The On the Roof Gang (OTRG) was a group of United States Naval Cryptologists and radiomen during World War II who are seen as the beginning of US Navy cryptology and cryptanalysis. 176 Sailors (150) and Marines (26) worked on the roof of the Navy Department building in Washington, D.C. from 1928-1941.
The "On the Roof Gang" was a school for radio-men and cryptologists who would go on to deploy on ships and at overseas bases and monitor foreign communications to monitor the movements, operations and intercept the message traffic of foreign navies.
In 1928 the Chief of Naval Operations understood that a group of formally trained operators was needed in the Pacific Fleet to monitor Japanese naval communications. There existed a small cadre of self-taught operators in the Pacific theater, and two of them were selected to become instructors in the "On-the-Roof-Gang". Chief Radioman Harry Kidder and Chief Radioman Dorman Chauncey instructed the early classes.
Initial graduates were sent to ground stations in the Pacific to monitor the Japanese. Later the cryptologists eventually began to serve on board ships.
Modern Impact
Network Warfare Command (NETWARCOM) honors Navy and Marine Cryptologists with the "On the Roof Gang" Award. The award recognizes lifetime accomplishments in the field of cryptography.
Part of the area formerly occupied by the Naval Building is now home to the Vietnam Memorial.