier Lexington sufferes a fuel-air explosion at the Battle of the Coral Sea, May 8, 1942. The carrier had suffered damage from Japanese air attacks earlier in the day. The damage was under control, but ruptured fuel tanks led to the buildup of vapors below decks that were ignited by a spark of unknown origin. The explosion reignited the fires and led to the loss of the carrier.
Unfortunately, while I believe this scenario fits the available evidence very well, it remains largely conjecture. The evidence to support it is slim at best and based on interpretation. The Hutchins reported three detonations – “two faint and a loud snap.” The faint explosions may not have been ammunition cooking off, but fuel-air explosions setting of a fire, which ultimately did set off the ammunition. The PT boats said the Fuso "burst into flames [about 3:45 am]." But “bursting into flames” is not necessarily an explosion, and could suggest a chemical element to it. The sheer fury of the fires that engulfed the remnants of the Fuso also suggest a chemical element. Finally, the Kanihaan PT’s went to the position of the Fuso’s stern and found no ship left, only fires, give a strong indication of burning fuel on the water, but it gives no indication of when or how this fuel was spilled.
So, it is nothing but a supposition that happens to fit the evidence. But it is a theory that I would hope someone with more expertise than myself could explore.
That leaves but one more loose end to tie up here, at least as much as it can be tied.
Did the Fuso break in half?
It may sound somewhat obvious to say that a ship breaking into two pieces breaks in half. One can say that people are symmetrical by nature. That was my first assumption when I read about the Fuso. That is actually what I believe now. Admiral Mumma’s assumption was the opposite. Let’s repeat what he said:
It is our conclusion that it is well nigh impossible for the Fuso to have broken into two nearly equal parts because of her very rugged and damage resistant structure. The USS Arizona did not show any evidence of hull failure in the area enclosed by the armor belt, even though a massive magazine explosion had occurred.I am singularly unimpressed by this statement. In fairness to Mumma, as Tully points out, he was going by what they knew back then. Research over the years since then has revealed much more. Willmott calls the Fuso-class battleships “poorly compartmentalized,” which suggests even the armor belt (a heavily armored portion of the lower hull that does not usually include the bow or the stern) could have been vulnerable here.
It is however considered possible that the Fuso may have lost her bow as a result of torpedo damage. Although our war experience does not include this type of failure in battleships, several cases exist where cruisers suffered this type of damage. In the case of the USS Helena (CL-50) the bow section remained afloat for more than twelve hours.
It is probable therefore that if other evidence indicates the presence of two floating bodies this can best be explained by the separation of the bow from the main hull of the battleship.
Mumma’s theory requires a very strained interpretation of the evidence:
1. The movement of the Fuso’s stern
According to Tully, American radar tracks show the stern section of the Fuso swinging to port, to the southeast, on a diverging line from the other half. By 4:00 am this section had opened the range between the pieces to 2,000 yards – more than a mile – after which its position remained fairly constant relative to the bow.
If the stern retained propulsive power, it hints that the break was further forward, possibly only including the bow. But Tully pooh-poohs the theory that the stern retained propulsive power. I tend to believe it, but I am a romantic at heart.
2. Shima’s force misinterpreted what they saw.
Remember that Shima’s torpedo officer, Mori said he “saw two fires, two ships burning, very big ships,” and went on to say:
When we first saw that fire, I judged it was about 20,000 meters from their position. Although we knew they were Japanese vessels on fire we did not bother with them, just progressed. […] We thought it was two battleships, but when we arrived at Manila we heard that it was one battleship (Yamashiro) and three destroyers close together instead of two battleships.Now, granted, Shima’s force did misinterpret what they saw: they thought the two halves of the Fuso were two separate battleships, but that is far more understandable under the circumstances than mistaking a bow for a complete ship.
For Mumma’s theory to be true, Mori and his shipmates must have been using the size of the fires, the distance between the two halves of the Fuso (over a mile) and his knowledge that Nishimura had two battleships to determine that what he saw were two separate battleships. While the fires could definitely have made the hulls in question seem larger, that is simply too many misinterpretations for experienced seamen to make.
Shima’s forces, the Louisville and PT-323 made distinctions between the fires and the remnants of the Fuso itself. Mori called the ships “very big” and identified them as “battleships.” Louisville fired on "what seems to have been the bow" of the Fuso, but said it was large, which hints it was more than just the bow. Mississippi’s report strongly suggests that the Fuso was upright immediately after the explosion. Mori and his comrades must have seen something – the pagoda? The stack? The mainmast? – that suggested what they were seeing was a battleship. The fires could have masked what remained of the hull, but the identification as a battleship – one of their own battleships that they should have easily been able to recognize – is a major indication that features distinctive to Japanese battleships (as opposed to Japanese cruisers or destroyers) such as the pagoda superstructure were recognizable.
On top of that, it defies logic and basic physics to suggest a torpedo hit amidships could by itself lead to the loss of the bow, not when you have an ammunition magazine in the area, between the area of the hit and the forward turret magazines.
That said, while I believe Mumma’s theory is extremely unlikely, it cannot be ruled out. So much was misinterpreted on this night – see.,e.g, Nishino, Shigeru.
Unfortunately, only a dive to the wreck of the Fuso could help provide insight, and given the shape the wreck must be in after fires that evoked images of a blast furnace, maybe not even that could solve these riddles of history.
But even without the knowledge that it will answer the questions – any of these questions – such an effort is worth doing.
As the World War II generation draws to a close, such an effort can only serve to remember and illuminate the sacrifices made by the servicemen of both the United States of America and Japan.
UPDATE -- Ship in foreground of Surigao Strait picture has been identified as light cruier USS Denver.
Previous:
Part One: The Battle of Surigao Strait
Part Two: Was the Fuso the battleship that was torpedoed and dropped out?
Part Three: Why did Nishino believe the Yamashiro had dropped out instead of the Fuso?






