W-19-class minesweeper

The No.19 class minesweeper (第十九号型掃海艇,) was a class of minesweepers of the Imperial Japanese Navy (IJN), serving during World War II. 70 vessels were planned under the Maru 4 Programme (Ship # 164–169), Maru Kyū Programme (Ship # 410–437) and Kai-Maru 5 Programme (Ship # 5301–5336), however, only 17 vessels were completed.

Background

 * Project number I4B. Improved model of the No.7-class. The IJN gave them a turret of 55 degrees gun elevation, because the IJN wanted to attack the strong point of behind the hill to them. And it was not useful in the Pacific War very much.
 * And after the Maru Kyū Programme vessels abolished double-curvature bow for a mass production and changed bow shape.