Dynamic brake & slack.

Nice writing.  You had me right in the cab with you.

The Texas bound BN coal trains rolled over challenging terrain most all the way...the hog-backed Fort Worth & Denver was basically built right on top of the ground.

Nice write-up, Wyhog.  I would personally have enjoyed working with you.

I have always advocated running the head-end and remote Distributed Power consists separately in anything other than really flat territory.

Rob Leese posted:

The Texas bound BN coal trains rolled over challenging terrain most all the way...the hog-backed Fort Worth & Denver was basically built right on top of the ground.

That's no exaggeration, Rob!  You and I have seen plenty of undulating territory, and have I can't imagine any humps and sags that are worse than the FW&D.  It's almost as though they could only afford two mules when they built the line.

I agree. Read like I was on board. You have a talent Wyhog.

645- Wyhog could describe it in better detail, but I know that at least some, possibly all, DPU systems allow for either "mirror" control- where the DPU does exactly what the head-end units do- or independent control.  The engineer can select either mode on his display in the cab.

Great replies and thank you.   ( There's an expression on the railway...You can lean something new every day)

At  the initial terminal where the train is made up. I wonder what special  instructions  are issued?  Does the Yard master just decide to stick a DPU at his discretion or are there rules?  EX . So many cars or tons from the leading units ?  Whether  empties or loads must come into the decision. Do crews have this info or special instructions?   Do we have any  Yardmasters on board? 

Gregg posted:

Great replies and thank you.   ( There's an expression on the railway...You can lean something new every day)

At  the initial terminal where the train is made up. I wonder what special  instructions  are issued?  Does the Yard master just decide to stick a DPU at his discretion or are there rules?  EX . So many cars or tons from the leading units ?  Whether  empties or loads must come into the decision. Do crews have this info or special instructions?   Do we have any  Yardmasters on board? 

 

 

Well, Yardmaster don't really have anything do with assigning motive power in the modern age. That is generally handled by the motive power desk, depending on the type and tonnage of the train. Unit coal trains historically had the DPU "helper" unit on the rear end, since mid-train DPUs are not allowed thru the coal loading silos nor the rotary dumpers at power plants. Grain movements might be set-up differently, and intermodal trains rarely have DPUs.

Hot Water posted:

Gregg posted:

Great replies and thank you.   ( There's an expression on the railway...You can lean something new every day)

At  the initial terminal where the train is made up. I wonder what special  instructions  are issued?  Does the Yard master just decide to stick a DPU at his discretion or are there rules?  EX . So many cars or tons from the leading units ?  Whether  empties or loads must come into the decision. Do crews have this info or special instructions?   Do we have any  Yardmasters on board? 

 

 

Well, Yardmaster don't really have anything do with assigning motive power in the modern age. That is generally handled by the motive power desk, depending on the type and tonnage of the train. Unit coal trains historically had the DPU "helper" unit on the rear end, since mid-train DPUs are not allowed thru the coal loading silos nor the rotary dumpers at power plants. Grain movements might be set-up differently, and intermodal trains rarely have DPUs.

The Yardmaster's crews make up the train. How do they know where & when  to put the DPUs...?? Or put a different way...Who makes this decision?   GYM ?  .  Every intermodal  here  (CP)  almost always has DPUs.

WYHOG,

Once the SD70MAC units began arriving, especially those equipped with the Harris Electronics radio control DPU operating system, and one of the Powder River Basin coal loading facilities deposited a small amount of fine Wyoming coal on top of the mid-train DPU, some of the coal obviously going into the radial dynamic brake grids. As soon as the crew went into dynamic brake, and those 54" diameter DB radial grids heated up, the spectacular 54" diameter flame that exited from the top of that unit, was truly a BIG EVENT. Naturally warranty was denied, and use of mid-train DPUs were discontinued, out of the entire Powder River area. 

I assume that the engineer can set the fence based on past experience for train make up and terrain or does he/she run it as set up (dictated) by a power desk or servicing personnel?

That's the question . At the Initial terminal who sets up the fence as you call it... I doubt very much it's the engineman, That would have been  already   set up before the crew reported for duty..

Gregg posted:

I assume that the engineer can set the fence based on past experience for train make up and terrain or does he/she run it as set up (dictated) by a power desk or servicing personnel?

That's the question . At the Initial terminal who sets up the fence as you call it... I doubt very much it's the engineman,

Then you would be incorrect.

That would have been  already   set up before the crew reported for duty..

No. The only thing that the initial terminal Mechanical Sept. personnel perform is the "link-up" between the lead unit, and the respective trailing DPUs. During the trip, the Engineer has the capability on his screen to "put up the fence" or not, depending on how he wants to control his train, based on his experience over his district.

When I was training Engineers and Road Forman of Engines on the DPU operations with BN/BNSF SD70MAC units, in the Powder River coal basin, it was not uncommon to have the lead units in dynamic brake while going down a grade, with the reared DPU in power, when negotiating the roller-coster Oran Line south of Gillette, WY. The headend would be going downgrade, while the rear of the 130 car loaded coal train was still climbing the previous grade. 

As the Engineers became more experienced, the cases of broken knuckles dropped over 90% within the first two years of SD70MAC operations.

 

I'm  interested in what" special instructions"   are available to crews either on the road, or crews who make up these types of  trains at the initial terminal.. I'll eventually find the answer. The yard master is definitely involved since his or her crews make up the train.

Ex. how many cars or tons  can we put between the  lead and middle units?   Something along those lines.

Gregg posted:

I'm  interested in what" special instructions"   are available to crews either on the road,

Once the operating crews are trains, why would they need "special instructions"?

or crews who make up these types of  trains at the initial terminal.

The Mechanical Department Electricians perform the DPU set-up and "link-up" between the various units in a DPU consist.

 I'll eventually find the answer. The yard master is definitely involved since his or her crews make up the train.

Maybe in your country, but here the "Yardmaster", now probably called an MTO, i.e. Manager of Terminal Operations, is just doing what he is told/directed by the Motive Power Desk.

Ex. how many cars or tons  can we put between the  lead and middle units?   Something along those lines.

Gregg posted:

Great replies and thank you.   ( There's an expression on the railway...You can lean something new every day)

At  the initial terminal where the train is made up. I wonder what special  instructions  are issued?

 

This is where optimal train handling comes into conflict with other realities and a deal must be made.  The considerations are:

• In a unit train,* the very best placement of a single remote consist is ahead of the 25% of tonnage at the rear of the train if  the remote and the head-end locomotive consists are equivalent in horsepower and tractive effort. In modern times, this would usually be a mixture of EMD and GE 4300 horsepower units, 2 in front and 2 in remote.
• However, it requires time and track to bury a remote consist in the train at the originating terminal and dig the remote consist out at the final terminal, except at the small number of yards designed for this.  With the length of crew districts today, the road crew could easily go dead on Hours of Service if they have to perform this work.  If a separate crew (some times two - a switcher crew to pull the rear of the train back, and then re-couple it after the hostling crew brings the remote consist out from the storage track or engine service track and places it in the train) performs the work, there is additional cost, and, because of the uncertainty of availability of additional track space to do the switching, can make it very hard to get the road crew called on duty at a time that will allow them to review their Track Warrants and Track Bulletins, check the train list, and get out to their train which is ready for them.  As Wyhog pointed out, many coal unloading facilities will not clear the remote locomotive consist in the loader or dumper, if this is a coal train being delivered to a power plant.  If this is a stack train, there has to be more switching at the final terminal as opposed to pulling into one intermodal track and, when the rear end is into the track, cutting off the head portion of the train and doubling it over to an adjacent intermodal track.  This kind of delay is generally intolerable today, and is dictated by policy, instead of by rules.
• In a conventional freight train, things can get complicated.  Each railroad has its own rules, but they are similar.  The remote consist is ideally placed in the train using a formula for how much train length and tonnage should be behind the remotes.  However it is necessary that the remotes not be placed behind groups of very light cars, groups of long and short mixed cars, to avoid shoving them off the track on curves and in undulating territory.  It is more difficult than you might imagine, to apply each of the rules and get the remote engine placed properly.  Also, if the train picks up or sets out cars en route, the formula has to be re-checked to avoid violating helper placement rules in the newly revised train.  This is why you do not see as much use of DP in conventional freight service.
• Therefore, remotes are most commonly placed at the rear of unit trains for avoidance of delay where the remotes are added and removed, and for ease of unloading the train.
• In the case of Kansas City Southern, which was mentioned in a previous post, this is a special situation in which the layout of their yard tracks allows the train to easily be placed on two tracks and the mid-train remotes added to one portion, and then the road crew could come on duty, double the head portion over to the rear, condition the Distributed Power (which also performs an initial terminal air brake test), and depart.  KCS has what could only be described as an inexpensively-constructed line that goes straight from Kansas City to the Gulf of Mexico and goes over and through anything in the way.  Therefore it has hogbacks, many curves, and some mountain grades to contend with, making the mid-train remote much more useful to KCS than to most railroads.  
• BNSF also adds mid-train remotes into westward heavy unit trains destined for northern California and therefore required to operate via trackage rights on the former Southern Pacific line over the Tehachapi mountains.  (The consideration here is lateral buff and draft forces due to the many, many curves in 2.2% mountain grades on the SP.  There's not much straight track on Tehachapi.)  It's easy to do at Barstow because the train can pull into an Inspection Track, double the front half over and a hostler crew can have the remote consist coupled to one portion while the inbound and outbound crews are exchanging information. The outbound crew doubles over, conditions the Distributed Power with yard help, and they're gone.  At Bakersfield the reverse occurs, and the Valley crew doubles over and scoots up the flat San Joaquin Valley with only one remote consist at the rear.

Distributed Power is a wonderful tool.  It almost always works as intended -- much more reliably than Locotrol II -- and allows long, heavy trains to operate at up to 70 MPH.  Every day there are stack trains over 2 miles in length, parting the breeze at 70 MPH across the prairie here, using 4 units on the point and another 4 on the rear.**  You just have to make the necessary compromises to get full advantage from it without letting it be a handicap.

* Any heavy unit train -- coal. potash, grain, tank cars, intermodal.

** 4 and 4 are used instead of 2 and 2 to get enough horsepower to sustain high speed running.  Tractive effort is mostly determined by the weight on drivers, while speed requires horsepower.  Thus, the difference.  The Joseph City coal trains used 4 and 4 also, because they had to run "in the pack" with the dozens of 70 MPH intermodal trains.

I find these train handling discussion fascinating. Tom and Wyhog, you guys are both GREAT writers and I enjoy every word of your commentary. I also learn something from you guys almost every time you post.

While I had a rewarding career in the railroading industry, it was not in this kind of heavy train railroading. Four GP10 units and 40 loads on 2.2% was the toughest situation I typically faced. We were fortunate that the empties always went DOWN that hill...with no dynamics and careful handling of the air and slack.

OGR Webmaster posted:

While I had a rewarding career in the railroading industry, it was not in this kind of heavy train railroading. Four GP10 units and 40 loads on 2.2% was the toughest situation I typically faced.

Don't sell yourself short, Rich.  Big locomotives and extended range dynamic brake can compensate, to degree, for a mediocre Engineer.  I'd call four GP10's and 40 trailing loads on a 2.2% grade "real man's railroading."  

One summer I worked the second San Jac Local, which used 4 well-worn geeps to haul about 40 ice bunker and mechanical reefers over the 90 pound jointed rail and light ballast, up a 2.2% grade loaded with 10 degree curves, from Highgrove to Box Spring, went out to San Jacinto to get them all loaded with potatoes or onions, and then hauled them back down the hill.  That was no job for a beginner, in either direction. It required the Engineer to "know the air" to get down the hill without looking like a rolling forest fire, as well as some tricks to keep from stalling or breaking in two going up the canyon. Oh . . . and just to make things more interesting, there was an automatic interlocking at the bottom of the hill, and still on the grade, where an orange grove and a curve created a short sighting distance for the signal.  

That kind of railroading made me a better Engineer, just as it did for you.  You get a tip of the hat and a fist bump, for being a veteran of "real man 's railroading."

"extended range dynamic brake can compensate for a mediocre Engineer"

An interesting and timely statement.
I just finished listening to a podcast by Frank Dernie about Formula One racing and his take on the cars and drivers of today. Where today's drivers have a fly-by-wire throttle and computer assisted gear changing and how much easier it is for the drivers of today than those of say only a decade ago. 

In comparison, there are different air and dynamic brake skill sets that an engineer had to learn in order to properly handle a train. If a young engineer has only been trained using extended range or AC dynamic brakes and has never had to handle a train with only conventional dynamic braking, Tom's statement rings true.

However, to one who has grown up using the different combinations of dynamic braking, it can also make one a better engineer. Gee whiz, AC units can almost, if not, stop a train (depending on grade and tonnage). Makes things a lot easier, especially after recovering from an undesired brake application and staring a red board in the face.

All the more reason to learn everything you can about your job. And, more importantly, for the RR company officials to allow their engineers to be properly trained for ANY situation! To quote the Top Gun School motto..."Train like you fight, Fight like you train".

"If you don't get out of DB (and release any airbrake you had to use) and get into full power quickly the train speed will rapidly decrease going up the next hump."

Impossible to do with GE units! 

Wyhog posted:

And if we are keeping score, I do believe your King Air beats my Cherokee ;-)

LOL!

However, it's not "my" King Air. I'm just the hired airborne bus driver for the owner...you know...the guy who has the real money.