Ordnancemen load a bomb onto an SBD Dauntless of the VS-6 on board the carrier USS Enterprise invasions of Guadalcanal and Tulagi on August 7, 1942
In the years leading up to World War II, the United States Navy played a significant role in the development of air-launched ordnance, including torpedoes and depth charges. However, between World War I and World War II, the Navy’s progress in developing anti-shipping weapons slowed, partly due to arms limitation agreements and a climate of pacifism. This delay in innovation led to shortcomings in naval ordnance design at the beginning of the war, especially when compared to other naval powers.
Pre-War Ordnance Development Challenges
Before the start of World War II, interservice rivalries between the U.S. Army and Navy further complicated ordnance development. Both branches created their own separate sets of bombs, which were incompatible with each other. This duplication of effort was inefficient, and the lack of standardized bombs became a logistical issue.
Introduction of the A/N Standard Bomb
To address this problem, a joint service standard bomb was introduced in the late 1930s, known as the A/N bomb, which could be used by both the Army and the Navy. This shared design simplified production and distribution, although there were still differences in the fusing mechanisms to accommodate the operational needs of each branch. For instance, the Army’s bombs were typically armed immediately upon release from the bomb rack, while the Navy’s bombs had a timed delay fuse, which was essential for carrier-based operations. This delay allowed for safer handling of bombs on deck, reducing the risk of premature explosions.
Specialized Navy Armor-Piercing Bombs
In addition to the standard A/N bombs, the Navy developed specialized armor-piercing bombs, often in the 1,000 lb range, equipped with delayed-action fuses. These bombs were designed to penetrate the heavy armor of enemy ships before detonating. The success of these bombs became evident during pivotal battles, such as the Battle of Midway, where U.S. Navy SBD-2 and SBD-3 Dauntless dive-bombers from VB-6 used these armor-piercing bombs to devastating effect. Two bombs from Dauntless dive-bombers struck the Japanese aircraft carrier Akagi, penetrating its flight deck and causing catastrophic explosions that eventually led to its sinking.
Impact on Naval Aviation
The development and successful deployment of specialized bombs like these greatly enhanced the effectiveness of U.S. Navy aviation in the Pacific Theater. The ability to deliver precision strikes against heavily armored targets from the air marked a significant advancement in naval warfare tactics. The use of dive-bombers equipped with these armor-piercing bombs became a key element in the Navy’s success against Japanese carriers and surface ships, contributing to decisive victories in major battles such as Midway.