I've seen plenty of poorly executed sci fi films I can't help but be impressed both by how terrible this film is and how much effort was put into it.
Based on a 1977 short story this project came into production in 1979 but passed between a handful of directors and studios before finally reaching theaters in 1989. This was clearly a passion project that was taken extremely seriously during production but the end result is a jumbled mess that ineffectively tells a story about time travelers from 1000 years in the future interfering with a plane crash in our time. There probably is a right way to tell this story but they weren't able to find it.
I'd be hard pressed to find a crazier disaster of a film than this one. I could even go so far as to say that this movie is BONKERS.