sentences:  The J60 conception and project design began in July 1957 at United Aircraft of Canada (now Pratt & Whitney Canada) in Montreal.The project design details were transferred to the main P&W company in East Hartford and in May 1958, the first prototype, with military designation YJ60-P-1 commenced testing.Flight tests were completed in early 1959; followed by the delivery of the new JT12A-5 engines in July 1959.