Naval Historywith Dr. Alex

Q&A · 1:30:12-1:30:41

How Allied intelligence misread Yamato

Allied estimates of the Yamato class were substantially wrong, with British assessments somewhat closer than American ones but still underestimating the main guns.

BattleshipsImperial Japanese NavyNaval IntelligenceYamato Class Battleships
Watch at this timeFull video guide
Question

Did the United States or Britain know Yamato's true characteristics while the class was being built?

Short answer

No; American estimates were badly wrong, and British estimates were only somewhat closer, at roughly 17-inch guns.

Notes

Intelligence organizations were watching Japan, yet they did not know the Yamato class's true characteristics. Surviving American estimates were far off the mark. British estimates came closer only by placing the guns around 17 inches instead of identifying the actual 18-inch battery. Any counterfactual response to Yamato must therefore account for the imperfect information available to Allied planners.