Patrol 1

26 June 1944- 14 Aug 1944

Takamiya Maru - Small vessel not credited to Cobia in JANAC

大慈丸 Taishi Maru

第十雲海丸 Unkai Maru No. 10

日秀丸 Nisshu (Nissyu) Maru

第三郵船丸 Yusen Maru #3 - Small vessel not credited to Cobia in JANAC

Unidentified Vessel - thought to have been Kaio Maru No. 2 - not credited to Cobia in JANAC. Probable misidentification. A vessel with this name was sunk later in the war by U.S. aircraft

Shoei Maru - Small vessel not credited to Cobia in JANAC. Alden and Cressman list this vessel as damaged, not sunk.

弥生丸 Yayoi Maru - Small vessel not credited to Cobia in JANAC. This ship was also hit by US aircraft. Prisoner taken.

Patrol 2

6 Sep 1944- 5 Nov 1944

No sinkings

Patrol 3

30 Nov 1944-24 Jan 1945

由利島 Yurijima ("Yurishima" in some sources, including JANAC)

Patrol 4

18 Feb 1945-15 Apr 1945

Unidentified Sea Truck - Small vessel not credited to Cobia in JANAC.

Unidentified Sea Truck - Small vessel not credited to Cobia in JANAC.

Note: Alden (citing Muthlthaler) lists one of thess vessels as "Comm. Ship #311 Go." Both vessels were seen to sink.

Patrol 5

9 May 1945-18 Jun 1945

Unidentified Sailing Junk- Small vessel not credited to Cobia in JANAC. Alden says, "Claim Unconfirmed."

白沙 Hakusa

Unidentified Vessel mistakenly identified as "Ninshin Maru No. 22" in JANAC. ULTRA reported the ship as "Nanshin Maru No. 22." Alden (citing Muthlthaler) says Nanshin Maru No. 22 was surrendered at the end of the war, but credits Cobia with "having hit an unknown ship."

Patrol 6

18 Jul 1945-22 Aug 1945

No Sinkings

ships, tons ( were small vessel often not included in sinkings)

JANAC - 6 ships, 16,835 tons. Note that the criteria JANAC used included all Japanese Naval vessels (although JANAC did not usually count warships less than 500 tons that were converted from merchant ships) and all Japanese merchant vessels of 500 or more gross tons known or believed to have been lost during the war. Differences between JANAC figures and current research are noted above.

Alden-McDonald credit Cobia with 14 ships and 20,821 tons sunk.

SORG credits Cobia with 14 ships and 40,700 tons sunk.

USS Cobia at War credits Cobia with 14 ships and 40,646 tons sunk, but also cites Alden who credits Cobia with 14 ships and 20,821 tons sunk.

Wrecksite credits Cobia with ships and tons sunk.

Japanese Naval and Merchant Ship Losses - JANAC on the NHHC website

JANAC on the Hyperwar website - https://www.ibiblio.org/hyperwar/Japan/IJN/JANAC-Losses/JANAC-Losses-6.html

SORG- http://archive.hnsa.org/doc/subreports-sorg.htm (Excel spreadsheet download)

Archives of the Pacific Fleet Submarine Museum (PFSM)

War Patrol Reports - USS Cobia -

Monthly Losses of Combatant and Non-Combatant Vessels

太平洋戦争時の喪失船舶明細表（汽船主体）- Lost Vessel table during the Pacific War (merchant vessels)

Alden, John D., and McDonald, Craig R. - U.S. & Allied Sub Successes in the Pacific & Far East during WWII - Fourth Edition, 2009

Calenberg, Jerry - USS Cobia at War, Wisconsin Maritami Museum, 2002, revised 2019.

Cressman, Robert - The Official Chronology of the U.S. Navy in World War II, Naval Institute Press, 2000.

Wrecksite - https://www.wrecksite.eu/wrecksite.aspx

Miramar Ship Index - https://www.miramarshipindex.nz/

Imperial Japanese Navy Page - http://www.combinedfleet.com/

Wikipedia Japan - https://ja.wikipedia.org/wiki/

Japan Center for Asian Historical Records - National Archives of Japan - https://www.jacar.go.jp/index.html

Official U.S. Navy Photos - Naval History & Heritage Command

Archives of the Pacific Fleet Submarine Museum (PFSM)

Japanese Merchant Ship photos - Wrecksite - copyright owners retain all rights. Photos used on this site will be taken down should the owner request their removal.