I remember as a kid Eastern flew different aircraft types on the same route. In 1963 we flew Eastern from BWI
Back then BWI
was BAL for Friendship International Airport. We went to Miami for 2 weeks in July that year to visit our grandparents. Me, my parents and sister who was 2. My Aunt and my 2 cousins flew with us both ways. The trip from BWI
was a Boeing 720 the return leg was my first flight on a DC-8 complete with curtains and Palomar seats.
Depending on day of week and time of day many times Eastern flew different aircraft types on different days on the same route. Later on you could fly the above route on a 727 or DC-9. As we got into the wide body era Eastern's BWI
flights were usually 727's but on busy days and busier times of year such as Winter and Spring Break you could get lucky and get an L1011 or A-300. I was never that lucky.
On old timetables for many airlines such as Eastern and DL
it would just list jet and there would be fine print saying it could be one of their types of jets. When movies came out, (mid 1960s) airline brochures would highlight an old time movie camera where the reel housings looked like Mickey Mouse ears. And when wide bodies came out Eastern highlighted flights as Whisper-liner
(L-1011) I wish I knew more about PAA's timetables from back in the day.