World War II Database

This article refers to the entire Type D-class; it is not about an individual vessel.

In mid-1944, with coastal defense requirements becoming urgent, the Japanese Navy developed the Koryu Tei Gata Type D midget submarines. More than just another improved version of the Type A, this was a new design. They were the largest of Japan's midgets, displacing about 60 tons, 86 feet in length, with a five-man crew, featuring a more powerful diesel engine, and had improved operating endurance. Koryu's had the same armament as the Ko-hyoteki Type A's: two muzzle-loaded 17.7-inch torpedoes. As with the earlier types, individual boats had alpha-numeric names in the "Ha" series beginning with Ha-101. Some 115 units had been completed when Japan capitulated in August 1945. Nearly 500 more were under construction. Some of these submarines intended for training pilots for Kaiten type manned torpedoes, had an enlarged conning tower and two periscopes.

Type D boats were employed off Guadalcanal and the Solomon Islands in 1942-43, where they achieved modest success against U.S. shipping. They were deployed around Midway, the Aleutians, the Bismarck Islands, the Philippines, the Marianas, and Okinawa as shore-based defensive units, but their overall effectiveness was negligible at best.

Photographs

Share this article with your friends:

Delicious   Digg   Facebook

Reddit   StumbleUpon   Twitter

Stay updated with WW2DB:

Subscribe to RSS Feeds

Advertise on ww2db.com

Posting Your Comments on this Topic

Your Name
Your Email
	Your email will not be published
Your Comments
Security Code

Note: Please refrain from using strong language. HTML tags are not allowed. Your IP address will be tracked even if you remain anonymous. WW2DB site administrators reserve the right to moderate, censor, and/or remove any comment.