This is a Momentous Other milestone.
Type Certificate H-1 was awarded in the USA to a Bell Model 47. The certificate was issued by the Civil Aeronautics Administration (CAA) in Washington, USA signed by Charles F. Dycer, Director, Aircraft and Components Service.
Source: "The Bell 47 Helicopter Story – Birth of the Commercial and Military Helicopter Industry", Robert S. (Bob) Petite and Jeffrey C. Evans, Helicopter Heritage Canada (ISBN: 978-1-882824-45-8), November 2013, Page 45