Those “visiting airliners” were unscheduled, and normally emergency landings or ‘’precautionary landing” due to mechanical failure.
We were served by Reeve's Aluetian Airways while I was there in 1977. That's how they flew most of us into the island. I did fly in C-130's, but that was mostly water patrol with the Coast Guard. Their job was to make sure all the fishing boats were where they should be while fishing for king crab.
We did fly out to Attu one day. Got a tour with the base commander in a land rover over the terrain where the Japanese and Americans fought the longest sustain battle of the second world war. Fascinating.