The crew count is inconsistent from In the Flesh (1998). In that episode, the Doctor mentions that he has to run DNA scans for 125 crew members besides Chakotay and Tuvok, which would imply a crew count of 127 (excluding himself), yet in this episode, the future Harry Kim mentions how he sent 150 people to their deaths. Chakotay also mentions 150 people when speaking to Captain La Forge.
The Doctor says Seven of Nine died on stardate 52164.3, however Captain Janeway says the stardate in her log is 52143.6. Clearly an error in the stardate here.
Janeway delivers future Harry Kim's message to Ensign Kim stored on a tricorder. Tricorders are not used to transport media files. They have data PADDs and Isolinear circuits for that purpose.
The pause in the message Harry leaves for his past self changes place.
In season 4's "Hope and Fear" it's been shown that the slipstream remained intact for an hour before it collapsed. If it was that way for an hour then they would not need phase corrections to get them through the slipstream in the first place. Clearly a mistake by the show runners. They changed how long and far they go with the same form of propulsion.
Paris says that he's detecting a planet 9 million kilometers away, and they crash on it seconds later. Full impulse, or one-fourth the speed of light, is 75,000 kilometers per second, which would put the planet a rather leisurely two minutes away.
At the celebration in Engineering, Seven of Nine appears to be intoxicated after one glass of synthehol. Numerous episodes of Star Trek have established that synthehol mimics the taste of alcohol with no intoxicating side effects.
When the slipstream drive is first introduced to Voyager in the previous season, a recorded, albeit fabricated, message from Starfleet claims that the slipstream trip home would take three months. When Voyager is knocked out of slipstream after a flight of only a few minutes they are shown to be on the outer edge of the Alpha Quadrant, which implies that the trip home would take far less than three months.
It is said that Voyager was buried under 20 meters of ice. At that thickness, it would not be possible to see the ship, especially not as clearly as it is seen here.
According to Star Trek creators, full impulse is 1/4 the speed of light. While exploring Voyager under ice, Chakotay says it looks like the ship hit the surface at full impulse; but, in the shot of Voyager crashing, it is clearly not traveling at 1/4 the speed of light; however, the version of the crash shown takes place in a timeline that had already been altered.
When Tom and Harry conduct the holodeck simulation, Tom tells the computer to "freeze program," yet, after he does, a holodeck-created bridge panel behind him continues to blink off and on.
The Delta Flyer is scaled too large in comparison to Voyager. At the size shown, it would not fit inside Voyager's shuttle bay.
The scaling issue is even worse when the Delta Flyer is shown in comparison to the Galaxy-class USS Challenger. The Delta Flyer is even larger compared to the Challenger than it was in comparison to Voyager. A Galaxy-class ship is several times the size of an Intrepid-class ship like Voyager.
The scaling issue is even worse when the Delta Flyer is shown in comparison to the Galaxy-class USS Challenger. The Delta Flyer is even larger compared to the Challenger than it was in comparison to Voyager. A Galaxy-class ship is several times the size of an Intrepid-class ship like Voyager.
When Chakotay and Tessa perform evasive maneuvers to get away from the USS Challenger, the stars outside of Tessa's window don't move.
The scale of Harry and Chakotay standing on the ice above the frozen Voyager is way off. They are much too large given the ship's size.
Captain La Forge is ostensibly speaking to Chakotay from the bridge of his ship, as would be proper in the situation. The set behind him is clearly not the bridge of the ship. Not only does it not match the layout of a Galaxy class ship, as seen in Star Trek The Next Generation and Deep Space Nine, but there are observation windows visible in the background. There are no observation windows at the rear of the bridge of any Starfleet ship, nor is it of a style of window of a captain's ready room. Even if the layout of a ship's bridge was meant to have changed over the course of the previous 15 years of this future timeline, the exterior shots of the USS Challenger show no such alterations.
When Seven of Nine is revealed to the Doctor in the Delta Flyer after they (Chakotay and Harry) explained the situation, the "corpse" of Seven of Nine has a pulse in her neck.
Numerous pieces of cloth and transparent plastic film are visible being used to protect the set from all the fake snow and ice dressing in the frozen crashed ship.
The slipstream becomes unstable after a short period of time-- but there is no reason why it couldn't be used for short bursts repeatedly.
Voyager is stated to be in danger of hull collapse in the airless, near-vacuum of space but is supposed to be "fine" if it lands on a planet with enough of an atmosphere to have deep snow and permanent ice coverage. That doesn't make sense.
Voyager seems to leave the slipstream at a similar point in time during all three timelines. In the first two, it crashes on a planet near the Alpha Quadrant. In the third timeline, the ship and crew survive, but they are left nowhere near the Alpha Quadrant. Presumably, this is done for the story's sake, but they should have been let out of the slipstream a lot closer to the Alpha Quadrant.
In the original timeline, Voyager fell out of the slipstream but the Delta Flyer still made it back to the Federation. In the new timeline, Voyager falling out of the slipstream somehow caused the Delta Flyer to drop out of the slipstream as well. Either the Delta Flyer was dependent on Voyager for the slipstream and should have dropped out in the original timeline, or it had its own slipstream abilities and should have kept going in the new timeline.
The first time that Kim and Chakotay attempt to change the past, they fail but the future remains the same. Any possible changes to the past the would definitely change the future, meaning that their mission would have been different or even nonexistent.
Janeway refers to the slipstream drive as the next advancement in the field of "in stellar" travel. She clearly meant "interstellar."