Train going 55 mph

[Dan O]

Does a train create suction when it is zooming along at say 55 mph? If so, how close would an object have to be to be "sucked" into the train? And how long would the train have to be? Would a passenger train be long enough?

If suction is created, would a person holding something large (4 feet x 4 feet piece of wood) be "sucked in?" How close would they have to be?

Dan

 

[TacoMan]

Sounds like a question for Physics class. lol

 

[BobWeaver]

Typically anything close to the train's path will be blown away by the wind from the locomotive. I've never experienced much wind force that draws me closer to a train as it passes, but when the rear car passes, there is a difference in pressure, presumably from air rushing to fill the void that was just taken up by the last car.

 

[gswager]

Mythbusters had an episode about that, in cooperation with NM Rail Runner. I think it just blow you away, not suck in.

 

[GG-1]

Aloha

When I was 6 I was on a local station Platform when a GG-1 passed on the express track, one over. the air/wind almost blew me over, then as the train passed I felt the suction. I was scared and excited. A long time later I learned that section of corridor traffic the g's typically ran at 100mph.

 

[the_traveler]

I experience the "wind" of the AE zipping thru the KIN station at 150 MPH all the time. What I feel is the wind of the locomotive pushing the air out in front of the train. But never any suction of the train pulling things in!

The station platform is about 12-15 cars long. At the east (north) end is a bridge. When standing at the west (south) end and a northbound AE passes, the AE can be under and past the bridge before I even feel any suction (such as blowing leaves) from the train!

(The AE is only 5 cars and 2 power cars long.)

 

[Devil's Advocate]

When I was a young boy my father and I were once trapped on a roughly four foot wide section of brick pathway between two ATSF freight trains traveling at full speed in opposite directions. There was substantial wind and noise in all directions, but not enough to suck anyone under the wheels or anything. Merely remaining calm enough to avoid moving any closer toward either train was the simplest method for survival in that situation. It was not very fun but eventually it was over and I was able to escape my situation unharmed.

 

[Dan O]

I did a search and found a few headlines where it said a person was sucked into a train. Both cases I found involved the person that died had been very drunk. I think that does little to make me think that they really were sucked in.

Did find this summary of Mythbusters show...thanks for the tip.

Although small scale testing with model trains in a wind tunnel showed a vortex, the more dominant force when running the full size train was the air turbulence running alongside and away from the train. The force caused Ted, a dummy made of ballistics gel, to simply fall down where he stood rather than be drawn into the train’s wake, and also violently pushed around an empty stroller tethered onto the platform alongside. Despite the lack of suction, the MythBusters agreed that the turbulence was powerful enough in its own right to make standing that close to the train as it passes very dangerous.

Not a physicist or someone who has experimented at all but am thinking that initially the train would be pushing air away from it and only near the end or after it passed would there be a rush of air back toward the tracks. Even then, not so sure it would be as powerful as the initial push away from the tracks.

Thanks for the replies.

Dan

 

[TacoMan]

To me the speed would have to be that of something like a 200mph Bullet train or faster to really create a vortex behind it.

 

[Shanghai]

I experience the "wind" of the AE zipping thru the KIN station at 150 MPH all the time. What I feel is the wind of the locomotive pushing the air out in front of the train. But never any suction of the train pulling things in!

I'm surprized you could see the Acela traveling through KIN. I was on the Acela twice last week and I could

not see the KIN station as we alledgly zipped by. I think Penny had the same experience one week earlier.

Perhaps you should install a LARGE sign saying Kingston, RI, home of the-traveler!!

 

[jis]

I'm surprized you could see the Acela traveling through KIN. I was on the Acela twice last week and I could

not see the KIN station as we alledgly zipped by. I think Penny had the same experience one week earlier.

Perhaps you should install a LARGE sign saying Kingston, RI, home of the-traveler!!

Hey! Don;t knock KIN! It just got funding for full high level platforms and a third platform track in this last round of HSR funding!

 

[Spokker]

I'm surprised that people who still ask this question are even patronized, especially on a forum dealing with trains.

It's another one of those old myths that people make up about things they have little experience with. People make up stories about how the train will suck you under the wheels and kill you if you stand too close, but we do very little about real dangers such as those dangers associating with the automobile.

I wish people would ask and talk about the question, "If is true if you drive too fast you might run over someone in a crosswalk and kill them???" It would be far more productive than inane questions about train vortexes.

 

[AlanB]

I'm surprised that people who still ask this question are even patronized, especially on a forum dealing with trains.

The very reason that this forum exists is so people who don't know anything about trains & Amtrak can come here to ask questions; even questions that may appear inane to someone who does know all about trains.

Yes, many people who do know all about trains also come here to discuss Amtrak and other train stuff, and many also answer those questions put up by those who don't know. I've always been a firm believer that no question is too stupid if you don't know the answer; the only stupid thing is to not ask and consequently learn.

But again, this forum and this website were started with the purpose of being able to ask questions and it remains a primary goal of this forum to host & allow such questions. If you find the questions inane; fine, just don't answer please and let someone else answer.

 

[Dan O]

The very reason that this forum exists is so people who don't know anything about trains & Amtrak can come here to ask questions; even questions that may appear inane to someone who does know all about trains.

Thanks.

Someone actually told me this happened to them. I had some doubts regarding the story. I aim to give people the benefit of the doubt when I hear something that doesn't sound all that credible. I was just checking here to see if there was any reason to give this person any reason to believe him.

Thanks again to all who posted,

Dan

 

[jis]

One of the characteristics of being a good student is to ask questions and then dig in a bit, instead of depending on a TV show for answers.

The answer about wake vortex associated with HSR is as expected not simple. It depends on the ambient conditions and wind flows in the ambient relative to the train. Without further comments take a look at:

An example of what happens under cross wind conditions:

http://iawe.org/Proceedings/CWE2006/TB3-02.pdf

And how under certain conditions there can be negative pressure generated in the wake:

http://www.ara.com/Projects/SVO/Papers_white/train_aero.pdf

A personal anecdote which has some relevance to this discussion.....

In my graduate school days at Stony Brook I had the incredible fortune of attending a lecture given by the great Nobel Laureate Physicist Richard Feynman. Had the incredible humbling experience of talking to the great man whose Masters Thesis was what turned out to be the beginning of an entire area of Physics called Quantum Electrodynamics! Allegedly he also entertained himself while involved with Project Manhattan at Los Alamos by picking locks of cabinets holding highly confidential documents and leaving pithy notes like "Guess Who?" in them, sending the security folks into a tizzy.

In the conversation he pointed out that there is no question that is inherently stupid. The issue is whether one wants to dig in and see the nuances associated with the question or not, i.e. are we good students or have we come to the position of Mr. Know It All already You know that you have become a true good student when you are at peace with the realization that the more you know, the more you know what you are yet to learn and know. That is the nature of the beast and what makes life fascinating.

Anyway, there are several other papers on this subject of wake vortices that I have access to through my professional memberships, but they cost mucho dinero, so I won't giver references to here.

 

[pennyk]

One of the characteristics of being a good student is to ask questions and then dig in a bit, instead of depending on a TV show for answers.

The answer about wake vortex associated with HSR is as expected not simple. It depends on the ambient conditions and wind flows in the ambient relative to the train. Without further comments take a look at:

An example of what happens under cross wind conditions:

http://iawe.org/Proceedings/CWE2006/TB3-02.pdf

And how under certain conditions there can be negative pressure generated in the wake:

http://www.ara.com/Projects/SVO/Papers_white/train_aero.pdf

A personal anecdote which has some relevance to this discussion.....

In my graduate school days at Stony Brook I had the incredible fortune of attending a lecture given by the great Nobel Laureate Physicist Richard Feynman. Had the incredible humbling experience of talking to the great man whose Masters Thesis was what turned out to be the beginning of an entire area of Physics called Quantum Electrodynamics! Allegedly he also entertained himself while involved with Project Manhattan at Los Alamos by picking locks of cabinets holding highly confidential documents and leaving pithy notes like "Guess Who?" in them, sending the security folks into a tizzy.

In the conversation he pointed out that there is no question that is inherently stupid. The issue is whether one wants to dig in and see the nuances associated with the question or not, i.e. are we good students or have we come to the position of Mr. Know It All already You know that you have become a true good student when you are at peace with the realization that the more you know, the more you know what you are yet to learn and know. That is the nature of the beast and what makes life fascinating.

Anyway, there are several other papers on this subject of wake vortices that I have access to through my professional memberships, but they cost mucho dinero, so I won't giver references to here.

Jis, are you sure you are NOT a Nobel Laureate? :lol:

Thanks for your well reasoned and researched responses (even if most of them are above my head).

 

[Devil's Advocate]

Folks reading this thread should also keep in mind that although it's unlikely to be physically sucked into a moving train there are other ways you can be harmed if you're standing too close, even with conventional freight trains traveling at less than full speed. Branches and other debris can get stuck in the train and then come flying along the side of the train and smack you around. You can also have any number of materials in open top cars that can hit a small defect in the rails or catch a gust of wind and come flying off the car at the train's current speed. In the winter ice can form on stationary cars which can come flying off later when the train is at speed. The cars on any given train can come from many different owners and leasers and they don't always keep their maintenance up to identical levels. Who's to say some part of the car isn't bent slightly beyond the original width and sticking out just far enough to give you a very nasty surprise. And finally if you just happen to be a slightly clumsy individual it only takes one wrong step too close toward a moving train and you could easily be missing a limb or two or be dragged to your eventual death. That's not to say that any of these situations will occur with any particular frequency, but they do happen and there will be nobody to blame but yourself if any of them eventually befall you. Bottom line is that you're unlikely to be sucked into a moving train, but that doesn't mean there is no risk involved. If you really want to get a close up look at a passing train speeding by I would suggest using a video camera on a tripod that is secured well enough not to tip over. That way even if you misjudge something it's only your camera that requires attention.

 

[jis]

Jis, are you sure you are NOT a Nobel Laureate? :lol:

Thanks for your well reasoned and researched responses (even if most of them are above my head).

Yep, quite sure I am NOT, and quite sure that I never came anywhere near by orders of magnitude ever either. All that I have personally achieved is either to be able to explain something simply or to have the humility to say that I don't know enough to explain it simply, and perhaps point out a few issues that need to be considered - the "student" thing I mention above.

Very often when these questions come up I find myself digging back into my graduate school in Physics days 34 years back and remaining connections from that period, to try to figure out how those things apply to the situation one is asking questions about. Currently it is just a hobby to kill time when there is nothing more interesting like riding trains or hiking in mountains, to do. Thanks for your kind words.

 

[Spokker]

But again, this forum and this website were started with the purpose of being able to ask questions and it remains a primary goal of this forum to host & allow such questions. If you find the questions inane; fine, just don't answer please and let someone else answer.

The question is not only inane but insulting. It's a question based on a myth that trains are unsafe, in this case, unsafe for pedestrians to be around.
Trains should be put underground. They shouldn't be built in our community. A train is a death trap. Grade crossings are dangerous. Trains should not run through a station at full speed. That's the kind of nonsense this stuff perpetuates.

But I never said the question should not be asked. I'm simply surprised more people aren't speaking out strongly against this vortex myth.

 

[the_traveler]

(even if most of them are above my head).

Most are, Penny!

That answers why you took the AE from WAS to BOS and back! Both stations are stub end tracks, so you could not go the wrong direction!

 

[Devil's Advocate]

The question is not only inane but insulting.

The only person I see insulting anyone else is you.

A train is a death trap. Grade crossings are dangerous. Trains should not run through a station at full speed. That's the kind of nonsense this stuff perpetuates.

If anything Amtrak Unlimited has opened my eyes to the far larger number of folks who are harmed or killed by trains on a regular basis than I previously realized.

 

[Spokker]

If anything Amtrak Unlimited has opened my eyes to the far larger number of folks who are harmed or killed by trains on a regular basis than I previously realized.

We worry about train suction and getting hit by lightning and and being eaten by sharks and dying in a suicide bombing while many people are killed by unsafe driving every single day. And then we have people crusading against cell phone tickets, red light cameras, the 65 MPH speed limit and police officers doing their job by handing out speeding tickets.
We as a society generally worry about the wrong things.

Here's a good article about risk as it relates to energy: http://www.thecitizen.co.tz/editorial-analysis/20-analysis-opinions/9258-risk-educated-civilised-people-dont-necessarily-understand-it.html

Hundreds of miners die every year digging the coal out of the ground, and hundreds of thousands of other people die annually from respiratory diseases caused by the pollution created by burning it. In the long run, hundreds of millions may die from the global warming that is driven in large part by greenhouse emissions from coal-fired power plants. Yet people worry more about nuclear power.

 

[Devil's Advocate]

We as a society generally worry about the wrong things.

I've made the same claim in my own posts, but we as a passenger train forum are likely to discuss any number of threats both to and from train operation, including those that may not have a strong basis in reality or may have developed from myth or fantasy.

Hundreds of miners die every year digging the coal out of the ground, and hundreds of thousands of other people die annually from respiratory diseases caused by the pollution created by burning it. In the long run, hundreds of millions may die from the global warming that is driven in large part by greenhouse emissions from coal-fired power plants. Yet people worry more about nuclear power.

I would like you to explain to a simpleton like me how swapping a few thousand years of global warming for millions of years of dealing with mountains of nuclear waste is such a great deal, because neither option sounds like anything I want to be a part of. Please include factors such as half-a-century of continuous transport by train and truck being required to move the waste we've already generated and another half-century of constant transport for the stuff we're still creating today. Be sure to include routine truck and train accidents along with uncontrolled releases of long-lived nuclear material every few years or so. It would also be nice to include all the foreign sources of proper grade fissile material managed by both friendly and not-so-friendly governments we'll soon be funding just like we've been doing with our ever growing need for oil. Then when you're done with that perhaps you can explain why domestic sources of energy like wind, solar-thermal, solar-voltaic, geothermal, conventional natural gas, and efficiency improvements won't work. And finally I'd like you to go back and reconsider the original premise by reviewing which coal plants are competing with which nuclear plants, because from what I've seen nuclear plant funding generally competes with renewable energy sources and not fossil fuel sources.

 

[Spokker]

Just because a person holds one opinion doesn't mean they automatically hold another. I believe very strongly in renewable energy. I would never explain to anyone why wind, solar, etc. won't work in the long term because I don't hold that view.

The point isn't about coal or nuclear or energy sources per se, but that we hype up future risks of low probability or reoccurrence (nuclear meltdown, getting sucked into a train, plane crash, lightning, shark attack, terrorist attack, child abduction etc.) while playing down very real current risks (global warming and coal, car accidents, looming debt both personal and public, obesity epidemic, etc.).

 

[the_traveler]

Maybe "being sucked into a train" is a myth, but why can't somebody ask a question about it?

After all, there is even a show on TV called MYTHbusters!

(And many people watch it too!)

We all could worry about being killed by the winds of a hurricane. However, most deaths from a hurricane do not come from the wind or flying objects, Most deaths occur from flooding, sometimes hundreds of miles inland!

I myself welcome all questions that people want to ask. If it doesn't interest me, or if I think it's "stupid and shouldn't be asked", I don't answer it - unlike a certain person!

I think the person with the largest number of posts in this thread is the same one questioning "Why should this be asked"! So why post?