W-1 Class Minesweepers

The W-1 class of four units were the first of the IJN's purpose-built minesweepers completed. The W-1's suffered from a top-heavy design. After torpedo boat TOMOZURU capsized in a storm in 1934, the IJN took a number of similar vessels in hand, including the W-1s, to add more ballast to improve their sea-worthiness. One 3-inch (80-mm) gun was removed to reduce top weight. In 1938, all other W-1s were so refitted. In 1944, all units of the class had their minesweeping gear removed and were rearmed with five Type 96 25-mm AA guns and armed with 36 DCs.

Builders and
Year Completed:		 Uraga Dock Co., Tokyo
1922-1925
Displacement: 615-tons standard.
Dimensions: 250' x 26.4' x 7.5'
Propulsion: 2 sets VTE, 3 Kampon boilers, 2-shafts, 4000 i.h.p, speed 20 knots
Armament: 2 x 4.7-inch 120-mm)/45 cal HA, 1-3-inch (80-mm/40-cal AA, 2 depth charge throwers