When on the alien planet, Hawk yells earthquake, but he's never been to Earth.
When the Searcher encounters the Terra-class system and Asimov orders everyone into action, Wilma walk around the command console, directly to the navigation console and takes her seat, all while looking at the monitor - for a blind woman, she manages to not collide with anything or anyone.
When Buck Rogers has flashbacks to the 20th century, his hair is much longer than seen in the previous flashbacks from the first season. This is since actor Gil Gerard grew his hair out for the second season and did not have it cut to match previous episodes where he is shown in the 20th century.
Aboard the Searcher, Wilma has a vision of herself as being blind. We hear "oh my God" but her lips say something else.