Pacific field commanders had tried field modified mechanized flame throwers early on, with the Marine Corps deciding to leave further development to the Army. The Navy had an interest in flame throwing and five Navy Mark I flamethrowers arrived in Hawaii in April 1944. The Navy deemed them "unsuitable" due to their weight and turned the over to the Army's Chemical Warfare Service. In May a top secret composite unit was assembled at Schofield Barracks. It was led by Colonel Unmacht of the US Army Chemical Warfare Service, Central Pacific Area (CENPAC) Col. Unmacht began the project with only the 43rd Chemical Laboratory Company. They modified the first light tank designating it a "Satan". The flame tank group was expanded with men from the 5th Marine tank battalion and 25 from the 117th CB. The newly attached Seabees went over what the Army had created and concluded it was a little over engineered. They recommended reducing the number of moving parts from over a hundred to a half dozen.