On June 4, 1942, a damaged Zero flipped over in the marsh mud of Akutan Island in the Aleutians, killing pilot Tadayoshi Koga but leaving the aircraft largely intact. That accident handed the Allies the key to defeating the most produced Japanese combat aircraft of World War II. This episode follows the Zero from the near-impossible 1937 Imperial Navy requirements that drove Nakajima out of the competition to designer Jiro Horikoshi’s fanatical weight reduction using extra-super-duralumin, a one-piece wing and fuselage, and no armor or self-sealing fuel tanks.

The result was a fighter with a stall speed under 69 miles per hour, a 1,600-mile range, and a 12 to 1 kill ratio in the early Pacific war. But the same fragility that made it agile made it a glass cannon, and Japan could not replace the veteran pilots it lost. American test pilots flying the recovered Akutan Zero discovered its controls stiffened above 216 miles per hour and that it rolled right more slowly than left, insights that shaped the Thach Weave and boom-and-zoom tactics. Later variants like the Model 32 and Model 52 could not escape the closed design loop that made the Zero great in the first place.

• The 1937 requirements for speed, climb, cannons, carrier-size wingspan, and six to eight hours of endurance
• How low wing loading gave the Zero its legendary turning ability
• Saburo Sakai’s account of pouring hundreds of rounds into a Grumman Wildcat that kept flying
• Why Koga’s wingmen refused to strafe the crashed plane and how a U.S. salvage team recovered it
• The irony that most flyable Zeros today run on American Pratt and Whitney engines