If I can't beat you guys, I'll join you!
I was only a kid, and don't remember a great deal but my parents had a bit of an addiction with Yugoslavia between 1987 and 1990, and flew a menagerie of Yugoslav airlines, to take us on our holidays. Think we flew to, Pula, Dubrovnik, Split and Budva/Tivat airports.
We flew JAT twice, on a DC-9 and silver 737-300. Aviogenex, which I think was a 727 and in 1990 we flew Adria on a brand new A320.
The A320 was leased from Cyprus Airways and I think this was one of very few flying back then, as it had literally just been launched and considered how lucky we were...
By contrast we flew the JAT DC-9 the year before, and even back in the late 1980's I remember my parents commenting and calling the aircraft a dinosaur, and think we were delayed in both directions by about 4 hours due to technical problems. All the passengers made a joke and said JAT stood for Joke About Time. I think that is why we was so surprised to fly a brand new aircraft the following year, and was expecting the worst again!
I remember the DC-9 only has a curtain seperating the cockpit and was left open for nearly all the flight.
I think all baggage handling back then was done by either Britannia or Monarch and when you entered the check-in area on the left was a sea of yellow with Monarch Desks and right the blue and white striped Britannia desks. Monarch always did the ground handling for the Yugoslav carriers. Ironically never flew with of these two airlines until 1996 or 1998 respectively from the airport.