Factual error: When Chekov and Uhura first see USS Enterprise and then later beam aboard, the carrier shown is not USS Enterprise (a nuclear aircraft carrier), but rather USS Ranger (a conventional or oil-fired carrier). The most obvious clue is the "island", the huge structure that sits on the deck of the carrier. USS Enterprise has the most distinctive and unique island of all the USN carriers, being totally cube-like in appearance. The carrier in Star Trek IV has a more conventional style island. [It is true that the USS Ranger was used in lieu of the USS Enterprise for the movie. This is because the Enterprise was on deployment at the time. Though by the time the movie was made the Enterprise had had its distinctive pagoda-like island rebuilt by Puget Sound Naval Shipyard in 1980, the aircraft carrier served until 2012 with a still-distinctive cube shaped island.] (00:53:30)
Factual error: The nuke ETs are sitting at a RADAR station, not a power output monitoring station. The RADAR wouldn't give any sort of indication of sudden additional power draw on the reactor. (01:12:00)
Factual error: They are about to perform major brain surgery on Chekov, but he is not nearly prepped for such a procedure. His head is not shaved, the area is not marked or masked and it has not been swabbed with Betadine, even though they are about to cut into his skull with a bonesaw. The "they haven't had time to prepare yet" argument doesn't hold water, because the surgeon is already approaching Chekov's head with the saw. (01:24:30)
Factual error: Scotty is listed in the credits as Captain Montgomery Scott. At the end when the camera pans the crew just before their pardon, Scotty wears the rank pin of a Commander (the same one worn by Commander Sulu, Commander Chekhov, and Commander Uhura). (01:48:55)
Factual error: The "whaling boat" is too small to function as such. It isn't large enough to hold a fin, let alone disassemble a humpback whale.
Factual error: At two points in the film, the Klingon vessel Bounty traverses the distance from the Earth to the Sun at maximum speed, in excess of Warp 9. The latter sequence requires about 111 seconds from the time Sulu says "Aye sir, warp speed" until they reach the Sun. While there is no real science behind Star Trek's "warp technology, " the Starfleet Technical Manual provides a formula for calculating warp speed, whereby Warp 9 translates to about 136 MILLION MILES PER SECOND. The Earth is only 93 million miles from the Sun. In the apparent time that it takes the Bounty to reach the Sun, a starship traveling at such ferocious velocity would already be outside of our known solar system and deep into interstellar space.
Factual error: When the Bounty is preparing to slingshot around the sun, the sun is burning a light yellow. From space, it would be white; it only appears yellow when viewed from Earth because of how the visible color spectrum is filtered through the atmosphere.
Factual error: As they descend into the park, Uhura gives a bearing and range of 283 degrees, 15.2 kilometers to the whales, which are supposedly in a marine park in Sausalito. 283 degrees would put you in the Pacific Ocean, because Sausalito bears around 360 degrees from the park. Uhura gives a true bearing to the whales, since a relative bearing would be useless once the crew leaves the park.
Chosen answer: This question has been answered a number of times by various individuals, all saying pretty much the same thing. The answers have been most satisfactory given the question revolves around a fictitious situation and the answer (s) need to be accepted as complete for this purpose. Any dispute or non-acceptance should be addressed in a Star Trek forum. Any ignoring of the Prime Directive was done to save the future of Earth, as the probe would have wiped out all life on Earth. Essentially, nothing that was done in the past resulted in major changes that would make Earth 300 years later appear any different, and no major futuristic technologies were revealed. The major one, Chekov's communicator and phaser being left behind did not result in anybody learning secrets. In the film, the phaser didn't function because of the radiation. It's presumed then the radiation permanently damaged the equipment so it appeared to be nothing but a toy or prop. However, in the novel "The Eugenics Wars: The Rise and Fall of Khan Noonien Singh", Roberta Lincoln was sent by Gary Seven to recover the items from Area 51 before any secrets were learned (and as stated before, additional corrections to Earth's timeline could have been done that aren't addressed in the film.) The subsequent loss of a suspicious "ruskie" would have hardly affected the era that was already in the midst of the Cold War. McCoy even questions that giving Dr. Nichols the formula for transparent aluminum could alter history to which Scotty replies what if Dr. Nichols is the one who invents it, to which McCoy agrees (in a later novel it is reveled that Scotty already knew Dr. Nichols invented transparent aluminum, so history was not changed.) The miraculous recovery of the old lady (growing a new kidney) was done by a pill so that any examination of her would not reveal the futuristic method involved. She would be a bewilderment to the medical community at best, and most likely misdiagnosis would be to blame. And just because she got a new kidney does not mean her life would have been extended, she could have died some other way in both timelines. And as stated before, Gillian simply wasn't vital to Earth's history. She could have contributed nothing of importance to society and died alone and childless. And a missing pair of breeding Humpbacks would hardly affect the extinction of their species, however in the future, they are already extinct, so little changes would occur. As for any questions about people seeing the Klingon ship in the past, who would believe them? People have long been claiming to see spaceships and aliens to little or no avail, so why would anyone believe a handful of people who said they saw aliens in a spaceship steal 2 whales? However, as with many time travel situations in films and novels, it's possible the events of the 23rd century as they appear in the beginning of the film are a result of Kirk and company's actions in the 20th century since the events already occurred even though Kirk and company had not yet done it themselves (this is where a discussion forum on the film would be advised, or a discussion forum on the theories of time travel).
Possibly the most convoluted and poorly-reasoned series of answers I've seen on this site. So far.
Charles Austin Miller
I think they're pretty logical actually.
I think your opinion would be in the minority. There is nothing exceptionally convoluted, nor poorly reasoned in the response.