© 1997 Anthony P. Tully
Posted April 1, 1997


The NACHI ~ MOGAMI Collision: A Study in the Fragility of History

To readers versed in the battle of Surigao Strait (25 October 1944), the story of the collision between the two Japanese cruisers MOGAMI and NACHI is a familiar one. However, it may come as a surprise (as it did to the author) to learn that the published historical record to date on the subject has been faulty, even inaccurate. This results in a distortion of the event that becomes noticeable when examined closely, but otherwise remains subtly hidden. To understand how this is so, and to appreciate the purpose of this article, it is best to begin with the story as it has been invariably rendered to date. For example, in S.E. Morison's LEYTE, Vol XII of the History of U.S. Naval Operations in W.W.II on page 233 appears the standard account. Flagship of Vadm Shima Kiyohide's Second Striking Force, the NACHI was rushing to the supposed aid of the ill-fated Nishimura section of Kurita's fleet when she sighted the blazing MOGAMI, one of the few survivors of Nishimura's force. Morison writes:

"Presently burning MOGAMI was encountered. Believing her to be dead in the water, Captain Kanooka of NACHI turned to course 110 to clear, but MOGAMI was actually moving slowly south and the two heavy cruisers collided at 0430. NACHI's stern was badly damaged, there was some flooding and her speed was reduced to 18 knots."

This story receives some enhancement in Edwin P. Hoyt's popular and well-sourced LEYTE GULF, where on page 242 the NACHI collision is discussed:

"They [NACHI's officers] ascertained that it [the burning cruiser sighted] was the MOGAMI, not dead, but moving very slowly southward. And as the attack proceeded, and the cruisers changed course to launch the torpedoes, [Admiral Shima] ordered right rudder, not knowing that the ship ahead was moving.....On came the Shima cruisers, at 26 knots,and on limped the MOGAMI directly into their line of approach.`We turned rudder full to starboard', said Commander Mori. But it was too late. The MOGAMI's bow crashed into the NACHI's port quarter at an angle of about 10 degrees. The ASHIGARA was luckier; she managed to evade by swinging to the outside, but the NACHI caught it squarely. The knifing bow of the MOGAMI sliced through the shell and into the anchor windlass room which flooded, and then into the steering room which began to flood. Bells and sirens screamed, and the NACHI's speed fell immediately to 18 knots."

Both of these accounts clearly indicated that the MOGAMI had plowed into NACHI's quarter, causing some flooding, and speed reduction to 18 knots. The mention of flooding in the steering room reinforces this impression. In any case, the MOGAMI and NACHI collision is usually described similar to one of the two quoted accounts above. However, in the RISING SUN by John Toland, there appeared an interesting variant:

"...But as he approached, Shima saw to his surprise that MOGAMI's prow had a wake. She was bearing down at almost 8 knots knots on a collision course.`Hard starboard!' he shouted, but the blazing MOGAMI moved straight at NACHI and there was a jarring crunch....The two ships drifted slowly as if locked together, then NACHI cautiously turned left and the two ships parted. MOGAMI continuing south. The port side of NACHI's prow was gone and the engineers reported top speed would be reduced to 20 knots."

The author was immediately struck by the mention of damage to the "portside of NACHI's prow". Though not conclusive, it suggested that NACHI had HIT MOGAMI, and not MOGAMI hit NACHI, which was the tenor of the prior accounts. Curiosity was naturally piqued, and it was resolved that some time on the next research trip to Washington D.C. would be spent trying to shed light on this discrepancy and contradiction. In time, the truth was recovered and how the paradox came to be was explained.

The explanation and story that follows is a telling lesson on the fragility of accepted history and how easily simple oversights can lead to a perpetuating, compounded error and incomplete story. It is also a fascinating tale on how history comes to be told, and reveals the challenges and pitfalls involved in the process of transforming dry official records into readable, coherent story.

At the Operational Archives of the Naval Historical Center in the Washington D.C. Navy Yard were found key pieces of the puzzle. One was an account written by Lt. Fukushi, a POW and MOGAMI survivor, and the other was MOGAMI's own Detailed Action Report, as translated as part of the preparation for S.E. Morison's volumes. Fukushi's account even included a hand-drawn diagram of the collision! It clearly showed - in rough form - the NACHI impacting AGAINST the MOGAMI's starboard forward. This was a patent and flat contradiction of the accounts quoted above that indicated that MOGAMI impacted NACHI's port quarter. At first,the other errors and questions about the Fukushi account, raised doubts as to its reliability. If it was true, there was an unresolvable contradiction. However, the MOGAMI's own Action Report (JD-9) was unequivocal. The Fukushi account was correct---for the MOGAMI Action Report also stated that NACHI rammed MOGAMI's starboard bow (adding thedetail that it was abreast No. 1 8inch turret), and not the other way around.

With the MOGAMI's account examined, it remained to check that of the NACHI. This was stymied by the lack of a Second Striking Force Action Report, or NACHI Battle Report. However, the NACHI's War Diary for 1-5 November 1944 was found and its translation arranged. As hoped, it indeed described the damage resulting from the collision in specific terms (see below) and stated that the port bow plates were torn and the anchor windlass room flooded. The consensus was clear: As far as the primary Japanese sources were concerned, NACHI hit MOGAMI - not vice versa. What was going on?

Another primary source, INTERROGATIONS OF JAPANESE OFFICIALS, contained a report by Shima's torpedo officer, Mori Kokkichi on the NACHI. Though he did not describe the location of the collision, he did confirm it came after NACHI turned hard right, and that the two cruisers collided at an "angle of about 10 degrees." This suggested a picture hard to square with a MOGAMI slice to the stern, but fitted well with NACHI buckling her bow in a "skidding" slam into MOGAMI.

Further research found that the Monograph of Philippine Naval Operations, a translated document prepared by Japanese officers for the occupation post-war, discussed the NACHI/MOGAMI collision. It gave no details of the collision, but said that NACHI's "chain locker [windlassroom] was flooded" and her effectiveness impaired. Since many vessels have anchors on both bow and stern, this particular clue seemed unhelpful. It did demonstrate that the Hoyt quote had a firm basis when it added the windlass room flooding detail.

At this stage the contradiction seemed insoluble, and the author felt compelled to make an arbitrary judgement. Given the strength of the primary sources for it, the clear conclusion was that the the Japanese sources were correct and the others were mistaken. The NACHI rammed MOGAMI, not the reverse, and the damage suffered was to the NACHI's bow,not the stern. It was then that a final comprehensive check at last uncovered the key to the riddle and solved the mystery of the paradox and contradiction.

It was known that S.E. Morison's LEYTE section on Surigao was drawn in large part from the WAR COLLEGE ANALYSIS VOL. V on the same subject. This was clearly stated by Professor Morison. Upon looking up the pertinent section describing NACHI's damage after the collision, there came an astonishing revelation - it said: "....her stem was heavily damaged, her anchor windlass room flooding, and there appeared to be seepage into the steering room."

The paradox is now solved, and the answer is as much a warning as it is a revelation. The entire and steadily increasing distortion over the decades of published works had apparently all originated with the substitution of a SINGLE WORD. Somehow in editing or transcription, NACHI's `stem' (bow or prow) became NACHI's `stern', completely destroying the original meaning! Anyone reading the faulty rendition would be forced to take the steering room "seepage" as additional confirmation of a stern impact. However, the context makes it clear that it was ancillary damage, perhaps from vibration.

It seems certain that Professor Morison was closely referencing the WAR COLLEGE ANALYSIS, and that this is a genuine typographical slip, not error in sourcing. However, with `stern' substituted for `stem' even the overt red-flag clue of `chain locker flooding' was not appreciated. Subsequent writers faithfully repeated the fantail-impact fallacy, and threw in the other flooding details for good measure. On the other hand, sources written from the Japanese point of view, like Toland's RISING SUN, naturally just gave the story as the Japanese had it, but suffered inevitable distortion when combined with western accounts.

On reflection, the above exploration sounds a cautionary note to all historians and makes clear that even events long taken for granted may conceal hidden questions. Some new works may be only "rehashing" a past error, on the other hand, "old" unpublished official sources may be more accurate and valuable than realized and worthy of a closer look. No doubt, in most cases, even the most heavily written about topics of history (Pearl Harbor for example) can still provide fresh discoveries,additions, and even corrections in the record. This is even more true for subjects like the Imperial Japanese Navy that suffer from a dearth of fresh discussion, integration of sources, and informed questioning of the received published record. Existing printed sources must be double-checked if possible, if a clear inconsistency or contradiction isfound.

This is in no way a negative; like archaeologists at their site,it simply means there is always just a little bit something new for the next historian of a particular subject. Riddles to solve, either old and neglected, or new and unrecognized (In the future, I hope to compose and post more examples of both). Of course it is possible to suggest that even if this is the case, why bother? The answer to that is easy. That would not only be remiss and lazy scholarship lacking challenge,but not even a fraction as rewarding or fun.

For those interested in the full story, below is presented for what is believed to be the first time, the apparent true circumstances of the NACHI's collision with MOGAMI with some rare details from the aftermath.


At 0420 25 October 1944 Shima's Second Striking Force (2-YB) was proceeding north up Surigao Strait barely a half-hour behind thejust-decimated `Section C' of Vadm Nishimura Shoji and battleshipsYAMASHIRO and FUSO. At this time, NACHI's radar made contact on what appeared to be enemy ship, just to starboard of dead ahead. Vadm Shima ordered a torpedo attack from the cruisers while the four destroyers with them charged ahead, and at 0424 NACHI and ASHIGARA swung right to course 090. At 0427 both cruisers commenced firing a total of eight torpedoes. While doing so, the burning MOGAMI was seen to the north. To clear the hulk and to avoid being spotlighted in its glare, NACHI turned 20 degrees to starboard.

She had just settled on course 110 when it was suddenly realized that MOGAMI was not dead, but making close to 8 knots on a southward course straight for Crudiv 21. Admiral Shima ordered "hard to starboard" and the engines stopped. The NACHI veered right, but her momentum carried her `sideways', almost like in a skid,straight against the MOGAMI at 0429. By the time of the collision,Shima's evasion had brought the two cruisers nearly side by side, so that they impacted at a shallow angle of "about 10 degrees". NACHI's port bow slammed against MOGAMI's starboard forward, in the vicinity ofthe No.1 gun turret.

The impact bent the prow, smashed the No. 2 HA mount on NACHI's port side, and gouged open a 15 meter long rent in the waterline of the port bow abreast the capstans. After a moment of hasty megaphone conversation between the two bridges, the NACHI pulled clear, and immediately flooding began through the gash in the port bow. The chainlocker was flooding fast, and there appeared to be seepage in the steering room as well. Chief Engineer Kawasaki reported speed had to beheld to less than 20 knots to avoid strain, but the flooding was soon under control.

After the collision, both cruisers joined the other Japanese ships in the hard drive to escape the trap of Surigao Strait. Though both survived the night, neither would see the homeland again. MOGAMI was sunk before noon of the same day of the collision, after a gallant struggle to survive repeated sea and air attacks well documented in her Action Report. As for NACHI, she proved only slightly longer-lived. She survived the Battle of Surigao Strait, and with ASHIGARA proceeded to Coron Bay. On 27 October NACHI sailed to Manila. During an air-raid on the 29th she received a bomb hit on the aircraft deck, but damage was minimal. She entered No. 103 dock and draining of her flooded bow and repair of the rent plates was completed on 2 November. She left drydock and waited off Cavite for orders, being assigned to the ongoing TA reinforcement operations to Leyte.

However, then the fate NACHI narrowly avoided at Surigao caught up with her. On 5 November, Halsey's TF 38 hit Manila with four successive strike waves. Admiral Shima happened to be ashore,but NACHI got underway after the second wave, seeking to dash to the safety of the open sea. But the third wave caught her at 1250 between Manila and Corregidor in the middle of the bay and immobilized her with bomb hits and torpedoes in the starboard boiler rooms. The AKEBONO was dispatched to the stalled cruiser'srescue, only to be caught by the arrival of the fourth attack wave. This one pounced on hapless NACHI, and Shima watched as his flagship was blown apart and sunk at 1445 by five aerial torpedo hits. Lost with her was 807 officers and men, among them the luckless Captain Kanooka Enpei, Shima's CoS Cdr. Matsunaga Chichara and seventy-four of the Fifth Fleet staff. Barely 220 survived the blast and subsequent strafing. The cruiser's would-be rescuer AKEBONO in turn was hit by two bombs and set afire, but was dragged to temporary safety ashore with a loss of one officer and 23 men killed and 3 wounded. It fell to KASUMI and USHIO to rescue the NACHI's men.

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