# Factual question about the movie 'Unstoppable' **URL:** \ **Category:** Factual Questions\ **Created:** [April 26, 2011, 12:40pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756 "2011-04-26T12:40:50Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\ **Post date:** [April 26, 2011, 12:40pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/1 "2011-04-26T12:40:50Z")
So, in the movie Unstoppable, there is (obviously) a runaway train. It has runaway because the engineer mistakenly set it to drive power instead of dynamic braking before he hopped off it to set a switch ahead. Crucially, the air lines to the cars is also not connected. This is the crux of my question. I have, all my life, understood that a train’s brakes were fail-safe, in that, if the air is not applied then the brakes are on. So, from the first moments of this move, I’m crying BS. For the whole rest of the movie, my ability to suspend my disbelief is shattered, despite the fact that the movie is based on an actual event. So, as soon as I finish the movie, I dash over to [IMDB](http://www.imdb.com/title/tt0477080/) to scream and gnash my teeth with the other rail fans about his inaccuracy. Not one word about is written there about the disconnected air line. I go on over to [Wikipedia to see what is written there about both the movie](http://en.wikipedia.org/wiki/Unstoppable_(2010_film)) and the [actual event](http://en.wikipedia.org/wiki/CSX_8888_incident). Turns out, in the actual event, the air hose is disconnected and indeed contributes to the difficulty in getting the train stopped. So now I go to the relevant [Wikipedia article on train brakes](http://en.wikipedia.org/wiki/Railway_air_brake) and they say that train brakes are indeed fail-safe. They should have been applied if they supply pressure is absent. What gives? ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [April 26, 2011, 12:59pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/2 "2011-04-26T12:59:16Z")
> [@UncleRojelio](#): > > What gives? It’s a movie. If it resembled reality, it would be five minutes long and end happily when the failsafe brakes cut in. ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 26, 2011, 1:07pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/3 "2011-04-26T13:07:43Z")
The Engine brakes were applied, but the engine was under nearly full power. Eventually the brakes heated up, so the engine was still able to move, but not at the speeds depicted in the movie. I believe they said it topped out around 45 mph. > **[CSX 8888 - Play - by - Play on the Internet](http://kohlin.com/CSX8888/x-play-by-play.htm)** > > This web page contains the true story of CSX locomotive 8888, an EMD SD40-2 that escaped from Stanley Yard in Toledo,Ohio on May 15, 2001. That link has a lot of eyewitness reports, and [this also gives a comprehensive look at the incident](http://kohlin.com/CSX8888/x-play-by-play.htm). Upon preview: **Mangetout** , you could not be more wrong. This incident did indeed happen. Cops really did try to shoot out the tanks. The train really did blow through the derailing devices. A train really did catch up and slow the train. Oh, and yep- There really _was_ a train of schoolchildren on the same track! ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 26, 2011, 1:09pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/4 "2011-04-26T13:09:00Z")
[Here is a news report on the incident.](http://www.youtube.com/watch?v=-vN6jX4S8v8) ---
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [April 26, 2011, 1:26pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/5 "2011-04-26T13:26:22Z")
Mangetout, the reality was that the CSX 8888 was runaway for 2 hours. Take a look [here](http://www.sdrm.org/faqs/brakes/history/) It seems that the air brakes use air pressure from a reservoir to apply the brakes. They’re fail safe because if there’s a leak in the brake line, it will signal to the valve to apply the brakes, using pressure from the reservoir. If there’s no air pressure at all, there’s no braking. ---
**Author:** ![muldoonthief](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muldoonthief/32/3188_2.png) [@muldoonthief](https://boards.straightdope.com/u/muldoonthief)\ **Post date:** [April 26, 2011, 1:32pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/6 "2011-04-26T13:32:22Z")
> [@Spit](#): > > [Here is a news report on the incident.](http://www.youtube.com/watch?v=-vN6jX4S8v8) I like the shot of the Amish family shaking their heads at the English & their devilish technology. ---
**Author:** ![smithsb](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/smithsb/32/12107_2.png) [@smithsb](https://boards.straightdope.com/u/smithsb)\ **Post date:** [April 26, 2011, 1:52pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/7 "2011-04-26T13:52:18Z")
Thanks Spit. Great rundown of the action and the background. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [April 26, 2011, 2:23pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/8 "2011-04-26T14:23:08Z")
OK, that made me feel deservingly dumb. Worse, I usually hate “Duh it’s a movie!” posts. Sorry. ---
**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\ **Post date:** [April 26, 2011, 2:55pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/9 "2011-04-26T14:55:18Z")
> [@Mangetout](#): > > OK, that made me feel deservingly dumb. Worse, I usually hate “Duh it’s a movie!” posts. Sorry. No problem, I’m usually the “Duh it’s a movie!” poster. But this was different because I thought I knew something about trains that made both the movie and the actual event hard to comprehend. So I guess it turns out that train air brakes are different than truck air brakes. On a truck, the air holds the brake shoes away against the force of giant springs. On a train, there are no giant springs to activate them in an emergency. Air is required from storage tanks. It appears that cars sitting in a yard often don’t have air in the storage tanks. In the actual event, the disconnected air line meant that the storage tanks were not getting charged and, subsequently, were not able to be applied even when the engineer set them before leaving the cab. However, the act of setting the (useless) brakes also disabled the engine’s ‘alerter’ system which would have shut it down after a set time limit. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [April 26, 2011, 3:49pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/10 "2011-04-26T15:49:58Z")
> [@UncleRojelio](#): > > So I guess it turns out that train air brakes are different than truck air brakes. What I understood here is that the air brakes to the cars were intentionally disconnected, which apparently is normal when moving around in the train yard. Only the locomotive’s brakes were functional. ---
**Author:** ![sunacres](https://avatars.discourse-cdn.com/v4/letter/s/4491bb/32.png) [@sunacres](https://boards.straightdope.com/u/sunacres)\ **Post date:** [April 26, 2011, 8:28pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/11 "2011-04-26T20:28:18Z")
Like the OP, I was also crestfallen when my disbelief could not be maintained. I couldn’t even finish the movie. But it wasn’t the braking that I had trouble with. Why didn’t the veteran engineer who originally tried to slow the train down from the front just walk down and get in the cab? ---
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [November 19, 2011, 4:20am UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/12 "2011-11-19T04:20:37Z")
> [@sunacres](#): > > Why didn’t the veteran engineer who originally tried to slow the train down from the front just walk down and get in the cab? Resurrecting this because I just watched this movie and that’s almost exactly the thought I had during that scene. They seriously didn’t think to put someone else on that engine to climb over and stop it? Yeah, I know that part was entirely fictional. That said, I thought it was a _great_ fucking movie. ---
**Author:** ![Max\_Torque](https://avatars.discourse-cdn.com/v4/letter/m/e9bcb4/32.png) [@Max\_Torque](https://boards.straightdope.com/u/Max_Torque)\ **Post date:** [November 21, 2011, 3:08pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/13 "2011-11-21T15:08:56Z")
In the somewhat older movie **Runaway Train** , the engineer has a heart attack and falls out of the engine, applying the brakes as he does so. Unfortunately, the throttle was wide open, so basically the brake pads (or whatever similar things trains have) just burnt off, after which braking was no longer an option. I’d assume something similar. ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [November 21, 2011, 3:21pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/14 "2011-11-21T15:21:16Z")
I thought even then (talking about _Runaway Train_) throttles had a dead-man’s switch kind of configuration. ---
**Author:** ![BlakeTyner](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@BlakeTyner](https://boards.straightdope.com/u/BlakeTyner)\ **Post date:** [November 21, 2011, 6:58pm UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/15 "2011-11-21T18:58:01Z")
They do (and this is also something of a gripe for “Unstoppable,” too.) The older locomotives in “Runaway Train” would have been equipped with either a dead man’s pedal (used in the Wilder/Pryor “Silver Streak”) or an alerter. The alterter is basically an alarm that sounds in the cab every XX seconds unless the engineer is manipulating the throttle, brake, horn, etc. The engineer has XX seconds to hit the “Alerter Reset” button. If he doesn’t, the train will apply the brakes and stop. Now, in both “Runaway Train” and “Unstoppable,” the automatic brakes (railroad lingo for the brake system on the locomotives and all the cars) were not an option: they weren’t tied in for “Unstoppable” because the train was just supposed to be a yard movement, and in “Runaway Train,” as mentioned, the throttle was wide open, which burned the brake shoes away. Thing is, though, is that the alerter wouldn’t just apply the brakes–it would also cut out the traction motors. What this means is that, even without the brake application, the train would no longer be under power from the locomotives. Usually, unless we’re talking about steep grades, this would slow the train and probably eventually cause it to roll to a stop. One other nugget to complicate matters–in “Unstoppable,” the hostler engineer had applied the “independent” brake, which only controls the brakes on the locomotives, to its full position. In most or all cases, this action disables the alerter feature. I believe the movie shows the throttle lever dropping wide open by itself after the hostler leaves the cab (I won’t call that impossible, but I’ve never heard of it happening before) and possible shows the IND brake lever dropping to release–if the latter, then the alerter functions should have cut back in. Believe it or not, my Master’s thesis was about “Runaway Train” and “Silver Streak.” ---
**Author:** ![SCSimmons](https://avatars.discourse-cdn.com/v4/letter/s/e495f1/32.png) [@SCSimmons](https://boards.straightdope.com/u/SCSimmons)\ **Post date:** [November 25, 2011, 3:01am UTC](https://boards.straightdope.com/t/factual-question-about-the-movie-unstoppable/579756/16 "2011-11-25T03:01:24Z")
> [@BlakeTyner](#): > > One other nugget to complicate matters–in “Unstoppable,” the hostler engineer had applied the “independent” brake, which only controls the brakes on the locomotives, to its full position. In most or all cases, this action disables the alerter feature. I believe the movie shows the throttle lever dropping wide open by itself after the hostler leaves the cab (I won’t call that impossible, but I’ve never heard of it happening before) and possible shows the IND brake lever dropping to release–if the latter, then the alerter functions should have cut back in. According to the accounts at the very informative site linked by **Spit** (his second link in post #3), the official story is that the engineer thought he had applied the dynamic brakes in addition to the independent, but had actually put the throttle to max instead. Some of the cites there question this story on several grounds: [ol] [li]The throttle and the dynamic braking lever, while adjacent, move in opposite directions–the dynamic brake lever would have been pushed up to engage, but the throttle was pulled down.[/li][li]The sounds of the engine engaging and the dynamic brakes engaging, while both loud, are very different, and the engine is much louder–the engineer should have realized his mistake instantly.[/li][li]Dynamic braking is pretty much useless at yard speeds; it’s similar to engine braking in a car, using the engine power against the turning of the wheels instead of for it. When the train is idling, the dynamics provide little or no braking power.[/li][/ol] Also, in the real incident, the independent actually was set, which kept that train from ever reaching the speeds of the fictional train in _Unstoppable_–but did disable the alerter. It was still fast enough & heavy enough to shatter the portable derailleurs, though.