The Robinsons Were Here - S1-E4
Continuity mistake: Penny is holding an envelope in her hands, then turns around to follow the siblings and the envelope is gone. Just a cut later Penny has the envelope back. (00:32:30)
Continuity mistake: Don West is wearing Dr. Smith's necklace, even though it was lost in the storm. The necklace is then not there or removed in the next shot. (00:31:30)
Pressurized - S1-E7
Continuity mistake: When Judy is trying to keep Evan alive in the vehicle, sometimes there is a seat belt across his chest, and other times it is gone. (00:28:00)
Trajectory - S1-E8
Continuity mistake: When John is under the panel with Will, right before Will hands him the flashlight, the way Will is gripping the flashlight changes between shots. His pinky is either on top or underneath.
Answer: The Fortuna didn't have an Alien Engine. The cover story was the Fortuna was to explore Alpha Centauri but it was exploring the rift. The rift is what the Alien Engine creates and explains how the Fortuna was able to travel to a distant planet (what you call "galactic travel").
Bishop73