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Dynamic vs Air Brakes....When do you use which?

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Posted by BigJim on Wednesday, April 23, 2008 7:30 AM

you know as well as i do that the carriers want you to learn how to strech break too..

Do I?
Well I would hope that there is someone, somewhere in the system that knows what they are doing, however, it doesn't seem to trickle down in a heavy enough stream. It's amazing how brainwashed some of these low level officials turn out to be.  

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Posted by csxengineer98 on Wednesday, April 23, 2008 4:23 AM
 BigJim wrote:

ok.... under the rules of my road..they want you to use dynmaic and throttle modulation to controll train speed as opposed to strech breaking (useing the air)when condistions alow it... 

So what happens when the engineers start believing this stuff and never learn to stretch brake?
They don't know what to do when the dynamic brake fails and ultimately wind up delaying the entire district (in the very least).

We've been taught the same thing.
Some have took it on their own to learn how to be the best that they can be and that includes knowing how to use the air.

In the "Something Funny Happened On The Way To The Forum" category;
Way back when I went to engine school, we actually trained on a real train on real track, none of this simulator crap! AND, we were first taught to stretch brake! Fast forward to graduation day and along comes "Mean Gene" and the first words out of his mouth were..."We're not going to have any air brake artists out there...blah...blah...blah." Now, I'm sitting back there thinking this guy is an idiot. Why in the world would a class one RR want to put SAFETY in jeopardy by not having the best trained personel possible?

Remember TOP GUN?
"Train Like You Fight...Fight Like You Train"
Well piglets, it's the same darn thing, with the exception being these hogs are stuck to the rails.

you know as well as i do that the carriers want you to learn how to strech break too.. not ever engin is going to have working dynamic or you might have a leader that dosnt have DB and you know as well as i do that if you dont have the control handel on the control stand (which i have run across once in a great while) any other unit with it isnt going to work becouse you dont have the ability to use it...or as you pointed out that if the DB should fail.. that is why i said when conditions permit they want you to use DB and throttle modulation as opposed to strech breaking

csx engineer 

"I AM the higher source" Keep the wheels on steel
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Posted by wsherrick on Wednesday, April 23, 2008 2:20 AM

 If I was in that situation I probably would've done the same thing. So far I have been very lucky and never have pulled a knuckle.  Now that I've said that, I'll probably do it tomorrow.

Feel free to tell all of the stories you want to.  I can tell about when I was a conductor and my engineer didn't know how to use the automatic EVER.  When switching long cuts of cars he would always use the independent to try and stop everything.  If I wasn't ready for it, he would yank my teeth out.  When I was two or three cars away from clearing a switch I would tell him one car so by the time he got the train stopped, it would generally be close to the right place.

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Posted by UPRR engineer on Wednesday, April 23, 2008 1:32 AM

I hope your kidding.... if not why would i not have the drivers all the way on?? I was trying to stop.

Theres one example, if your going down hill in dynamics and they kick out (or ya get off them), and you grab full service like i did, bailing off the locomotive brakes might get ya a knuckle right behind the power. The slack as the power rolls away from the train... aint good.

I gotta a couple more good stories about guys that dont know the air real well. 

 

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Posted by wsherrick on Wednesday, April 23, 2008 1:07 AM
 UPRR engineer wrote:
 Sunnyland wrote:

I'd be interested in hearing any stories you have to share. 

I've been a train twice where the dynamic brakes kicked out at the last second. First time i was new to the UP and on the brakemens board, second time as the engineer. Both times near Green River, one time from each direction.

Think id been with the UP for about 6 months, we were dogcatching west bound trains and bringing them into town. We were on a loaded auto rack and remember we had a one of those CNW AC motors. We were coming up to a red A block outside of town, had good lights for quite a ways until we got close to town. Ya have to get pretty close to the block in order to see the lights. So were putting along for the last 1/2 mile about 10mph, a slight down hill grade. 1/4 mile to the stop, little more dynamic... little more.... getting a feel for it. No air set yet, getting after it a little harder now.... he just about had it stopped then BLAM..... dynamics kicked out, all those long drawbars cars shoved us threw the block.

This time i was coming down the hill into town with good lights all the way in, big old double stack, power was a pack of those new EMD's right after they came out, i was told to stop the headend out front to change crews. Its fun to come in hot and see if you can put the steps on the walk way. Came around the last curve with all the motors screaming in dynamic, feeling for when i thought i should grab the air..then..BLAM lost them all. I wasnt looking at a red one, the worst i had,.... going past the walkway in full service,.....with the brakes on those new motors squeeling,.... and the outbound crew wondering what i was doing.

 

 

 

That's a good story.  Did you remember to bail off the independant ????

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Posted by UPRR engineer on Wednesday, April 23, 2008 12:06 AM
 Sunnyland wrote:

I'd be interested in hearing any stories you have to share. 

I've been a train twice where the dynamic brakes kicked out at the last second. First time i was new to the UP and on the brakemens board, second time as the engineer. Both times near Green River, one time from each direction.

Think id been with the UP for about 6 months, we were dogcatching west bound trains and bringing them into town. We were on a loaded auto rack and remember we had a one of those CNW AC motors. We were coming up to a red A block outside of town, had good lights for quite a ways until we got close to town. Ya have to get pretty close to the block in order to see the lights. So were putting along for the last 1/2 mile about 10mph, a slight down hill grade. 1/4 mile to the stop, little more dynamic... little more.... getting a feel for it. No air set yet, getting after it a little harder now.... he just about had it stopped then BLAM..... dynamics kicked out, all those long drawbars cars shoved us threw the block.

This time i was coming down the hill into town with good lights all the way in, big old double stack, power was a pack of those new EMD's right after they came out, i was told to stop the headend out front to change crews. Its fun to come in hot and see if you can put the steps on the walk way. Came around the last curve with all the motors screaming in dynamic, feeling for when i thought i should grab the air..then..BLAM lost them all. I wasnt looking at a red one, the worst i had,.... going past the walkway in full service,.....with the brakes on those new motors squeeling,.... and the outbound crew wondering what i was doing.

 

 

 

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Posted by BigJim on Tuesday, April 22, 2008 6:58 PM

ok.... under the rules of my road..they want you to use dynmaic and throttle modulation to controll train speed as opposed to strech breaking (useing the air)when condistions alow it... 

So what happens when the engineers start believing this stuff and never learn to stretch brake?
They don't know what to do when the dynamic brake fails and ultimately wind up delaying the entire district (in the very least).

We've been taught the same thing.
Some have took it on their own to learn how to be the best that they can be and that includes knowing how to use the air.

In the "Something Funny Happened On The Way To The Forum" category;
Way back when I went to engine school, we actually trained on a real train on real track, none of this simulator crap! AND, we were first taught to stretch brake! Fast forward to graduation day and along comes "Mean Gene" and the first words out of his mouth were..."We're not going to have any air brake artists out there...blah...blah...blah." Now, I'm sitting back there thinking this guy is an idiot. Why in the world would a class one RR want to put SAFETY in jeopardy by not having the best trained personel possible?

Remember TOP GUN?
"Train Like You Fight...Fight Like You Train"
Well piglets, it's the same darn thing, with the exception being these hogs are stuck to the rails.

.

  • Member since
    March 2008
  • 146 posts
Posted by wsherrick on Tuesday, April 22, 2008 5:09 PM
 csxengineer98 wrote:

ok.... under the rules of my road..they want you to use dynmaic and throttle modulation to controll train speed as opposed to strech breaking (useing the air)when condistions alow it...  the first 2 the engineer has to know his territory to know when to do what and how much to notch off or how much dynamic to use... when i was in the seat and the division i ran over..there where lots of places where all it would take to drop the train speed down for a speed zone change was just notching back off the throttle a mile or 2 befor the start of the zone and the train will just settle right down to the speed that i needed it to be at at the speed limit sign.. a populer misconseption about dynamic is that the use of it can cause a wreck.. the proper term should be..MIS-use of it will cause a wreck.. the thing that i learned from some old heads when i was training was that you never do anything sudden and fast in normal day to day running..(emergancy situations are another story)... you can slow a train down to a crawl just by notching off..letting the trains slack settle out for 10 seconds (which is what they say in the rules to do anyways) and slowing gaithering up the slack.. once you get the slack bunched..you can pour on the dynamic.. slack changes is what cuases problems and wrecks.. to much of one thing or another to fast while the train isnt bunched or streched is where problems happen.. i use to be take 18000 tons of coal and drop it to almost a stop in a mile from beeboping along at a 25mph clip.. with just dynmaic.. and i never wrecked one yet running the train the way i did it..

also as someone mentioned above..every engineer is a legond in his own mind.. they pay good engineers just as much as bad ones.. the true test to who are good engineers and who arent are the ones that when your sitting around the office with other crews and listen to who they are talking good or bad about.. railroaders are worse then women when it comes to bad talking about fellow coworkers and will talk trash on anyones running style from how much they blow the horn to how bad they get run-ins and runouts of slack... but to find that type of thing out you have to be employeed by the company or be around a few railroaders that might be out as a small group at a bar and you hear them talking shop... 

csx engineer 

I can tell you've really worked for a railroad.  You are 199% right about the back stabbing that goes on.  After my shift is over I go home. 

I feel very fortunate to have learned how to run on steam with No. 6 brakes and and plenty of diesels with every brake type in between.  I work for a shortline company that operates several different lines, some with pretty steep grades with engines that have 14 or 24 brakes without pressure maintaining and NO dynamics.  I learned from the last of the old steam men and they were hard but good teachers.  I had one old engineer hold the independant brake in release and wouldn't let me cheat by using it.  The only time I got to handle it is when I had to bail off.  I thought I would never get the hang of it before the fear of piling the train up at the bottom of the hill would wear off. But eventually I did.  I learned how to feel the train by the seat of your pants and if a brake application would take or not or if I made too much of a reduction.

I agree in the best way to wreck a train is to not have an understanding about the nature of slack.  One method that I use to control train speed and conserve my main reservoir is to allow the curves to slow the train down.  I will release the brakes just before I come into a curve and the curve generally will hold the train below the allowed speed and it gives time for the brakes to recharge.  The longer/heavier the train the more I pinch it down before releasing.  In this manner the slack eases in and out in a slow, safe manner without the dreaded accordian effect.  Of course with the old fashioned way of doing things one never starts without a leakage test and a running brake test to see how the train feels.  I never skip either of these tests.  To do so could mean real trouble once we crest the grade and start down.

 

 

 

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Posted by BaltACD on Tuesday, April 22, 2008 5:02 PM
 Sunnyland wrote:

I don't know much about the mechanics, but I do know about railroaders from my Dad. He worked in Frisco RR yard office and he heard lots of stories about right way, wrong way, etc.

 I don't know what a dynamic brake is, only one I ever knew about was air brakes. Must be something newer from the way everyone talks.  I know about slack, used to hear that in the yards when Dad and I would hang out watching trains being put together. 

Dynamic Braking has been around since the orignal EMD FT demonstrator locomotives of 1939.  In it's simplest form it is nothing more than electrically changing the Traction motors into generators.  The train momentum supplys the 'power' to turn the traction motor/generator....the more current the engineer demands from the traction motor/generator the more retardation is generated on the train.  As generators the traction motors generate current that is disapated into heat on the dynamic brake grids and thus create braking power on the train.

Never too old to have a happy childhood!

              

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Posted by Sunnyland on Tuesday, April 22, 2008 4:52 PM

I'd be interested in hearing any stories you have to share. 

I've heard a few from my Dad, but only from the yards, not over the road.  He worked in the yards as a clerk and then moved up into the yard office.  Railroading can be a very dangerous profession, especially in the old days before safety rules.  Mom's father worked for Frisco also as conductor and he had the usual missing index finger from the old link and pin coupler.

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Posted by Sunnyland on Tuesday, April 22, 2008 4:44 PM

I don't know much about the mechanics, but I do know about railroaders from my Dad. He worked in Frisco RR yard office and he heard lots of stories about right way, wrong way, etc.

 I don't know what a dynamic brake is, only one I ever knew about was air brakes. Must be something newer from the way everyone talks.  I know about slack, used to hear that in the yards when Dad and I would hang out watching trains being put together. 

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Posted by csxengineer98 on Tuesday, April 22, 2008 4:31 PM

ok.... under the rules of my road..they want you to use dynmaic and throttle modulation to controll train speed as opposed to strech breaking (useing the air)when condistions alow it...  the first 2 the engineer has to know his territory to know when to do what and how much to notch off or how much dynamic to use... when i was in the seat and the division i ran over..there where lots of places where all it would take to drop the train speed down for a speed zone change was just notching back off the throttle a mile or 2 befor the start of the zone and the train will just settle right down to the speed that i needed it to be at at the speed limit sign.. a populer misconseption about dynamic is that the use of it can cause a wreck.. the proper term should be..MIS-use of it will cause a wreck.. the thing that i learned from some old heads when i was training was that you never do anything sudden and fast in normal day to day running..(emergancy situations are another story)... you can slow a train down to a crawl just by notching off..letting the trains slack settle out for 10 seconds (which is what they say in the rules to do anyways) and slowing gaithering up the slack.. once you get the slack bunched..you can pour on the dynamic.. slack changes is what cuases problems and wrecks.. to much of one thing or another to fast while the train isnt bunched or streched is where problems happen.. i use to be take 18000 tons of coal and drop it to almost a stop in a mile from beeboping along at a 25mph clip.. with just dynmaic.. and i never wrecked one yet running the train the way i did it..

also as someone mentioned above..every engineer is a legond in his own mind.. they pay good engineers just as much as bad ones.. the true test to who are good engineers and who arent are the ones that when your sitting around the office with other crews and listen to who they are talking good or bad about.. railroaders are worse then women when it comes to bad talking about fellow coworkers and will talk trash on anyones running style from how much they blow the horn to how bad they get run-ins and runouts of slack... but to find that type of thing out you have to be employeed by the company or be around a few railroaders that might be out as a small group at a bar and you hear them talking shop... 

csx engineer 

"I AM the higher source" Keep the wheels on steel
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Posted by UPRR engineer on Tuesday, April 22, 2008 3:04 PM

No.... just because a guys has the title of Engineer doesnt mean they know how to run a train really well. "A Good Hoghead" thats what you call a good engineer. Theres alot of people out there that just get by. Guess it just boils down to knowing what you can do with a train.

Old saying around here about engineers, theres the good ones... and the great. It's pretty hard to find a guy that will admit they suck. The times ive ripped on guys for running like crap, you can almost see the tears starting to fall. Out of all the guys ive saw, id only call 10% of them "good hogs". Thats my take on it. Things are changing, saving fuel is whats most important.

If they could teach a monkey to run a train, they would be on there insted of me. Does that tell you the kinda guys i work around??

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Posted by BaltACD on Tuesday, April 22, 2008 2:42 PM

Virtually any idiot can open up the throttle....

An Engineer knows how to brake the train and get it over the road.

Never too old to have a happy childhood!

              

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Posted by UPRR engineer on Tuesday, April 22, 2008 2:13 PM
Its best to use a little of both, using just alot of dynamic's burns quite a bit of fuel. The best way to run a train is to wait as long as you can and let the slack adjust on its own before doing any kind of braking. One problem some of those dynamic brake loving hogs can have, them kicking out at the last minute, then its panic time. The other problem is not knowing what you "gotta hold of", waiting till its time to stop aint the best time to see how well the brakes are going to work. It takes quite a bit of skill to learn how to use the air brakes well. Theres alot of guys out there who dont. I've got quite a few stories if anyones interested.
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Posted by Anonymous on Sunday, April 20, 2008 1:53 PM

 wsherrick wrote:
I learned how to run engines with a 6 brake.  One the railroad I work for we still have engines with 6, 14 and 24 brakes and no dynamic braking.  To me a modern 26 brake is child's play.  It's self lapping and has pressure maintaining.  The older systems of brakes require a lot of experience and you really have to know the physical characteristics of your run.  It's all in your hands with those babies.

I worked for a shortline with the majority of the brakes being 24 with no dynamics. Most of the engineers I worked with despised them. The guys who hire on with the class 1's nowadays only see these things in history books.

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Posted by Gary UK on Sunday, April 20, 2008 7:40 AM
 jeffhergert wrote:

Dynamic braking is preferred. 

It's not unusual for me to go over my territory without touching the air, except when making a stop.  Even then slowing for the stop is usually done with dynamics.  Just depends on the kind of train you have and where you are at. 

Jeff 

Looks like i wasnt to far off the mark thenCool [8D]

Not bad considering that nothing here has dynamic brakes save for a few passenger trains that have regenerative braking aswel as friction brakes.

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Posted by wsherrick on Sunday, April 20, 2008 12:11 AM
I learned how to run engines with a 6 brake.  One the railroad I work for we still have engines with 6, 14 and 24 brakes and no dynamic braking.  To me a modern 26 brake is child's play.  It's self lapping and has pressure maintaining.  The older systems of brakes require a lot of experience and you really have to know the physical characteristics of your run.  It's all in your hands with those babies.
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Posted by jeffhergert on Friday, April 18, 2008 6:45 PM

Improper use of Dynamics can derail a train or cause a break in two. 

Dynamic braking is preferred.  When dynamics alone won't control speed then you use air.  If you need to slow down in a hurry, depending on train and circumstances, you will probably need to use air.

It's not unusual for me to go over my territory without touching the air, except when making a stop.  Even then slowing for the stop is usually done with dynamics.  Just depends on the kind of train you have and where you are at. 

Of course, if you don't have working dynamics, then you don't have a choice.

Jeff 

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Posted by Anonymous on Friday, April 18, 2008 6:04 PM
If you use the Dynamics only means that about 100 feet of slack could derail the train on a down grade
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Posted by Gary UK on Friday, April 18, 2008 3:36 PM

Let me first say that im no engineer but i'l take a guess here. I'd also like to know the propper reason!

My guess is that you can use both at the same time to save the friction brakes on units and train from burning up on long grades. Maybe the same reason why you could use dynamic brakes alone on a gentle downward grade to control the speed of the train instead of using friction brakes.

More units can be added to a heavy train just to provide added brake force rather than more pulling power. 

Over to the experts. 

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Dynamic vs Air Brakes....When do you use which?
Posted by Anonymous on Friday, April 18, 2008 11:04 AM
   As I understand it if you use the wrong braking system at the wrong time you have a mess on your hands

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