On December 7, 1941, Japanese torpedoes and bombs devastated Hawaii’s warships and air fields. The “Weapons Wall” at Pacific Aviation Museum has full-size models of three of these weapons—the ones used in the first wave of the attack. The wall also shows the aircraft that carried different types of ordnance during the first wave.
This article goes beyond the information shown on the Weapons Wall, to look at the bombs used in the second wave. The Japanese Kates and Vals of the second wave delivered different types of bombs than they delivered in the first wave—including two types of bombs not used in the first wave. Table 1 summarizes basic data about the torpedoes and four types of bombs used during the attack, and about the aircraft that delivered each weapon during the two waves.
Table 1: Japanese Bombs and Torpedoes at Pearl Harbor
| Weapon | Weight | First Wave | Second Wave | |
| Type 91 Model 2 torpedo | 838 kg 205 kg warhead |
1,847 lb 452 lb warhead |
B5N2 Kates | |
| Type 99 Model 5 ordinary (anti-ship) bomb | 800 kg | 1,763 lb | B5N2 Kates | |
| Type 98 land bomb | 250 kg | 551 lb | D3A1 Val | B5N2 Kates |
| Type 97 land bomb | 60 kg | 132 lb | B5N2 Kates | |
| Type 99 Model 1 ordinary (anti-ship) bomb: | 250 kg | 551 lb | D3A1 Val | |
Note: In Imperial Japanese Navy terminology, land bombs were general-purpose bombs used to attack land targets, while ordinary bombs were anti-ship bombs.
Two Waves
It is important to understand that the Japanese had two different types of targets during the attack. Most obviously, their main targets were battleships, carriers, and cruisers in Pearl Harbor. However, they also attacked air fields throughout Oahu to destroy the fighters at Wheeler Air Force Base and Bellows AFB and to destroy the bombers and patrol bombers at Hickam AFB, Naval Air Station Kaneohe and NAS Pearl Harbor. Fighters could intercept the attackers, and big planes could find and destroy the Japanese carriers. Continue reading
