Yup. It's a modified Camillus N.Y. 6" pilot survival knife. The first one had the screw on pommel 1957-58 or 59. Then the Camillus peened pommel 6" were made 1959-61. In 1962-66 the Camillus N.Y. 5" pilot survival knife were introduced, and made with the identical "CAMILLUS" over "N.Y." in bold lettering at the ricasso.
In 1967 Camillus Cutlery moved their stamp to the pommel and began dating the PSKs starting with 1967-1. The dating practice was on and off through the years and at one point the Camillus stamp was moved back to the ricasso. However, the Camillus stamp was no longer in bold lettering.
Based on the new stamp/lettering changes, the dates can also be approximately determined. So, your pilot survival knife was approximately manufactured from 1959 to 1961 and likely military issued during the Vietnam war.