Station HYPO

Speech on Hypo by CAPT Biard, July, 12 2002

Let me now discuss the Japanese Navy’s important strategic code system, the JN-25.

It was 10 December, just three days after the attack on Pearl, that Washington gave a very dispirited Dungeon crew permission to join in on the attack on JN-25, a system that was a stranger to almost all of us. Unfortunately, a major change had been made in it on 4 December. The complicated, lengthy, and very difficult cipher applied to the code was changed. That was bad. But, fortunately, the code-book itself, which had been in use since 1 December 1940, was not replaced. That was good. In spite of the very limited success achieved with that system we did not want to have to start again completely from scratch. Washington and Corregidor had spent much time and effort getting that start on the codebook itself.

On December 25, 1943, USS Gurnard (SS 254) snuck into Tokyo Bay where the crew took a photo of Mount Fuji through the periscope. The crew then had Christmas dinner as the Imperial Japanese Navy patrolled above them. Submariners are a different breed.

Speech on Hypo by CAPT Biard, July, 12 2002

Joe Rochefort was intuitive, quick, sharp thinking, blessed with a fantastic memory of almost total recall, and was an inspiring leader for his miracle-producing associates. He came, he saw, he understood, he encouraged, he inspired, he pointed out new approaches to problems that were stopping us and, above all, the estimates and summaries he sent to the high command were almost always highly correct and, frequently, even prophetic. He kept our team working smoothly, brilliantly, and efficiently. He was the incomparable Joseph J. Rochefort, Japanese linguist, expert traffic analyst, leader among code breakers, and intelligence specialist extra-ordinary.

Speech on Hypo by CAPT Biard

July, 12 2002

On 7 December, 1941, some 10 officers and about 30 enlisted men were serving in a highly secret operational intelligence group in the basement of the Administration Building in Pearl Harbor. This group was a fairly new unit — the newest of the U. S. Navy’s three World War II code-breaking stations. It had been placed in operation only seven months earlier — on 1 May 1941. The senior and oldest of the three stations was in Washington, D.C. [OP-20-G]. A second station was operating in the Philippines on the island of Corregidor in the entrance to Manila Bay.

ATN3 David Monroe Willis
December 22, 1946 – April 15, 1969

FORT GEORGE G. MEADE, Md.:

The Cyber National Mission Force officially became the Department of Defense’s newest subordinate unified command during a ceremony at U.S. Cyber Command Headquarters here, Dec. 19, 2022, highlighting the evolution of a persistent, professional cyber force today and into the future.