To this day, there has only been one recorded instance of submarine-on-submarine warfare during WWII. The German Navy's destroyed U-864 is toxic to this day.

Here’s What You Need to Remember: World War II-era submarines needed to surface frequently to run their air-breathing diesel engines. ASV radars—even with their short effective range of six to ten ...

Here’s What You Need To Remember: Allied pilots were at first taken aback by the new aggressive tactics—but quickly adapted. If a U-Boat chose to remain surfaced and spit out flak, flyers would circle ...