Just stumbled on YouTube videos from a few days ago that UP has upgraded Big Boy's PTC to full independent operation.

Anybody else expecting this? It was only 1-2 years ago that article in Trains discussed how they thought they would always run with a diesel helper, and now they invest in independent operation!

https://youtu.be/SCMuWfDr4_4?si=QtdLbQqISc0UFeAY

And another one

https://youtu.be/KclceG04qeQ?si=3yE-RVMHiaOujN2v

The reasons for the diesel existed before the installation and will exist after. It's operational flexibility, maintenance reduction, range extension, and basic steam railroading on the mainline in the 21st century. Ed's comments on why the diesel is in consist have been consistent regarding the reasons above. 2816 has an independent installation and carried diesels on it's trip and I'm guessing the reasons are the same.

But he's right: the argument even fairly recently was that the installation of full independent PTC was too expensive, and too technically 'hard', for preservationists, so the approach would be to fit a remote position sensor on the pilot beam and a control box for the trailing diesel and use the PTC on that trailing power.

All these modern installations are autonomous. You'll still want a control box for trailing diesels in the cab. But the diesels don't have to be there, or be running, for the steam locomotives to be able to operate legally.

Assuming UP plans to continue keeping a diesel in the consist then the only real benefit I see to this independent implementation is to allow flexibility in which diesels are used. With the LEAP system, UP 4015 was more or less permanently assigned to the steam program. In the case of CP 2816, my understanding is that their initial plan was to use the LEAP system, but found it to be incompatible with the FP9 locomotives, hence the full independent installation.

It's not a huge deal for a class 1 railroad to do this, but the issues remain for for most preservation groups. The physical installation of either full independent or LEAP is fairly straightforward albeit very expensive, but who is is going to handle the back-office support, software licensing, etc? The initial thought was that LEAP would be the answer as those aspects would be handled by the hosting railroad. However, feedback is that railroads really aren't interested in modifying a diesel to assign to limited steam moves. This is why many steam organizations are now abandoning their LEAP plans and pivoting towards a full PTC installation goal. That still leaves open the issue of finding a railroad willing to host the engine within their PTC network.

Where there is the will......there will always be a solution found.

Onward & Upward.

Ross Rowland

Add to that dynamic braking. Regarding range extension, as it was explained to me, in addition to having the diesel take some of the load thereby stretching the steam locomotive's fuel and water range, having the diesel control handy allows the steam engine crew to "set and forget" the steam locomotive's controls, and just add or subtract a notch or two on the diesel throttle as changes in grade demand, leaving the crew with more time to watch where they are going.

It’s nice to know that a steam only outing COULD happen - even if the chances are slim. I sure got lucky when I rode the last mainline trip for the 261 and Amtrak conveniently had a shortage of locomotives. Was my lucky weekend! Haha.

While historic operations are cool - there is also something equally cool about mixing history and modern technology - I’m sure it’s fascinating how they have done this.

Hello.

Perhaps it’s already been explained here. What has been the final design settled for independent steam PTC?

Is it brake application only or is there also a modification to close the front end throttle when an alarm trigger is made (Alarm #2) ? ….both braking and throttle closure simultaneously?

In looking at online videos from the AAR, UP and BNSF, they cover the highlights and only talk about brake applications in diesel locomotive PTCs. A modern diesel engine (the prime mover itself) has its own computer control unit for air fuel ratio control, fuel injection rates, etc. I guess it goes without saying, when the PTC trips the second alarm, it sends an output signal for the engine to go to idle, unloads the main generator along with the brake application?

With steam locomotives, the brakes can be potentially applied automatically (with steam PTC, they use a modern diesel loco brake stand or system?). As for the steam front end throttle, it’s all manual. Have the main line steam operators developed a common design which is getting shared for throttle control? If so, do these systems need approved and will be inspected by the FRA?

They indicate the PTC software platform is uniform across the roads so they can share diesel power or allow run throughs.

4014 and 2816 have stand alone PTCs, do they share the same throttle control concept? Assuming this may be developed for the 2926?

The merger of modern control systems into heritage equipment is really interesting!

BTW, from the field videos from this week, the foamers chasing the 4014 across the desolate dead flat landscape on packed gravel roads reminds me of the films from the chasing of Class 25’s on the Karoo in South Africa! ;-)

Cheers

Randy Musselman

When NJTransit upgraded the 614's systems in 1998 they worked with the FRA and Union Switch & Signal when installing the cab signal/ATS system in conjunction with upgrading the brake system from 24 to 26.

To satisfy the ATS systems software demand that the throttle be completely closed when certain penalty applications were called for, we installed a small talgo type switch of the throttle quadrant at about the 1/4 open position, which when activated told the microprocessor that the throttle was in the closed position.

The FRA accepted this solution knowing that to keep lubrication going into the valves/cylinders some steam needs to be fed until a complete stop occurs.

In that a mainline steamer operating with cab signals/ATS will always have at least 2 crewmen in the cab AND when the train brakes are set into a full service application that train will stop quickly no matter where the throttle is set.

I suspect that the 4014 and 2816 have worked out a similar arrangement??

Ross Rowland

I understand that the FRA accepts that the brake application only is sufficient. One of the ideas is that a steam locomotive isn't going to be running with only one person in the cab, more likely she will have several people. At least one person should notice that they are supposed to be stopping...

Thank you Ross and Kelly for the replies. It’s interesting the brakes only have that much capability. You both made a good point. There are at least two in the cab VERY situationally aware. If it gets to level two, maybe they should not be in there!

The only caveat is money - sometimes the money overcomes the will before the way can be found.

Money is rarely the issue - rather it is the excuse.

Norfolk Southern and BNSF have the same amount of money (basically) as UP and CP - but they don’t have the same will at the moment.

CZ, If you're talking about the lack of their steam programs (or their unwillingness to host steam), it's not about the piggy bank, it's about who is holding the purse strings. In an age of PSR, hostile hedge funds, operating ratio targets, it's an amazement to me that CP and UP even invest money in a steam program.

In regards to this thread above, I am convinced that even if a steam locomotive can be PTC compliant solo, without a diesel escort, it still will absolutely have one because of risk mitigation. Can you imagine what would be said in the next shareholders meeting if the 4014 broke down for an extended period of time and stymied the system for a day? Derailments are bad enough. Why give any ammo to the loudest critics and risk your program? In my opinion, that diesel in consist is here to stay.