Corrected entry: Doc wrote the letter (which was read by himself at the start of the movie) and it mentioned the name Clara. Marty went back to 2nd Sept 1885, and met Clara by the cliffs later on. But that letter was written 1st September 1885, before Marty arrived. How is this possible?
Corrected entry: In the second film, we learn that Marty's future was drastically altered by a car accident with a Rolls Royce, the driver of which apparently suing Marty for damages. When we see the accident, Marty was meant to be racing down a highway, with the Rolls failing to give way coming out of a side street. This means that it was actually the Rolls Royce's fault, and the driver can't have sued Marty. (He would still have broken his hand, but his financial situation would have been much better off in the future).
Correction: Marty's taking part in an illegal street race - had he ultimately participated he'd have been traveling considerably above the speed limit and without anything resembling due care and attention. As such, some if not all of the blame would be attached to him, leaving him completely open to being sued.
Corrected entry: When Doc is telling Clara he is leaving and will not see her again, and he tells her he is leaving in a time machine. Clara tells Doc that she also read the Time Machine and is a fan of Jules Verne, but the Time Machine was written by H. G. Wells.
Correction: Clara says: "I understand that because you know I'm partial to the writings of Jules Verne you concocted those mendacities in order to take advantage of me." At no point did Clara actually SAY that Jules Verne wrote The Time Machine. She does not mention The Time Machine at all, nor would she, as it was not first published until 1895, 10 years after the events of BTTF III.
Corrected entry: In the final scene when Clara hands Doc the framed photo it is completely wrapped in brown paper. A moment later, when Doc hands the gift to Marty the piece which supports the framed picture (allowing it to stand on a table) is visible, even before Marty unwraps the package.
Corrected entry: In 1885 Marty uses the alias "Clint Eastwood." But at the end when Tannen threatens to shoot Doc if Marty doesn't come out to fight, Doc calls Marty by his real name, and no one seems to notice.
Correction: They'd have guessed it's some sort of nickname - like "Doc" instead of "Emmett L. Brown".
Corrected entry: Just before the train hits the inside of the ravine, the train explodes. It shouldn't just explode in midair.
Corrected entry: At the end of the film, Jennifer has the fax from the second movie saying 'You're Fired'. Then, because Marty stood up to Needles, the message erased. However, Jennifer still has the piece of paper. If Marty didn't get fired in 2015, then there would be no fax, and therefore no piece of paper at all. Jennifer shouldn't have had the piece of paper.
Correction: Saying this would mean that the photograph in the first movie would disappear as it would have never been taken, and Doc and Marty never picked up the papers in the second movie, therefore the headlines wouldn't change, rather they'd disappear. But they *do* change, because they did pick up the paper themselves, as a sort of artifact from the future. Jennifer therefore would have brought back the fax paper from the future, but since the fax didn't print when events changed, there would be no message on the paper.
Corrected entry: After Doc went back to 1885, he put the Delorean in an old mine shaft. When Marty went to 1885 to find him he got a hole in his gas tank, and need gas. Well, all they had to do was get some gas out of the Delorean that Doc came back in. Would had saved a lot of time.
Correction: Oil and petrol are normally removed from a car for long-term storage. Although Doc could have kept the petrol he removed... This issue was also dealt with in the DVD commentary, in which it was speculated Doc didn't want to risk reopening the cave, potentially causing a cave-in and thus a paradox if the car can't be retrieved in 1955.
Correction: Gas becomes useless after sitting for a short period unused. It begins to lose its combustibility from oxidation and evaporation, degrading in three to six months.
Corrected entry: In the scene at the start of the movie, the time machine is flying 50 feet or so in the air when it is struck by lightning and sent back to 1885. Later in the movie, we learn that the lightning destroyed the flying circuits. Assuming this is true, as soon as the time machine appeared in 1885, it would have fallen to the ground and been destroyed.
Correction: We can assume a flying car from a future where everybody has a flying car would have some kind of device to get it down safely in event of malfunction. Otherwise, cars would fall out of the sky everytime anyone had a minor problem.
Corrected entry: When the Doc from 1955 is loading up the DeLorian after fitting the new time circuit controls, he hands Marty the walkie talkies. However, in at the end of Back to the Future II the Doc has the other walkie talkie with him. How can Marty have both of them? (00:15:54)
Corrected entry: When Doc and Marty hijack the train, they cut loose the rest of the train but keep the log car attached to the engine. Why? If they're using Doc's special "Presto Logs", then why need to drag an extra car that serves no use? They would've made 88 MPH in record time.
Correction: Locomotives used far more water than fuel. The water was carried in the tender (log car). Therefore, the tender would have to remain attached in order to supply water for the loco during the run.
Corrected entry: In the scene where Mad-Dog Tannen is waiting for Marty to come out of the salon for the show-down, Mad-Dog refers to Marty as 'DUDE', a term which was not used back in 1885.
Correction: Incorrect. Originally the word "Dude" was applied to fancy-dressed city folk who went out west on vacation. In this usage it first appears in the 1870s.
Corrected entry: There is still fuel inside the Delorean which Doc hid in the mining shaft. They could take it without any problems, because it will be found in 1955 and then Doc and Marty can refuel it without any problems.
Corrected entry: When Doc and Marty find the Delorean in the mine, the tires have rotted off with time. It seems that all they had to do to run the car again was replace the tires. However, as any mechanic will know, in that amount of time not just the tires would have rotted. Every rubber hose and gasket, every piece of wire insulation, every bushing and grommet, and many other parts in the car would also need to be replaced. There would be no way to run the car short of completely rebuilding it.
Correction: There were 4 or 5 days between the lightning strike and the trip to 1885. If any car parts needed replacing, Doc could have done it easily. Notice that the DeLorean even sat higher off the ground in the drive-in, suggesting that Doc had to replace the axles. The DeLorean went through a lot of refit to make up for the 70-year storage.
Corrected entry: When Marty time-travels to 1885 and stashes the DeLorean in a desert cave, a black bear inexplicably appears and chases him. There are no bears of any species that inhabit the desert badlands.
Correction: The fictional town of Hill Valley, California, is not in any desert badlands. In BTTF III, a railway map shows Hill Valley as being in Northern California, near the Sierra Nevada Mountains, where there's lots of bears.
Correction: They may not live in the badlands, but they do travel through them. Several years ago, a bear in New Mexico made a journey of 70 miles through the desert from the forested mountains to the Pecos River near Roswell.
Corrected entry: Doc begins telling Marty about his accident with Rolls-Royce, before stopping himself and telling Marty it's better that he doesn't know. How exactly did Doc find out about the Rolls-Royce incident in the first place? When Doc was in the year 2015, he didn't actually talk to Marty or any of his family or Needles, so who told him about the Rolls-Royce incident? At that point, it had happened 30 years prior, so it's doubtful that a minor car crash from 1985 would still be the talk of the town in 2015.
Correction: In BTTF Part 2, they are there to rescue Marty's son going to jail, which in turn puts his daughter in jail. Doc said he did some research and found that the McFly family gets destroyed, that he traced the fall of the McFlys to that incident of Marty Jr committing the crime with Griff. He obviously found out about the accident while doing the research. Even Jennifer found out about the accident by overhearing family chatter, so it was no secret amongst the McFlys. Also keep in mind, in part one Doc does go to the future, but he is back before we see what he was up to. Marty did tell Doc to look him up when he gets there, so maybe he did speak to Marty.
Correction: A Rolls Royce is hardly a minor car to have an accident with. They are such a rare car, one being in an accident in Hill Valley would be unusual enough to be news.
Corrected entry: During the train sequence, when it's pushing the DeLorean, there is a wide shot of the green steam coming out of the train. The steam looks computer generated because it is far too bright and appears slightly away from the train. (01:36:40)
Correction: It may look like CGI, but in fact the widespread use of CGI special effects did not happen until the 1990s. Backdraft, from 1991, was the first use of realistic CGI fire, while Terminator 2 had the first realistic human movements generated by CGI. The train scene in BTTF 3 had some interesting special effects (such as the use of miniatures), but CGI wasn't on the list.
Corrected entry: When Marty finally returns back to 1985 on the finished train track the ravine has been renamed in honor of his alias "Clint Eastwood." But why? The townspeople wouldn't know it was him on the train and Doc wouldn't have been so foolish as to tell anyone "Clint" hijacked the train after becoming a hero from the Tannen fight. It should have still been called Shonash Ravine.
Correction: This is hardly a plot hole, since we don't know what happened after they went through time. It's likely "Clint Eastwood" became something of a local legend. After all, he did beat the toughest guy around. Given all the questions he and Doc were asking about the train, it's not unreasonable to think his legend got tied up with the ravine.
Corrected entry: When Marty asks the Doc if they can take Clara with them to the future, the Doc says no, because you mustn't tamper with the time continuum for your own benefits. However, in the second film, he does change the continuum for Marty and Jennifer's benefits, by going with Marty and Jennifer to change the future, so their son wouldn't go to jail.
Correction: The reason that he says that the space/time continuum shouldn't be tampered with is because of the repercussions of what he did in BTTF II. He is learning from his mistakes, and even says so later on in BTTF III. Plus, he was talking about changing the past and altering history. Changing the future is completely different. The future hasn't happened yet. As Doc said, "your future is whatever you make it."
Corrected entry: The jacket suit that Biff wears in the garage scene in 1985 in Part 3 is red and gray. It is green and gray in the other films.
Correction: The scene in BTTF 1 & 2 takes place on the Saturday morning after Marty returned to 1985. The scene at the end of this film takes place the next day (hence Marty's family think he's been to the lake with Jennifer in his cowboy garb - also check the scenes with the DeLorean showing the time travel destination input). There's no reason Biff should be wearing the same coloured jacket suit.
Correction: The letter never mentioned Clara. They didn't find out about her until they saw the gravestone.
Xofer