Originally Posted by
Toshbaf
KLM, DC-9
My guess is that by around 1980, KLM operated non-stops SXF - AMS.
EDIT: While posting, I see WHBM posted Aeroflot with an IL-62. I agree. I know KLM didn't start non-stop SXF-AMS until the late 1970's or early 1980's and a one stop in FRA is very unlikely.
I remember in the early 1970s seeing a weekly (?) KLM Electra flight AMS-SXF-WAW, with the Berlin stop not mentioned in the published timetable, no doubt to avoid upsetting the allies and West German government. Where would I have seen this? Possibly at the Amsterdam or East German airport or at a travel office in Berlin. It was probably in 1971, since that December I was returning from West Berlin to New York, had booked a cheap KLM round-trip from Amsterdam and was looking at how to get to Amsterdam. In 1971 getting to SXF for the KLM flight was probably too complicated or even disallowed, so I took the overnight (Soviet) sleeper (Moscow-Berlin-Hook of Holland) instead.