Additional Naval Armaments Supplement Programme
# Additional Naval Armaments Supplement Programme

The Additional Naval Armaments Supplement Programme (マル追計画, 追加計画, Maru Tsui Keikaku, Tsuika Keikaku) was one of the naval expansion plans of the Imperial Japanese Navy (IJN).

## Background

In November 1941, the IJN required many additional submarines for the Pacific War, as a pressing matter. To meet this need, the IJN negotiated with the Ministry of Finance and received approval for 32 submarines and one target ship. Later, they were concluded by 78th, 79th and 81st Imperial Diet.

## Table of vessels

| Category | Class | Vessel number(s) | Completed | Converted | Cancelled |
| - | - | - | - | - | - |
| Cruiser submarine Type-A | I-12 | #620, #621 | I-12 (#620) | #621 was converted to the I-13 class | |
| Cruiser submarine Type-A | I-13 | | I-13 (#621) | | |
| Cruiser submarine Type-B | I-54 | #627, #629, #631, #633 - 636 | I-54 (#627), I-56 (#629), I-58 (#631) | | #633 - 636 |
| Cruiser submarine Type-C | I-52 | #625, #626, #628, #630, #632 | I-52 (#625), I-53 (#626), I-55 (#628) | | #630, #632 |
| Medium-sized submarine | Ro-35 | #640 - 654 | Ro-56 (#645) | | #640 - 644, #646 - 654 |
| Tanker submarine | I-351 | #655 - 657 | I-351 (#655) | | #657 |
| Target ship | Hakachi | #660 | Hakachi (#660) | | |
