Several U.S. ships were involved, including the "baby" aircraft carrier USS Guadalcanal and its airmen. Captain Daniel V. Gallery, commander of the Guadalcanal, had an important objective in mind: He wanted to capture a U-boat with its encoding equipment intact.

U-505 was returning to base following an 80-day spree of destruction in the Gulf of Guinea when the USS Chatelaine radioed the Guadalcanal:

Frenchy to Bluejay - I have a possible sound contact.

Immediately responding, Guadalcanal launched her planes. One of the pilots radioed:

Sighted sub - destroyers head from spot where we are shooting.

Firing "hedgehogs," a type of depth charge, the destroyers launched the attack against 505. She was badly damaged and forced to surface.