[2] Thach spent the next decade serving as a test pilot and instructor and establishing a reputation as an expert in aerial gunnery.

As the war progressed, the Japanese Navy lost their experienced pilots due to attrition and had no well-trained replacements, while the United States was able to improve the general fighting ability of their own personnel.

When the Japanese resorted to the feared Kamikaze suicide attacks, Thach developed the "big blue blanket" system to provide an adequate defense.

[1] Thach was also present at the formal Japanese surrender aboard the battleship USS Missouri on September 2, 1945, in Tokyo Bay.

In 1958 and 1959, Thach was placed in command of an antisubmarine development unit, "Task Group Alpha", with the aircraft carrier Valley Forge (CVS-45) serving as his flagship.

As Commander in Chief, United States Naval Forces Europe, starting in 1965, he pinned on his fourth star as a full admiral, retiring from the Navy in May 1967 from that position.

Thach died on April 15, 1981, in Coronado, California, four days before his 76th birthday, and was buried at Fort Rosecrans National Cemetery in San Diego.