IJN Submarine RO-32
Date of Action: 9 July 1942
USCG Units Involved: USS McLane, CG; USS YP-251
Location: 55.20N x 134.40W
Credit by U.S. Navy? Yes; the Joint Army-Navy Assessment Committee gave credit to the McLane, YP-251 and a Royal Canadian Air Force aircraft
Enemy warship's commanding officer: Unknown
Enemy casualties: Unknown
U.S.C.G. casualties: None
Misc: See below
On 9 July 1942 the U.S.S. McLane, C.G. and U.S.S. YP-251 reported attacking a submarine off the coast of Ketchikan, Alaska, after receiving a message from a Royal Canadian Air Force patrol aircraft that it had attacked and damaged a submarine. Upon reaching the area, the McLane picked up a sound contact on sonarq. During this incident the commanding officer of the McLane as well as many of the crew saw an air-driven torpedo pass underneath his cutter's bow. Both vessels retraced the track of the torpedo and lookouts saw a periscope that quickly submerged. The depth charge attacks continued in the area and some of the crewman reported hearing and feeling a large secondary explosion. The crewmen reported seeing large air bubbles as well as diesel oil come to the surface for a number of hours.
The Coast Guard District Officer gave the McLane, YP-251 and the RCAF aircraft credit for sinking a submarine in the area. The Joint Army-Navy Assessment Committee in their report Japanese Naval and Merchant Shipping Losses During World War II By All Causes (Washington, DC: US Government Printing Office, February 1947, p. 3) also credited Allied "Surface Craft" and "Aircraft" with the sinking. However, in 1967 the U.S. Navy, citing two sources that were "more accurate" noted that the RO-32 was stricken from the Japanese Navy list on 1 April 1942 and was still afloat at the end of the war. Therefore in a letter to the Commandant from the Chief of Naval Operations (13 DEC 1967, OP-09B92/crp Ser 6647P09B9) "this office feels that McLANE's claim cannot be confirmed." To add to the confusion Captain Mochitsura Hashimoto, IJN, in his Sunk: The Story of the Japanese Submarine Fleet, 1941-1945 (published in 1954 and using Japanese documentation) does credit a "U.S.C.G. cutter, district craft and R.C.A.F. aircraft" with sinking the RO-32 off the coast of Alaska (p. 262).
Until a wreck is found near the area of the original attacks this claim remains officially unconfirmed.