HMNZS Moa (Solomon Islands — 150 fsw)

Background

The HMNZS Moa (T233) was a Royal New Zealand Navy “Bird-class” minesweeper (there were only three and they were named after New Zealand native birds – the Kiwi, Moa, and Tui). She was laid down in March 1940, launched on 15 May 1941, and commissioned on 12 August 1941. She was 168 feet long and had a beam of 30 feet so it was a relatively small warship.

For armament, she had 1 x 4-inch gun, 1 x QF 2-pounder gun, 1 twin Lewis gun, and 40 depth charges for her primary mission which was minesweeping and anti-submarine warfare.

The Moa was a somewhat pedestrian vessel in terms of warships; however, she has a VERY interesting history and was instrumental in the sinking of the Japanese I-1 Submarine (which I will write a separate post about) — which, in turn, had a big impact on the war in the Pacific.

The Japanese I-1 Submarine Incident

In 1942, the Moa was deployed to the Solomon Islands. On the night of the 29th-30th of January 1943, she was patrolling with her sister ship the Kiwi off Kamimbo Bay when it detected a vessel about 3,000 yards away which was identified as a submarine. The Kiwi altered course for interception while the Moa maintained her heading and directed the Kiwi based on the Anti-Submarine Detection Investigation Committee (ASDIC) which was the precursor to modern day sonar.

The Kiwi could literally see the outline of the I-1 submarine underwater and dropped 6 depth charges on her. Those depth charges knocked out the I-1’s port electric engine and flooded her aft stateroom. The Kiwi then dropped another 6 depth charges which disabled the pumps, the steering engine and the port shaft. The control room was partially flooded from a high-pressure manifold rupturing which then resulted in the main switchboard shorting and the lights going out. The ship sank way beyond her rated depth and started to leak which caused the captain to blow the main ballast tanks.

After the I-1 reached the surface, the Kiwi and the Moa started to fire on her. The I-1 fired back and the three were in an all-out gun battle. The Kiwi then changed course to literally ram the I-1 submarine! She delivered at least three ramming runs which severely damaged the submarine. The order to Abandon Ship rang out on the I-1 and she was badly flooding.

I will leave it to the post on the I-1 Submarine to explain the rest of the story, but suffice it to say that the Moa and the Kiwi were instrumental in sinking the submarine through gunfire and ramming her. The information salvaged from the I-1 was vital to our understanding of the Japanese plans.

The Moa Sinks

In April 1943, the Moa was patrolling and providing escort duties around Guadalcanal. On April 7th, the Japanese launched the “I-GO” operation to destroy bases and ports if the Allied forces in Guadalcanal. The Moa was refueling the night of the 7th when the Japanese launched an air attack as she sat tied to the refueling vessel. The Moa opened fire but was hit by two 500-pound bombs with one going through the captain’s captain narrowly missing the captain who was resting during the refueling. The second bomb exploded in the boiler room causing massive damage.

The Moa sank in only 4 minutes with five people losing their life and another 15 wounded.

The Moa sits between 120 and 150 feet deep.

Highlights of the Moa wreck include the depth charge racks at the rear and the gun near the forward area. There is apparently a smaller 20mm Oerlikon gun that is out in the sand with the rest of the bow buried in sand. So, of course, I had to go look for it and then got a bit lost on the way back to the main part of the wreck as visibility was not great. Unfortunately, a purse seiner dragged an anchor across the superstructure which ruined it. This ship has also been salvaged but the prop wasn’t salvaged because it was made from iron and not bronze.

The Moa is the only New Zealand Naval ship that can be dived as a result of being sunk by enemy action.

Photos

As mentioned, the visibility wasn’t great but I did manage to get a few decent photos of the wreck.