I was at a Blue Angels air show practice at Pensacola in July 2006. Prior to the Blue Angels show, a number of the T-39 Navy navigation trainers took off for their training exercise. The retired naval folks hosting the show told us that these Saberliner trainers were being piloted by retired naval aviator contractors.
I had worked on the JT12's as a PWA
research engineer (East Hartford) in the mid-sixties and remembered the JT12 whine (about 16,100 rpm) at takeoff power.
Thanks for bringing up one of my 40+ year old memories....