“AF is having problems with is fresh water condenser.” AF was Midway and the US Navy now knew the target of Operation K. All of this happened because the Japanese code, known as JN-25, was being broken by Naval cryptanalyst lead by Commander Joseph John Rochefort.

The target know as AF was actually unknown to Navy until a simple plain language, uncoded, message was sent from Midway to Hawaii claiming its fresh water condenser was broken. The Japanese relayed this information back to their headquarters. The American’s intercepted their message and knew of the target. They knew the time and location of the attack and were able to plan their own counter attacks based on this information.

Knowledge is power and it proved to be the edge the struggling US Navy needed.