Thanks Airbubba; I strongly believe that the earlier incident involved a DC9 / MD because of its servotab control system, which at that time related to the aircraft in my operation (146 / RJ), 1980-90s.
Was the DC8 elevator / pitch control a conventional aerodynamic servo tab system?
Based on the photos so far, it is difficult to understand how a restriction so significant that it prevented rotation, could not be detected before flight.