According to the Observer's Book of Aircraft (William Green, 1969 and 1980 editions) the first 747-200 rolled off the production line in October 1970, just months after the original 100s (from about the 80th airframe onwards). The 747-100 had a range of about 4600 miles with full fuel and regular payload. The -200 series had a range of 6600 miles, supposedly, but with a light payload (and 7080 miles with full fuel and almost zero payload).

I am thinking that the longest flights in the early 80's would have been the LAX to LHRs and similar. Even Qantas (without the SP) had to stop in HNL between Australia and the US. BA's timetable from 1990 still lists flights to NRT as being via ANC (but does show F class now as 62' sleepers on the 747-200 and -400, with the L10 and DC10 still numbering about 20 in their fleet).

I believe the fist non-stops between asia and Europe were by SQ in the 747-300s?

Regards

lme ff