Mistakes
According to "The Doomsday Machine", full impulse drive is one-quarter the speed of light. In the first two movies, Enterprise used thrusters as opposed to impulse drive to leave Spacedock, confirming the notion that impulse drive is far too fast to leave such a (comparatively) small structure. Styles, however, orders Excelsior to one-quarter impulse, which is 18,750 km/s. In one second, she will travel half again Earth's diameter. From the time he gives the order to the time we see Excelsior clear spacedock's doors is approximately 40 seconds. Even allowing 30 seconds to go from rest to one quarter impulse, spacedock must be 13-15 times bigger than Earth! That's some serious engineering. See more...
Trivia
Robin Curtis replaced Kirstie Alley as Lt. Saavik in this film as Alley, who had starred as Saavik in "The Wrath of Khan", didn't want to reprise her role for fear of being typecast. See more...
Movie Mistakes blog
Popular blog posts:
Top 15 biggest Harry Potter film mistakes
30 Biggest mistakes in the Star Wars movies
The 10 biggest mistakes in Iron Man 1 & 2
Other great sites
Star Trek III: The Search for Spock (1984) - 4 quotes
Directed by Leonard Nimoy, starring Christopher Lloyd, DeForest Kelley, George Takei, James Doohan, Leonard Nimoy, Nichelle Nichols, Walter Koenig, William Shatner (add more)
Sarek: At what cost? Your ship...your son.
Kirk: If I hadn't the cost would have been my soul.
McCoy: Yes! Genesis! How can you be deaf with ears like that?!
Kirk: You're suffering from a Vulcan mind-meld.
McCoy: That green blooded son-of-a-bitch! It's his revenge for all those arguments he lost!
[The crew watches the Enterprise burn up in the Genesis planet's atmosphere.]
Kirk: Dear God Bones, what have I done?
McCoy: What you had to do, what you've always done, turned death into a fighting chance to live.