The Only Submarine Kill Ever Made While Both Were Submerged

Описание: The Only Submarine Kill Ever Made While Both Were Submerged

On February 9, 1945, HMS Venturer fired four unguided torpedoes at a German U-boat neither crew could see continuously.
Three missed. The fourth created the only known submarine kill in history while both boats were submerged.

Off the Norwegian coast, Lieutenant James “Jimmy” Launders and the crew of HMS Venturer had spent nearly three hours silently tracking U-864.

The German submarine was carrying out Operation Caesar — an attempt to move military technology, technical specialists, and strategic material from Germany toward Japan.

But sinking her presented a problem unlike an ordinary submarine attack.

U-864 remained submerged.
She was zig-zagging.
Her exact depth was uncertain.
Venturer avoided continuous active ASDIC tracking.
And the torpedoes Launders fired could not guide themselves toward the target after launch.

So how did four torpedoes fired 17.5 seconds apart produce a hit against a submarine moving somewhere beneath the North Sea?

This Admiralty Files documentary reconstructs the pursuit, the intelligence behind the interception, the mathematics of the firing problem, and the decision-making that allowed Venturer to turn incomplete information into one of the most unusual submarine attacks of the Second World War.

We also examine Operation Caesar, U-864’s cargo, the wreck discovered off Fedje decades later, and why the real lesson of the engagement was not a secret weapon — but disciplined observation, fire control, patience, and the management of uncertainty.

00:00 - The Only Submerged Submarine Duel in History
02:30 - Operation Caesar: U-864's Secret Cargo for Japan
05:15 - Intercepted: Why HMS Venturer Was Waiting in Norway
07:45 - The 3D Firing Problem: Tracking an Invisible Target
10:30 - Three Hours of Silence: Hydrophones and Zig-Zags
13:10 - The Four-Torpedo Spread: Mathematics Over Luck
16:00 - Impact at 12:14: Breaking the Impossible Barrier
18:20 - The Mercury Legacy: The Wreck West of Fedje
20:45 - Why Launders' Geometry Still Matters

Subscribe to Admiralty Files for military history focused on engineering, doctrine, operational records, and the systems behind battlefield results.

#wwii #submarines #royalnavy