Midget submarines offered another way to put torpedoes into American ships during the attack. Their weapons avoided the risk of an air-dropped torpedo striking the harbour bottom on entry. The air raid could help conceal the submarines' presence and cover their operations. Torpedo holes and uncontrollable fires offered different ways to sink ships, giving the combined attack more than one means of causing fatal damage.
Notable Point · 1:48:41-1:49:24
Why midget submarines accompanied the air strike
Submarine torpedoes avoided the aerial weapon's water-entry problem, while the air raid could cover the submarines' operations.