Japanese submarine Ro-33
 Ro-33 on 8 April 1939.
| |
| History | |
|---|---|
 Japan | |
| Name | Original name unknown |
| Builder | Kure Naval Arsenal, Kure, Japan |
| Laid down | 8 August 1933 |
| Launched | 10 October 1934 |
| Renamed | Ro-33 on 10 October 1934 |
| Completed | 7 October 1935 |
| Commissioned | 7 October 1935 |
| Decommissioned | 15 November 1939 |
| Recommissioned | 1 May 1940 |
| Decommissioned | 15 May 1941 |
| Recommissioned | ca. mid-November 1941 |
| Fate | Sunk 29 August 1942 |
| Stricken | 5 October 1942 |
| General characteristics | |
| Class and type | Kaichū type submarine (K6 subclass) |
| Displacement |
|
| Length | 73 m (239 ft 6 in) overall |
| Beam | 6.7 m (22 ft 0 in) |
| Draft | 3.25 m (10 ft 8 in) |
| Installed power |
|
| Propulsion |
|
| Speed |
|
| Range |
|
| Test depth | 75 m (246 ft) |
| Crew | 75 |
| Armament |
|
Ro-33 was an
Design and description
The submarines of the K5 sub-class were versions of the preceding KT sub-class with greater surface speed.[1] They displaced 955 tonnes (940 long tons) surfaced and 1,219 tonnes (1,200 long tons) submerged. The submarines were 73 meters (239 ft 6 in) long, had a beam of 6.7 meters (22 ft 0 in) and a draft of 3.25 meters (10 ft 8 in). They had a diving depth of 75 meters (246 ft).[2]
For surface running, the boats were powered by two 1,450-
The boats were armed with four internal bow 53.3 cm (21.0 in)
Construction and commissioning
Ro-33 was
Service history
Pre-World War II
Upon commissioning, Ro-33 was attached to the
Ro-33 returned to active service on 1 May 1940, with Submarine Division 21 reassigned to Submarine Squadron 5 in the 4th Fleet.[5] She departed Sasebo on 16 May 1940 for a lengthy training cruise in the Caroline Islands, Marshall Islands, and Mariana Islands which concluded with her arrival at Yokosuka, Japan, on 22 September 1940.[5] She participated in a naval review at Yokohama, Japan, on 11 October 1940.[5] Submarine Division 21 was reassigned to Submarine Squadron 4 on 15 November 1940.[4][5]
Ro-33 and her sister ship Ro-34 were placed in Third Reserve at Sasebo, Japan, on 15 May 1941,[4] and while in reserve Ro-33 relieved Ro-34 as flagship of Submarine Division 21 on 21 May 1941.[4] From mid-October through early November 1941 she underwent repairs and a refit at Maizuru Naval Arsenal in Maizuru, Japan.[4] After the work was complete, she returned to active service, probably in mid-November 1941.[5]
World War II
The
First war patrol
On 21 December 1941, Ro-33 got underway from Cam Ranh Bay to begin her first war patrol, assigned an operating area in the
Second war patrol
On 13 January 1942, Ro-33 departed Cam Ranh Bay for her second war patrol, bound for a patrol area in the South China Sea southeast of
Third war patrol
Ro-33 began her third war patrol on 8 February 1942, putting to sea from Cam Ranh Bay and again ordered to patrol off Anambas, in the same area as the submarine I-53.[4] Attached to the A Unit along with Ro-34 on 9 February 1942, she arrived in her patrol area on 10 February 1942.[4]
On 13 February 1942, Ro-33 moved to a new patrol area in the
March–April 1942
On 10 March 1942, Submarine Squadron 4 was disbanded, and Submarine Division 21 — Ro-33 and Ro-34 — was reassigned to Submarine Squadron 6 in the 4th Fleet.[4] The two submarines departed Staring Bay on 22 March 1942, called at Palau from 26 to 30 March 1942, and then headed for Truk, which they reached on 3 April 1942.[4] On 4 April 1942, Submarine Division 21 was reassigned to the South Seas Force.[4] Submarine Squadron 4 was disbanded on 10 April 1942, and that day Submarine Division 21 was reassigned to Submarine Squadron 7 in the 4th Fleet.[4] The two submarines departed Truk on 15 April 1942, and on 18 April 1942 they arrived at Rabaul on New Britain.[4]
Third war patrol
Ro-33 departed Rabaul on 20 April 1942 to begin her third war patrol, with orders to conduct a reconnaissance of Port Moresby on the southeast coast of New Guinea.[4] She returned to Rabaul on 23 April 1942.[4]
Operation Mo
On 1 May 1942, Ro-33 and Ro-34 departed Rabaul bound for Port Moresby to support Operation Mo, a planned Japanese invasion of Tulagi in the Solomon Islands and Port Moresby.[4] While they were en route, the Battle of the Coral Sea began on 4 May 1942 as Allied forces moved to block the Japanese offensive.[4] As the battle continued, the two submarines arrived off Port Moresby on 5 May 1942.[4] The Japanese seized Tulagi and were turned back from Port Moresby, and Ro-33 departed her patrol area on 10 May 1942 to return to Rabaul.[4]
May–July 1942
Ro-33 and Ro-34 later moved to Truk, and on 23 May 1942 they departed Truk bound for Sasebo, where they arrived on 30 May 1944.[4] Ro-33 underwent repairs and an overhaul at Sasebo, and after the work was completed, she and Ro-34 left Sasebo on 9 July 1942, called at Truk from 17 to 23 July 1942, and proceeded to Rabaul, arriving there on 27 July 1942.[4]
Fourth war patrol
On 29 July 1942, Ro-33 began her fourth war patrol, putting to sea from Rabaul to head for a patrol area in the
On the day Ro-33 sank Mamutu, the
Ro-33 arrived off Lungga Point on 11 August 1942.
Fifth war patrol
Ro-33 put to sea from Rabaul on 22 August 1942 to begin her fifth war patrol, assigned a patrol area off Port Moresby in support of Japanese forces fighting in the New Guinea campaign.[4] By 25 August she was off southeastern New Guinea south of Samarai,[4] and she transmitted a routine status report on 26 August 1942 announcing her arrival in her patrol area.[4] The Japanese never heard from her again.[4]
Loss
To avoid attack by Japanese aircraft, the 3,310-gross register ton
Meanwhile, Arunta gained sonar contact on Ro-33 10 nautical miles (19 km; 12 mi) southeast of Port Moresby.[4] Arunta made four depth-charge attacks beginning at 13:05, and after the fourth attack her crew observed a large oil slick on the surface, marking the sinking of Ro-33 with the loss of all hands at 09°36′S 147°06′E / 9.600°S 147.100°E.[4]
On 1 September 1942, the Imperial Japanese Navy declared Ro-33 to be presumed lost off Port Moresby with her entire crew of 70.[4] The Japanese struck her from the Navy list on 5 October 1942.[4]
Notes
- ^ a b c Carpenter & Dorr, p. 122
- ^ Bagnasco, p. 187
- ^ Chesneau, p. 203
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be Hackett, Bob; Kingsepp, Sander (2016). "IJN Submarine RO-33: Tabular Record of Movement". combinedfleet.com. Retrieved 6 October 2020.
- ^ a b c d e f g h i j k l m n o Ro-33 ijnsubsite.info 25 March 2016 Accessed 6 October 2020
- ^ D Jenkins: Battle Surface- Japan's Submarine War Against Australia 1942-1944 (1992)
References
- Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
- Carpenter, Dorr B. & Polmar, Norman (1986). Submarines of the Imperial Japanese Navy 1904–1945. London: Conway Maritime Press. ISBN 0-85177-396-6.
- Chesneau, Roger, ed. (1980). Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7.
- Hackett, Bob; Kingsepp, Sander (2016). "IJN Submarine RO-33: Tabular Record of Movement". SENSUIKAN! Stories and Battle Histories of the IJN's Submarines. Combinedfleet.com. Retrieved 6 October 2020.
- Hackett, Bob; Sander Kingsepp (2003). "Kaichu Type". Sensuikan!. Combinedfleet.com. Retrieved 10 May 2009.
- Hashimoto, Mochitsura (1954). Sunk: The Story of the Japanese Submarine Fleet 1942 – 1945. Colegrave, E.H.M. (translator). London: Cassell and Company. ASIN B000QSM3L0.
