Ops and Instrumentation Then and Now
Some of the posts herein that answered follow on questions did not clarify if the answer applied to today's ops environment or what KLM/PA/B747 had in place in 1977.
Regardless, I would like to broaden my original post.
Whether in 1977 or now, I take it commercial aircraft did not have a radar system to see planes around them. Since most of the flight time was at FLs above the clouds, the pilot and copilot could probably visually see what's ahead of them by day, and if the aircraft were illuminated, what's ahead by night. To wit, no radar system needed. Is my reasoning correct?
With all aircraft now using transponders to identify themselves, is there an on board system today that maps where other planes are in the vicinity around a given plane? If so, how far out? Does the transponder also flash FLs?
Also at night, is it standard practice to fly dark? I know Air Force One frequently does, and it was reported KAL 007 also was dark -- no wing or tail lights whatsoever, but that could have been Soviet propaganda to help justify the downing of that aircraft.