Swordfish reliability and shallow-water torpedo attacks

Eagle and Illustrious could draw on a large, repairable stock of Swordfish airframes, including stored machines and floatplanes that could be converted back to deck use. Their design emphasized easy operation at night so crews could devote attention to navigation while carrying torpedoes. A tension wire unspooled during the drop to stabilize the weapon and limit its dive after entering the water. That shallow-water control was separate from the duplex contact and magnetic fuzes that could still fail after a good entry. Five of the eleven British torpedoes hit their targets, and only two buried themselves in the harbour bottom. This controlled entry contrasts with the diving problems that reduced Japanese torpedo effectiveness at Pearl Harbor.