Wartime Naval Armaments Supplement Programme

The Wartime Naval Armaments Supplement Programme (マル戦計画, 昭和十八年度戦時艦艇建造計画, Maru Sen Keikaku, Shōwa-Jūhachi-Nendo Senji Kantei-Kenzō Keikaku) was the 1943-44 War Programme to fund the armaments expansion plan of the Imperial Japanese Navy (IJN).

Background

Early 1944, the IJN started building warships for war. The plan did not include any large warships which were suitable for offensive operations.

Table of vessels funded under 1944-45 Estimates

Category	Class	Vessel number(s)	Completed	Converted	Cancelled
Military transporter 2nd class	No.101	#1501–1569 and 32 vessels	No.101 and 68 vessels	22 vessels were transferred to the Army.	32 vessels
Coast defence boat Type-A (steel)	No.1	#1701–1760
Minelayer	Kamishima	#1801–1809	Kamishima (#1801), Awashima (#1802)		#1803–1809
	Minoo	#1821–1822	Minoo (#1821)		#1822
Coast defence boat Type-B (wooden)	No.101	#1851–1870
Auxiliary subchaser	Aux. No.1	#2001–2100	Aux. No.151 (#2001) to Aux. No.250 (#2100)
Auxiliary patrol boat	Aux. No.1	#2121–2400	Aux. No.1 (#2121) and 26 vessels		#2125–2144, 2148–2150, 2155–2156, 2159–2173, 2176–2183, 2187–2203, 2207–2209, 2214–2229, 2232–2241, 2244–2252, 2261–2271, 2277–2282, 2287–2292, 2302–2310 and 2314–2400
Escort ship Type-C	No.1	#2401--2532	No.1 (#2401) and 55 vessels		#2446--2447, 2450--2452, 2455--2502, 2505--2506, 2515--2532 and 168 vessels
Escort ship Type-D	No.2	#2701--2843	No.2 (#2701) and 66 vessels		#2735, 2740, 2743--2750, 2754--2755, 2757, 2760--2761, 2764, 2768, 2770, 2773--2774, 2776, 2781--2792, 2794, 2803--2843 and 57 vessels
Military transporter 1st class	No.1	#2901--2922 and 12 vessels	No.1 (#2901) and 20 vessels		12 vessels
Submarine Type-D	I-361	#2961	I-372 (#2961)
	I-373	#2962--2967	I-373 (#2962)		#2963--2967
	S60	#2968--2971			#2968--2971
Submarine Type-E	S54-2	#2981--3024 and 48 boats			#2981--3024 and 48 boats
Patrol torpedo boat	PT-151, PT-201, PT-220, PT-235, PT-241, PT-301, PT-327, PT-411, PT-468, PT-469, PT-474, PT-491, PT-538, H-2, H-10, H-27, H-74 and H-101	1540 vessels	approx. 860 vessels		unknown
High-speed submarine (large)	I-201	#4501--4506	I-201 (#4501), I-202 (#4502), I-203 (#4503)
	S56B	#4507--4523			#4509--4523
Transport submarine (small)	Ha-101	#4601--4612	Ha-101 (#4601), Ha-102 (#4602), Ha-103 (#4603), Ha-104 (#4604), Ha-105 (#4605), Ha-106 (#4606), Ha-107 (#4607), Ha-108 (#4608), Ha-109 (#4609), Ha-111 (#4611)		#4610 and #4612
Escort ship Type-B	Ukuru	#4701–4721	Inagi (#4701), Habushi (#4702), Ojika (#4703), Kanawa (#4704), Uku (#4705), Takane (#4707), Kuga (#4709), Shiga (#4711), Iō (#4712)		#4706, #4708, #4710 and #4713–#4721
Destroyer Type-D	Matsu	#4801 - 4832	Nire (#4809), Nashi (#4810), Sii (#4811), Enoki (#4812), Odake (#4814), Hatsuume (#4815)		#4801–4808, 4813 and 4816–4832
Fleet oiler	Hario	#4901–4904	Hario (#4901)		#4902–4904
High-speed submarine (small)	Ha-201	#4911–4989	Ha-201 (#4911), Ha-202 (#4912), Ha-203 (#4913), Ha-204 (#4914), Ha-205 (#4915), Ha-207 (#4917), Ha-208 (#4918), Ha-209 (#4919), Ha-210 (#4920), Ha-216 (#4926)		#4916, #4921 - #4925, #4927 - #4989 (of which 11 were launched and 16 more laid down; 42 cancelled before laying down{

Table of vessels funded under 1945-46 Estimates

This programme was projected only, and the vessels were never ordered.

Category	Class	Quantity planned
High-speed submarine (large)	I-201	76 vessels
Submarine Type-D	I-373	140 vessels
Transport submarine (small)	Ha-101	88 vessels
High-speed submarine (small)	Ha-201	10 vessels
Escort ship Type-C	No.1	168 vessels
Escort ship Type-D	No.2	60 vessels

References

• Rekishi Gunzō series, Gakken (Japan)
• The Maru Special series, Ushio Shobō
• Daiji Katagiri, Ship Name Chronicles of the Imperial Japanese Navy Combined Fleet, Kōjinsha (Japan), June 1988, ISBN 4-7698-0386-9
• "The Society of Naval Architects of Japan". (SNAJ), Histories of shipbuilding in Shōwa period (1), "Hara Shobō". (Japan), September 1977
• 大日本帝国海軍艦艇一覧 (ja)

See also

• 1st Naval Armaments Supplement Programme (Maru 1 Keikaku, 1931)
• 2nd Naval Armaments Supplement Programme (Maru 2 Keikaku, 1934)
• 3rd Naval Armaments Supplement Programme (Maru 3 Keikaku, 1937)
• 4th Naval Armaments Supplement Programme (Maru 4 Keikaku, 1939)
• Temporal Naval Armaments Supplement Programme (Maru Rin Keikaku, 1940)
• Rapidly Naval Armaments Supplement Programme (Maru Kyū Keikaku, 1941)
• Additional Naval Armaments Supplement Programme (Maru Tui Keikaku, 1941)
• 5th Naval Armaments Supplement Programme (Maru 5 Keikaku, 1941)
• 6th Naval Armaments Supplement Programme (Maru 6 Keikaku, 1942)
• Modified 5th Naval Armaments Supplement Programme (Kai-Maru 5 Keikaku, 1942)