Patrol 1

5 Jan 1942 - 7 Mar 1942

No sinkings

Patrol 2

27 Mar 1942 - 16 May 1942

Patrol 3

14 Jul 1942 - 26 Aug 1942

Patrol 4

19 Oct 1942 - 13 Dec 1942

仙台丸 Sendai Maru (listed as "UNKNOWN MARU" in JANAC

Patrol 5

7 Jan 1943 - 24 Feb 1943

潮丸 Ushio Maru

Unidentified vessel sunk by torpedo; estimated 100 men in the water after sinking; photos taken

Patrol 6

18 Mar1943 - 25 Apr 1943

上海丸 Shanghai Maru

Hissho Maru - small vessel not credited to Grayling in JANAC

Unidentified Schooner sunk by gunfire - small vessel not credited to Grayling in JANAC

Patrol 7

18 May 1943 - 6 Jul 1943

Patrol 8

30 Jul 1943 - Sep 1943 (lost)

Unidentified vessel sunk by gunfire

明山丸 Meizan Maru

USS Grayling (SS-209) was lost on this patrol.

Current research credits Grayling with sinking 6 ships, totaling 17,422 tons, including Sendai Maru (listed as "UNKNOWN MARU of 4,000 tons in JANAC) and Hissho Maru, a small vessel not credited to Grayling in JANAC, plus 3 unidentified vessels of unknown tonnage. These figures are the same for Alden-McDonald.

JANAC credits Grayling with 5 ships sunk totalling 20,575 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.known tonnage.

SORG credits Grayling with 16 ships of 61,400 tons sunk, including 2 schooners and 1 sampan with no tonnage listed..

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)

SORG on combinedfleet.com

Archives of the Pacific Fleet Submarine Museum (PFSM)

War Patrol Reports - USS Grayling

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

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//グレイリング_(SS-209)

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)

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

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.