USSBS: Interrogations of Japanese Officials --

Interrogation of: Vice Admiral OMORI, S. IJN; Commander-in-Chief. RABAUL Assault Force, 15 October 1943-15 November 1943.

Detailed account of Japanese operations at the Battle of EMPRESS AUGUSTA Bay, 2 November 1943, resulting in sinking of SENDAI (CL) from shellfire and HATSUKAZE (DD) from collision. Minor damage to HAGURO, MYOKO (CAs), SAMIDARE and SHIRATSUYU (DDs). Japanese attempt to stop U.S. landings at EMPRESS AUGUSTA Bay, during BOUGAINVILLE Occupation, thwarted by U.S. cruiser-destroyer action.

Establishment of bases in BOUGAINVILLE Area accelerated neutralization of RABAUL. Losses sustained in attempt to hold southern perimeter seriously effected defense of the Central PACIFIC Area.

Q. Give a description, including ships present in the Battle of EMPRESS AUGUSTA Bay, 2 November 1943.
A. Our operations during that period commenced on 31 October. The ships that were employed varied slightly due to arrivals and departures from RABAUL. It was one of our weak points because we were not able to train together. However, it was necessary because we had to maintain a continuous supply line to RABAUL.

At 1000, 31 October, I received orders to get underway to intercept an American Task Force that had departed GUADALCANAL and was steaming up the SOLOMON ISLANDS. We did not know its destination but it was my opinion that it was SHORTLAND ISLANDS. We got underway at 1500, 31 October and proceeded down ST. GEORGES Strait towards the TREASURY ISLANDS. The following Eighth Fleet ships were present:

Two observation planes were sent out from the MYOKO and one from HAGURO. They searched for the U.S. ships but due to bad weather were unable to find them. The planes returned to BUKA that night while the ships retired toward RABAUL at slow speed.

At 0030, 1 November, we received a report that American ships were near BUKA, so we turned to the north to intercept them. By the time that we approached SAND Island we had no further contact report, so turned northwest again, returning to RABAUL and anchoring at 0900, 1 November.

Immediately upon returning to RABAUL, headquarters there notified me that American forces were landing at Cape TOROKINA. I was then ordered to take a force and make a counter-landing at MUTUPINA Point Wand near TORKO. 1000 military personnel were then being loaded upon 5 destroyer transports. At 1500, 1 November, I got underway with the following ships

After reaching ST. GEORGE'S Channel I received a despatch that there was a delay in loading the military personnel, so was forced to wait until 1830 before all ships rendezvoused. Due to submarine activity in this area I did not like this delay. Furthermore, it later affected our operations because the destroyers were old types which

limited our speed. This prevented us from regaining the time. As soon as all ships joined up we proceeded on course 160 degrees at 26 knots. Just after leaving ST. GEORGE'S Strait a U.S. submarine was sighted. In order to avoid it, we took a course to the south which caused additional delay in reaching our destination. The three reconnaissance planes which we had launched the day before came out from BUKA and gave us cover and search during the passage.

1 November

1920: SENDAI attacked by one U.S. plane about 6° 30' S, 153° 30' E. No damage received. Apparently a large search plane, type not remembered. The original plan was to land the troops before dawn, 2 November. In view of the initial rendezvous delay, the additional delay due to avoiding the submarine, the limiting speed of the destroyer transports 26 knots, and the fact that we were sighted by the American plane, I recommended that the counter-landing not be attempted, but that our combatant ships attempt to destroy the American transports unloading in the vicinity of EMPRESS AUGUSTA Bay.

2230: Approval of plan received. Five destroyer transports returned to RABAUL. The remaining ships increased speed to 32 knots and proceeded to a point south of SAND Island.

2330: HAGURO attacked by U.S. plane off Cape MOLTKE. One bomb hit received amidships. Opened up side plating and reduced speed of formation to 30 knots. Due to darkness, the type of plane was undetermined.

2340: HAGURO reconnaissance plane sighted an American Force consisting of 1 cruiser and- 3 destroyers about 50 miles from the beach halfway between TORKO and MOLTKE.

2350: Changed course to engage U.S. Force.

2400: Just after changing course information was received that reconnaissance plane had dropped flares over EMPRESS AUGUSTA Bay and found many transports unloading troops.

Changed course again towards EMPRESS AUGUSTA Bay to engage transports.

2 November

0045: SENDAI sighted U.S. Force of 1 cruiser and 3 destroyers about 10 km. off port bow. Eighteen torpedoes were launched by the SENDAI and its destroyers. Changed course 160° to 180°. Received report that 2 torpedo hits had been made.

0050: U.S. ships commenced firing. SENDAI received many hits, thought to be from CA's, and became unnavigable. In avoiding fire of U.S. ships, the destroyers SAMIDARE and SHIRATSUYU, which were with the SENDAI, collided. The collision occurred while in a turn just after firing torpedoes. Due to the damage received in the collision, these two destroyers were only able to navigate at 14-15 knots. Since they could not maintain sufficient speed in combat, they turned in toward the beach of BOUGAINVILLE, then proceeded back to RABAUL arriving there at 1300, 2 November.

0100: Just after collision, SAMIDARE attacked by gunfire from U.S. destroyer. 3 hits received. Not much damage.

U.S. Forces still not definitely fixed in position. MYOKO fired starshells but were apparently duds. No illumination resulted. MYOKO under fire of U.S. ships. HATSUKAZE (DD) also under fire, turned to the left to avoid, then in turning right to regain position in formation collided with the MYOKO. MYOKO. apparently cut HATSUKAZE in half. One portion floated along port side of MYOKO damaging main deck structure and tearing off 2 torpedo tubes.

HAGURO received six 6" hits. 4 of them were duds. One man killed. 5 men wounded. Minor fires started.

Due to collision and general evasive action, Japanese force now separated into three distinct groups: Fifth. Cruiser Squadron (MYOKO and HAGURO) to the southwest, Tenth Cruiser Squadron (AGANO and 3 DD) in the center, Third Destroyer Squadron (SENDAI and 3 DD) to the northwest.

0113: MYOKO (F) sighted U.S. Force for first time bearing 080° T. CruDiv 5 changed course from 180° to 160° to close range. Opened fire on U.S. Force.

0120: MYOKO launched 4 torpedoes. HAGURO launched 6 torpedoes at U.S. Force.

0127: Received report that 1 torpedo hit leading U.S. cruiser, 2 torpedo hits on second U.S. cruiser, 2 torpedo hits on third U.S. cruiser. Shell fire hits also reported on U.S. Force.

0128: Changed course to 180° T.

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339

0137: Issued order for all ships to retire to RABAUL. This decision was based upon several factors. The definite composition of the U.S. Forces was never established. The analysis of reports indicated that there were at least 7 heavy cruisers and 12 destroyers opposing us. I had lost one cruiser by shell fire, one due to collision and two additional destroyers out of action due to collision. The MYOKO had lost 30% of its torpedo tubes. Our formation speed was reduced to 26 knots due to bomb damage of the HAGURO. We had exhausted our supply of flares. Aircraft flares did not seem effective. The HAGURO had received six 6" hits although four of them were duds. In addition I felt that I should retire by 0100 in order to be outside of the radius of dive-bombers by dawn. This radius was considered 250 miles.

0140: Cru Div 10 launched 8 torpedoes at leading cruisers but it was at extreme range.

0154: Cruiser Division 10 reported 1 torpedo hit on a U.S. cruiser.

0200: SENDAI sank.

1300: Arrived RABAUL.

1500: RABAUL attacked by about 200 B-25's. Attack directed at airfields and installation. No ships reported lost or damaged.

1 (CL) SENDAI sunk from gunfire. 20 men killed, 300 missing. A number of men reached BOUGAINVILLE on rafts. I also ordered a submarine to the area. The submarine rescued some personnel including the commanding officer. About 20 of the Third Destroyer Squadron Headquarters Staff personnel were killed by shellfire.

1 (DD) HATSUKAZE sunk as result of collision. All personnel lost.

2 (DD) SHIRATSUYU and SAMIDARE damaged due to collision.

1 (CA) HAGURO received minor damage from shell fire.

1 (CA) MYOKO received one 6" hit from cruisers, and structural damage from collision.

Q. What caused your unusual number of collisions?
A. Lack of training in night operations. By the time of this battle we had lost about 40 destroyers and about 6 cruisers from the fleet that operated in the RABAUL-SOLOMNS Area. In order to maintain our bases we had to substitute ships from other fleets. These ships never had an opportunity to train together. Sometimes, as in this action, they would report in the afternoon and be engaged in an action the same night. We had some modified aircraft radar sets in this action but they were unreliable. I do not know whether the sets or the operators were poor, but I did not have confidence in them.

Q. What effect did this action have upon your plans?
A. I do not think that this action by itself was too important. However when considered with the other actions of this campaign, it appeared to the to be the climax of your advance up the SOLOMON ISLANDS. This advance was a cleverly conceived strategic plan which we were not prepared to counter in force.

After this battle you were able to establish bases on BOUGAINVILLE which permitted you to maintain constant air assault upon RABAUL, which prevented us from providing support and air cover to our bases on NEW GUINEA and NEW BRITAIN.

We had thought that your counter-action against the EMPIRE might come from the south. We planned to use RABAUL as a main point of the NEW GUINEA-BISMARK-SOLOMON perimeter defense. By your constant advancement of airbases through the SOLOMONS you were able to neutralize RABAUL without actual assault. During 1943 we attempted to hold this line at all costs. It was very expensive. We lost most of our best pilots, many valuable ships and many well trained military personnel that we were unable to replace.

5S	(CA) MYOKO (F), HAGURO. Vice Adm OMORI.
10S	(CA) AGANO (DD) HATSUKAZE WAKATSUKE NAGANAMI
3rd	(CL) SENDAI (DD) SIGURE SHIRATSUYU SAMIDARE 5DD (Army personnel transports)

EMPRESS AUGUSTA BAY, 2 NOVEMBER 1943