Naval Historywith Dr. Alex

Q&A · 5:53:28-5:59:43

HMS Venturer's submerged attack on U-864

James Launders solved a three-dimensional firing problem and achieved the only recorded submarine-versus-submarine kill with both boats submerged.

Fire ControlHMS VenturerJames LaundersSubmarine WarfareTorpedoesU-864
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Question

What is the most interesting example of a U-boat being defeated in the Second World War?

Short answer

HMS Venturer's fully submerged attack on U-864, solved by James Launders with estimated three-dimensional torpedo geometry.

Notes

After tracking U-864 for three hours, James Launders had to act before Venturer's batteries lost their charge. Without a visible target for a normal periscope solution, he estimated bearing, speed, depth, and the evasive movements the U-boat would make. Venturer fired its four bow torpedoes at different depths with 17.5-second spacing, then dived to avoid possible retaliation. U-864 evaded three torpedoes, but the fourth struck amidships and broke the boat in two. Launders received the Distinguished Service Order, and several crew members also received awards. The wreck's mercury cargo, bound for Japan, adds an environmental problem to the history of the attack.