Joint Army–Navy Assessment Committee (JANAC) was a United States inter-service agency set up to analyze and assess Japanesenaval and merchant marine shipping losses caused by U.S. and Allied forces during World War II.
By agreement between Chief of Staff and Commander-in-Chief, a Committee composed of 4 Navy and 3 Army members is appointed to meet from time to time at the call of the senior member to study and evaluate reports of loss or damage of enemy Naval and Merchant vessels from all causes, except those cases considered by the Anti-Submarine Warfare Assessment Committee of the Office of the Commander-in-Chief, U.S. Fleet. Findings of the Anti-Submarine Warfare Assessment Committee will be included in the overall evaluation of enemy losses without further review. Periodic reports of the Committee will be submitted jointly to the Chief of Staff and Commander-in-Chief.[1]
The assessment of losses, unanimously agreed to by all JANAC members of the committee, was published in 1947, which included:
All Naval vessels known or believed to have been lost.
All merchant vessels of 500 or more gross tons known or believed to have been lost.
JANAC provided a detailed chronology of Japanese naval and merchant marine losses cross-indexed in the appendix of its final report, including a separate summary about losses caused by U.S. submarines.[1] JANAC noted that a negligible number of vessels were not assessed because of insufficient information as to the cause of loss.[3]
Sinking Agent
Naval Vessels
Merchant Vessels
Total Vessels
No.
Tonnage
No.
Tonnage
No.
Tonnage
TOTALS:
686
1,965,646
2,346
8,618,109
3,032
10,583,755
United States (U.S.):
611
1,822,210
2,117
7,913,858
2,728
9,736,068
Submarines
201
540,192
1,113
4,779,902
1,314
5,320,094
Surface Warships
112
277,817
11
43,349
123
321,166
Army Aircraft
70
62,165
240
639,667
310
701,832
Carrier Aircraft
161
711,236
359
1,390,241
520
2,101,477
Land-based Navy-Marine Aircraft
11
13,402
88
218,718
99
232,120
Army-Navy-Marine Aircraft
9
48,750
23
114,306
32
163,056
Navy Shore Batteries
2
2,770
—
—
2
2,770
Mines
19
17,995
247
591,660
266
609,655
Aircraft and Other Agents
26
147,883
32
132,710
58
280,593
Unknown Agents
—
—
4
3,305
4
3,305
Allied Forces:
45
69,636
73
211,664
118
281,300
United Kingdom (U.K.)
28
50,365
42
87,981
70
138,346
Netherlands
7
8,099
15
57,471
22
65,570
Australia
5
6,892
8
24,910
13
31,802
China
—
—
3
14,327
3
14,327
Soviet Union
2
1,660
2
8,233
4
9,893
New Zealand
2
2,095
—
—
2
2,095
Netherlands and Australia
—
—
2
8,303
2
8,303
Netherlands and India
—
—
1
10,439
1
10,439
Australia and India
1
525
—
—
1
525
U.S. and Allied Forces:
10
14,864
12
57,923
22
72,787
U.S. and Australia
4
7,550
7
37,072
11
44,622
U.S., Australia, and Netherlands
—
—
2
16,362
2
16,362
U.S. and U.K.
5
5,102
2
3,500
7
8,602
U.S. and New Zealand
1
2,212
—
—
1
2,212
U.S., U.K., and Netherlands
—
—
1
989
1
989
Marine Casualties:
13
50,338
97
268,948
110
319,286
Pacific Theater of Operation (PTO)
Japanese Naval and Merchant Shipping Losses by the Allied forces
Japanese Naval and Merchant Shipping Losses by U.S. forces
PTO naval campaign
Legacy
Submarine service
JANAC significantly altered wartime estimates for Japanese losses inflicted by the U.S. Navy's submarine service. At the end of World War II, Vice AdmiralCharles A. Lockwood and his COMSUBPAC staff had estimated that approximately 4,000 ships had been sunk, totalling 10 million tons lost. JANAC revised this total to 1,314 enemy vessels and 5.3 million tons sunk.[4] JANAC estimates of Japanese losses revised wartime claims downward for most war patrols carried out by the submarine service during World War II as noted in the following table of the revised list of top ten submarines based upon the total tonnage sunk as determined by JANAC.[5]
Although JANAC tended to revise downward wartime estimates, one noteworthy exception involved the fifth war patrol of Archerfish (SS-311) under the command of CommanderJoseph F. Enright. Archerfish was credited with sinking a 24,000-ton Hiyō-class aircraft carrier during the war, but JANAC determined he had actually sunk the 66,000-ton carrier Shinano, making this the most successful submarine patrol of the Pacific War.[10]
^Key Jr, David M. (September 2001). Admiral Jerauld Wright: Warrior among Diplomats. Manhattan, Kansas: Sunflower University Press. ISBN1-55750-217-X., pp. 236–240
^Blair Jr., Clay (2001). Silent Victory: The U.S. Submarine War Against Japan. Philadelphia: Lippincott. pp. 876–878. ISBN1-55750-217-X.; hereafter referred to as Silent Victory
^Data compiled from Silent Victory, Appendices E, F, J & K
^Blair and Roscoe agree at 100,231 tons. Neither included 1/2 credit for Tosan Maru at 8,666 tons shared with Crevalle
^Blair and Roscoe agree at 96,628 tons. Neither included 1/3 credit for Hikoshima Maru at 2,854 tons shared with Picuda and Queenfish
^Blair and Roscoe agree at 88,091 tons. Neither included 1/3 credit for Takane Maru at 10,021 tons shared with Salmon and Sterlet
