Thanks. The Metroliner from what I could find did have a jet assist option at one time. In said 1969 the jet assist on it may have been a short lived thing for passenger air service on this aircraft. I distinctly recall a JATO type sensation with a high noise level like that of a jet engine that lasted around ten seconds during take off. As mentioned, had a previous JATO flight on a C-123 in South Vietnam in 1967.