Home Intro People Events Equipment Places Maps Books Photos Videos Other Reference FAQ About

World War II Database

Type B-class Midget Submarine

Displacement47 tons full
Length78 feet
Beam6 feet
Draft10 feet
MachineryBattery/electric?, 40hp diesel, two counter-rotating screws
Speed6 knots
Range500nm at 6 knots surfaced, 84nm at 6 knots submerged
Armament2x457mm muzzle-loaded torpedoes


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

ww2dbaseJust one Ko-hyoteki Otsu Gata Type B midget submarine prototype was built in 1942 to test improvements to the Type A. Some sources suggest that a few Type A's were retrofitted into Type B's, but sources conflict.

ww2dbaseSOurces: Sources: Wikipedia; Naval History & Heritage Command; Combined Fleet.

Last Major Revision: Feb 2009

Did you enjoy this article or find this article helpful? If so, please consider supporting us on Patreon. Even $1 per month will go a long way! Thank you.

Share this article with your friends:


Stay updated with WW2DB:

 RSS Feeds

Posting Your Comments on this Topic

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 Your email will not be published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



1. We hope that visitor conversations at WW2DB will be constructive and thought-provoking. 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. All comment submissions will become the property of WW2DB.

2. For inquiries about military records for members of the World War II armed forces, please see our FAQ.

Change View
Desktop View

Search WW2DB & Partner Sites

Famous WW2 Quote
"Since peace is now beyond hope, we can but fight to the end."

Chiang Kaishek, 31 Jul 1937

Support Us

Please consider supporting us on Patreon. Even $1 a month will go a long way. Thank you!

Or, please support us by purchasing some WW2DB merchandise at TeeSpring, Thank you!