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Why are engines being towed idling?

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Why are engines being towed idling?
Posted by Anonymous on Sunday, April 1, 2007 1:07 AM
I have noticed when a large number of engines (say a dozen) are being moved as part of a larger train they are usually on and idling. Other times they appear to be on line and pulling. This doesn't seem to make obvious sense as their additional power is certainly not needed, nor can it even be fully used.  Why burn that extra fuel just to be towed along?  Thanks.
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Posted by Namerifrats on Sunday, April 1, 2007 2:28 AM
Same reason we leave them idling when standing. When it's cold it keeps the water plugs from dumping the water in the engine. Also helps to have the extra air compressors running to charge the trainline quicker after stopping.
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Posted by csxengineer98 on Sunday, April 1, 2007 5:11 AM
depending on the time of year.. they are left running but not online to keep them from freezing up..in warm and cold weather...the batteries might be low and if the unit is shut down..it might not be able to be restarted without haveing to jump start it... and also there are restrictions as part of the opporating rules that state now many axles you may have in power/dynmaic brake... to comply with the rules some of the engins in a large consist cant be online and have to be isolated... also keep in mind that just becouse a locomotive has 6 axles under it donst mean it is a 6 axle locomotive as far as figering out the number of axles alowed on line.... each class of locomotive is given an axle value based on the amout of tractive effort it can generate.. for example a AC locomotive such as a sd-70mac might only have 6 axles under it but if memory serves me correct..on csx they are valued as haveing 9 axles... so when an engineer is figering out how many axles he can have online..he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

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Posted by Anonymous on Sunday, April 1, 2007 11:24 AM

Thanks guys. Makes more sense now.

 If you do have to jump start due to a low battery is it a big deal with the AAA (Tongue [:P]) or can you just connect to another engine through the regular cables and do a normal start?

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Posted by adrianspeeder on Sunday, April 1, 2007 12:36 PM

They are beefy cables.  I think Ed has a good story bout that...

 

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Posted by csxengineer98 on Sunday, April 1, 2007 4:14 PM
 dalien wrote:

Thanks guys. Makes more sense now.

 If you do have to jump start due to a low battery is it a big deal with the AAA (Tongue [:P]) or can you just connect to another engine through the regular cables and do a normal start?

there are jumper cables that are just like the kind  you use to jump you car..but alot longer and the cables are thicker..  you put the aligator clamps on the battery knife switch of one unit that is good..the the knife switch of a unit that needs the jump...then go fire that puppy up

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Posted by Anonymous on Sunday, April 1, 2007 4:22 PM
 csxengineer98 wrote:
 dalien wrote:

Thanks guys. Makes more sense now.

 If you do have to jump start due to a low battery is it a big deal with the AAA (Tongue [:P]) or can you just connect to another engine through the regular cables and do a normal start?

there are jumper cables that are just like the kind  you use to jump you car..but alot longer and the cables are thicker..  you put the aligator clamps on the battery knife switch of one unit that is good..the the knife switch of a unit that needs the jump...then go fire that puppy up

csx engineer 

 

That's just like we did it down on the farm.Approve [^]  That cable set must weigh a bunch to drag around.

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Posted by Anonymous on Sunday, April 1, 2007 4:39 PM

 csxengineer98 wrote:
he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

csx engineer
Can a cluster of dead engines (not running) be towed OK on a warm day as part of a regular consist, just other boxcars, or does their great weight require the additional braking air etc which their running engines can provide? Confused [%-)] 

(The reason I ask is that I've seen heavy old antique steam engines moved slowly, but placed between two big diesel engines and some extra coal cars just for the extra braking control they provide.)

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Posted by csxengineer98 on Sunday, April 1, 2007 8:29 PM
 dalien wrote:

 csxengineer98 wrote:
he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

csx engineer
Can a cluster of dead engines (not running) be towed OK on a warm day as part of a regular consist, just other boxcars, or does their great weight require the additional braking air etc which their running engines can provide? Confused [%-)] 

(The reason I ask is that I've seen heavy old antique steam engines moved slowly, but placed between two big diesel engines and some extra coal cars just for the extra braking control they provide.)

i should have clairifed that axle value thing a little... so i will do that now.. if the unit is dead..as in dead in tow and cant be started..or is shoped and cant be used for power..the unit dosnt count for firgering axle vaules numbers..... only units that have the potental to be used as power are figreded into this... 

now to awnser your question... if they are dead and cant be used for power becouse of being shops or cant be started..or if the weather is warm and the unit isnt needed for power to pull the train and is shut down to save fuel... it is considered as far as train handeling goes just another car in the train... and depending on how the air brakes are set up on each unit being towed..they will as far as brakeing goes..respond as a car..or as part of the engin consist...

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Posted by Anonymous on Sunday, April 1, 2007 10:37 PM

...depending on how the air brakes are set up on each unit being towed..they will as far as brakeing goes..respond as a car..or as part of the engin consist...

Thank you. Very helpful posts.

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Posted by Anonymous on Monday, April 2, 2007 7:48 PM
If you lose power on an active unit while enroute will you also lose the braking power (both dynamic and static) from that unit? Cowboy [C):-)]
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Posted by csxengineer98 on Monday, April 2, 2007 8:23 PM

 dalien wrote:
If you lose power on an active unit while enroute will you also lose the braking power (both dynamic and static) from that unit? Cowboy [C):-)]
dynmaic yes... air no...

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Posted by Anonymous on Tuesday, April 3, 2007 9:37 AM
 csxengineer98 wrote:

 dalien wrote:
If you lose power on an active unit while enroute will you also lose the braking power (both dynamic and static) from that unit? Cowboy [C):-)]
dynmaic yes... air no...

csx engineer 

  That's very interesting csxengineer98. Wink [;)] As an Electrical Engineering exercise it would seem to be a simple matter of rewiring (by relays, or whatever) to maintain the dynamic braking asset in a towed unit. Hmmm...
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Posted by Randy Stahl on Tuesday, April 3, 2007 3:40 PM
 dalien wrote:
 csxengineer98 wrote:

 dalien wrote:
If you lose power on an active unit while enroute will you also lose the braking power (both dynamic and static) from that unit? Cowboy [C):-)]
dynmaic yes... air no...

csx engineer 

  That's very interesting csxengineer98. Wink [;)] As an Electrical Engineering exercise it would seem to be a simple matter of rewiring (by relays, or whatever) to maintain the dynamic braking asset in a towed unit. Hmmm...

It's been done , field loop dynamics worked on trailing units regardless if they were running or not . Problem was the connectors blowing to bits between the power and contactors getting hung up .

 

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Posted by dima on Tuesday, April 3, 2007 5:05 PM

 csxengineer98 wrote:
depending on the time of year.. they are left running but not online to keep them from freezing up..in warm and cold weather...the batteries might be low and if the unit is shut down..it might not be able to be restarted without haveing to jump start it... and also there are restrictions as part of the opporating rules that state now many axles you may have in power/dynmaic brake... to comply with the rules some of the engins in a large consist cant be online and have to be isolated... also keep in mind that just becouse a locomotive has 6 axles under it donst mean it is a 6 axle locomotive as far as figering out the number of axles alowed on line.... each class of locomotive is given an axle value based on the amout of tractive effort it can generate.. for example a AC locomotive such as a sd-70mac might only have 6 axles under it but if memory serves me correct..on csx they are valued as haveing 9 axles... so when an engineer is figering out how many axles he can have online..he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

csx engineer

Can you clarify, what's the reason axles are being counted. I understand there may be a need to limit total pulling power for a train (to avoid broken knucke) but why base it in axle count especially this weird thing where 6-axle is considered 9-axle? Axel count on a locomotive does not indicate its pulling power.

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Posted by Randy Stahl on Tuesday, April 3, 2007 6:01 PM
 dima wrote:

 csxengineer98 wrote:
depending on the time of year.. they are left running but not online to keep them from freezing up..in warm and cold weather...the batteries might be low and if the unit is shut down..it might not be able to be restarted without haveing to jump start it... and also there are restrictions as part of the opporating rules that state now many axles you may have in power/dynmaic brake... to comply with the rules some of the engins in a large consist cant be online and have to be isolated... also keep in mind that just becouse a locomotive has 6 axles under it donst mean it is a 6 axle locomotive as far as figering out the number of axles alowed on line.... each class of locomotive is given an axle value based on the amout of tractive effort it can generate.. for example a AC locomotive such as a sd-70mac might only have 6 axles under it but if memory serves me correct..on csx they are valued as haveing 9 axles... so when an engineer is figering out how many axles he can have online..he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

csx engineer

Can you clarify, what's the reason axles are being counted. I understand there may be a need to limit total pulling power for a train (to avoid broken knucke) but why base it in axle count especially this weird thing where 6-axle is considered 9-axle? Axel count on a locomotive does not indicate its pulling power.

On our railroad braking  effort is limited to 200.000 lbs. On older conventional locomotives, each axle can produce 10.000 lbs of effort. A six axle SD40-2 or a C-30-7 can produce 60.000 lbs of braking effort.

The next step was the higher capacity dynamics like the GP50 and the dash 8 locomotives. These engines can produce 15,000 lbs per axle . A GP50 can produce the same effort as an SD40 so it counts as a six axle locomotive. The AC locomotives have even higher braking effort and I think that each AC motor is good for 20,000 lbs of effort , I would count that as two conventional locomotives or 12 axles.

It's easier to remember an axle count than to do the calculations based on traction motor output.

So as an exercise , here are your parameters. Your railroad has a head end limit for dynamic brakes of 240,000 lbs. Your the engineer and your consist is this: SD40-2,AC4400, AC4400,SD60, SD60,B40-8. Some of your locomotives are going to have to have the dynamic brakes cutout. Which ones?

Dynamics are limited because too much buff force can wreck the railroad.

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Posted by csxengineer98 on Tuesday, April 3, 2007 6:08 PM
 dima wrote:

 csxengineer98 wrote:
depending on the time of year.. they are left running but not online to keep them from freezing up..in warm and cold weather...the batteries might be low and if the unit is shut down..it might not be able to be restarted without haveing to jump start it... and also there are restrictions as part of the opporating rules that state now many axles you may have in power/dynmaic brake... to comply with the rules some of the engins in a large consist cant be online and have to be isolated... also keep in mind that just becouse a locomotive has 6 axles under it donst mean it is a 6 axle locomotive as far as figering out the number of axles alowed on line.... each class of locomotive is given an axle value based on the amout of tractive effort it can generate.. for example a AC locomotive such as a sd-70mac might only have 6 axles under it but if memory serves me correct..on csx they are valued as haveing 9 axles... so when an engineer is figering out how many axles he can have online..he has to look at the whole consist and total up the axle vaules for all the engines.. and if the total number is more then he is alowed..he has to isolate some units..

csx engineer

Can you clarify, what's the reason axles are being counted. I understand there may be a need to limit total pulling power for a train (to avoid broken knucke) but why base it in axle count especially this weird thing where 6-axle is considered 9-axle? Axel count on a locomotive does not indicate its pulling power.

the reason for limiting axles in power and dymanic brake is so you dont put to much buff or draft forces on the draft gear and knuckes...to many axles on line when starting out can either rip the drawhead or knuckel off the car..or worse yet string line the train and derail it..and if to many axles are online for dynmaic brakeing..you can cuase to much buff forces on the cars and buckle the train and derail....

also it is based on axle counts becouse each class of locomotive generates differnt levels of tractive efforts... the 9 axle worth of power value on a 6 axle engin is becouse that unit as far as the amount of pulling power it can generat is equal to a locomotive haveing 9 axles...

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Posted by Rodney Beck on Wednesday, April 4, 2007 11:38 AM

Hello everyone on BNSF according to the air brake train handleing rule book on any train I can have up to 42 rated powered axles, on a total intermodal train I can have 48 rated powered axles. The dynamic requirements are no more than 28 rated dynamic brake axles due to high buff force that can be created when the train gets around 10mph. When I figure how many dynamic brake axles I will use I take the tonnage of the train and divide by the axles of dynamic I have for my use, on the newer and some older units I can cut out the dynamics on that unit not to exceede 400 tons per dynamic brake axle.

 

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Posted by wabash1 on Wednesday, April 4, 2007 12:06 PM
 Rodney Beck wrote:

Hello everyone on BNSF according to the air brake train handleing rule book on any train I can have up to 42 rated powered axles, on a total intermodal train I can have 48 rated powered axles. The dynamic requirements are no more than 28 rated dynamic brake axles due to high buff force that can be created when the train gets around 10mph. When I figure how many dynamic brake axles I will use I take the tonnage of the train and divide by the axles of dynamic I have for my use, on the newer and some older units I can cut out the dynamics on that unit not to exceede 400 tons per dynamic brake axle.

 

Rodney 

 

Rodney

   Not wanting to question your word, But in the way you state this is a little high for powered axels. Now I am allowed 24 powered axels on line ( 32 if solid bulk train) and for the sake of doing alot of math we have a rule of no more than 18 axels of dynamic. the way I see it you are allowed 6 dash-9 on line  ( 8 x 6 = 48  and  8x5 = 40 ) For the ones not knowing how we figure powered axels the NS does it like this. A dash 9 axel is equal to a 1 1/3 power  so a 6axel high adheshion unit ( these are sd 50,60,70,80,90 ge dash 8,9 the ac units and so on.) and then add the 1/3 up, so you have 3 axel truck in front and 3 axel in back. front truck 3 +1/3 + 1/3 + 1/3 = 3/3 or to me 1 total of 4 same in rear so 4+4=8  this is how you get 8 axels of power out of 6 axels. and then  for the ac traction motor is 9 or 1 1/2 axels  or 4 1/2 per truck and take that and the rear 4 1/2 + 4 1/2 = 9. now back to rodney how is yours figured so i can be on the same page ?

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Posted by Limitedclear on Wednesday, April 4, 2007 1:04 PM

Colleagues -

Actually, the reason for the axle limitation is not limited to in train forces, although that is certainly a very valid reason. I can remember well when the NS adopted the axle limitation rule. At the time we had an incident where a train was being shoved on to a siding through a control point. There were six large units on the head end of the 130 car mixed freight train (GE Dash9s that rate as 9 axles) and all were on line. As they shoved through the wye at the control point the forces exerted on the rail caused the track structure to fail in a spectacular way resulting in several cars leaving the track in a pile.

The next day we had a new order limiting the number of axles online and instructing how to account for the axle counts.

Oh, and on a sad note, although there were no injuries on the scene, a young contractor lost his life while scrapping one of the boxcars involved a few days later when he apparently cut the wrong part and a boxcar door fell free directly onto the contractor killing him instantly.

LC 

 

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Posted by Rodney Beck on Wednesday, April 4, 2007 2:35 PM

Wabash I am using air brake train handling rules #3 dated July 13 2003 and revised April 03 2003 here are the rule # 102.11 powered axle limitation page 32, 103.3.1 dymanic brake limitations. where I find the rated powered and dynamic brake axle for BNSF is in the SSI that lists the modle of the engines, i.e. a ge es44dc has 8 rated powered and dynamic brake axles, a sd75m has 7 rated powered axles and 9 rated dynamic brake axles.

 

Rodney

 

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Posted by csxengineer98 on Wednesday, April 4, 2007 3:52 PM
 Limitedclear wrote:

Colleagues -

Actually, the reason for the axle limitation is not limited to in train forces, although that is certainly a very valid reason. I can remember well when the NS adopted the axle limitation rule. At the time we had an incident where a train was being shoved on to a siding through a control point. There were six large units on the head end of the 130 car mixed freight train (GE Dash9s that rate as 9 axles) and all were on line. As they shoved through the wye at the control point the forces exerted on the rail caused the track structure to fail in a spectacular way resulting in several cars leaving the track in a pile.

The next day we had a new order limiting the number of axles online and instructing how to account for the axle counts.

Oh, and on a sad note, although there were no injuries on the scene, a young contractor lost his life while scrapping one of the boxcars involved a few days later when he apparently cut the wrong part and a boxcar door fell free directly onto the contractor killing him instantly.

LC 

 

that one of the many reasons why the came up with axle limiting rules... but from what you said sounds to me like that incident was the result of buff forces on the train.. causeing it to roll the rail over.. the forces dont just affect the cars as you know..but the track also..and will fail at the weakest link in the chain and in your case it was the track...

there is also limits on the number of axles you can have online for shoving cars too.. not just pulling trains..to prevent the build up of excessive buff forces and haveing that happen... 

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Posted by edblysard on Wednesday, April 4, 2007 4:25 PM

Had our own little example of buff forces at work...

Monday, one of our industry jobs returns to North yard with their train...plan was to drag through the yard, get head room, then shove back into our storage yard...about a mile shove, no big deal.

Conductor is about a year, maybe a year and a half on the job.

Engineer is newly promoted two months ago.

They had assembled the train out in the "country"on the instructions of one of our trainmasters...

89 cars, 84 of them full of stuff that ends in "ine"...lots of methyl ethyl awful stuff...with two empty tallow tank cars head out next to the motor, followed by two 89' TTX flats with the long, floppy drawbars and last cover car was a empty mill gon...the only cars out there the trainmaster could figure out were cover cars.(the train had 15 class 3  combustibles in the middle, no restrictions on placement in the train, but trainmasters know best)

They got the head room, the conductor gets on the rear car, and away they go...the engineer has a light reduction on the train to keep the slack run in so the conductor doesn't get beat up too bad, and he knows they will be stopping for bad rails along the way.

Lots of curves leading to the storage yard...and the motor happened to be stopped in the middle of one.

Sure enough, they go about ten cars into the shove, the conductor radios "two more to a bad one" and the hogger draws a little more air off...surprise!

The first flat tried to go east, the second one went west, the gon went south, just did it sideways.

One of the empty tallow tanks rolled over out of sympathy, I guess, or the flat car took it along for the ride.

 

Imagine, shoving 84 loads with 5 empties on the head end through curves, and the silly things have the nerve to derail when the floppy drawbars got in a bind in the curve!

The conductor had no clue why, the engineer figured it out, the trainmaster already knows, and is desperately trying to either say it was track failure or the engineer shoved to hard!

Well, of course the track failed, it normally does when you exceed it limits of common sense...and the hogger did nothing wrong, he was following our train handling rules about shoving with someone on the point, keep the slack bunched up to protect the man riding.

 

Put the entire end of North yard out of service most of the day, because a trainmaster doesn't understand the difference between hazardous material non hazardous material and never read the placement in train chart...just grabbed the first 5 cover cars he could find and used them, or never though about the forces in play when you shove a train instead of dragging it.

 

What you had was 2 Dash 9s, (8800 hp) pushing against dead weight in a curve, and as CSXengineer pointed out, the weakest link failed.

23 17 46 11

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Posted by MP173 on Wednesday, April 4, 2007 4:56 PM

Ok Ed...help me out here...remember I am not a railroader.

Did the train derail because you had power pushing on empties (5) which then had to shove the loads and it was on a curve?  What exactly caused the derailment?  The "sandwitch" effect (sorry for the terminology) of the empties between power and weight?

Had the train not been on a curve, would it not derailed (in your opinion)?

Where should the empties been placed?

thanks,

ed

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Posted by Randy Stahl on Wednesday, April 4, 2007 5:23 PM
Ed , did the same thing in Janesville Wi, had 5 F units shoving up hill , around a curve with 106 grain loads and 5 MT boxcars head pin .. ever seen a boxcar fly ?
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Posted by Bob-Fryml on Thursday, April 5, 2007 4:34 PM

Often the soda ash empties that run from North Platte to southwestern Wyoming will move with six C44's on the point with as many as 165 covered hoppers in tow.  The first two units in the locomotive consist are under power with the last four "off line," i.e., not loading.  U.P. follows this practice in the interest of fuel economy.

During the warmer weather months, the off line power is usually shut down; but, in the colder seasons of the year it's kept running to prevent the radiator water from freezing. 

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Posted by zapp on Thursday, April 5, 2007 4:48 PM

There are times when i get a manifest train with either yard power or local power on it. It either has to go be serviced, inspected or both. A southbound will pick up the local's current power then a northbound will set out either the serviced power or replacement power for them.

For example, we have a local that works at Roanoke, Texas ( about 25 miles north of tower 55) they switch industries at Roanoke, go to Denton make their switches, then proceed back to Roanoke where they setout cars bound for Ft Worth. If their power needs something, they leave their power on that pick up. A southbound manifest (usually the MDNFW) will pick everything up and set it out at Centinnial Yard. Then everything reverses itself going north.    

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Posted by csxengineer98 on Friday, April 6, 2007 5:24 PM

 Randy Stahl wrote:
Ed , did the same thing in Janesville Wi, had 5 F units shoving up hill , around a curve with 106 grain loads and 5 MT boxcars head pin .. ever seen a boxcar fly ?
wow.. must have been a sight to see..lol... did you come a little to heavy and hot on the throttle?

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Posted by Randy Stahl on Friday, April 6, 2007 5:45 PM
 csxengineer98 wrote:

 Randy Stahl wrote:
Ed , did the same thing in Janesville Wi, had 5 F units shoving up hill , around a curve with 106 grain loads and 5 MT boxcars head pin .. ever seen a boxcar fly ?
wow.. must have been a sight to see..lol... did you come a little to heavy and hot on the throttle?

csx engineer 

Got a wheelslip and all hell cut loose !!!!!

 

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Posted by cordon on Friday, April 6, 2007 6:17 PM

Re: Had our own litle example of buff forces at work.

Somewhere in training  both the conductor and the engineer should have been warned about MTs at the head of a train.  It can happen when pulling, too.

 

Smile [:)]

 

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