Chuuk Lagoon · Micronesia · Wreck
Unkai Maru
A photogenic bow gun and coral-covered masts
Photo: montereydiver · CC BY 2.0
Unkai Maru is an English-built steamer of 1902, once the S/S Venus, that ended its career in Japanese service and on the floor of Chuuk Lagoon. The 110 m (360 ft) wreck is known for its photogenic bow gun and for coral growing on its masts, which rise to within 9 m of the surface.
Also known as Unkai Maru No.6.
Where it is and how deep
7.3167° N, 151.7500° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The masts reach up to about 9 m (30 ft) and carry good coral growth. The bow gun is the photogenic centrepiece of the deck, and the wreck runs down to 40 m (130 ft), with the seabed at 42 m.
The wreck
- Vessel
- Unkai Maru
- Type
- Steamship (former S/S Venus)
- Length
- 110 m (361 ft)
- Built
- 1902
- Cause
- Sunk by US dive bombers in Operation Hailstone
- Lies
- On the floor of Truk Lagoon at about 42 m
Unkai Maru was built in England in 1902 as the S/S Venus and was sold to the Japanese navy in 1911. US dive bombers sank her in Truk Lagoon during Operation Hailstone, the two-day strike of 17 and 18 February 1944, and she now rests on the lagoon floor at about 42 m.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Prime | Prime | Prime | Good | Good | Fair | Fair | Fair | Fair | Good | Good | Prime |
Season follows Chuuk Lagoon: December to April is the dry season, driest from January to March; June to September brings the heaviest rain.
Photos from Unkai Maru
mattk1979 · CC BY-SA 2.0
Dive videos
Unkai Maru No 6. Truk lagoon · Max Gleeson's Shipwrecks of the World on YouTube
Sources
- Commonly Visited Truk Dive Sites — Truk Odyssey
- Shipwreck Unkai Maru — TracesOfWar
- Wrecks — Truk Stop Hotel
- Unkai Maru No. 6 — Pacific Wrecks
- IJN Unkai Maru No. 6: Tabular Record of Movement — Combined Fleet
Photo credits
- Two round pressure gauges on an encrusted pipe in a wreck engine room, lit against dark blue water. by montereydiver, CC BY 2.0, via Wikimedia Commons
- Coral and sponges cover a wreck structure, with a white coral head and small blue fish. by mattk1979, CC BY-SA 2.0, via Openverse
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Soft and hard coral from a shallow mast to the stern
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Submarine periscopes still stacked in the holds
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