RDC Question

[sirenwerks]

My brain's gone south today and I am getting all sorts of weird ideas.  Must be the 2nd vax shot I got.


But I am thinking about an early Amtrak train idea for my 1974 Oregon-based fictional road and came up with the whacko idea of using a RDC4 as a cab unit with additional power provided by an EMD B unit, and maybe two lightweight coaches as trailers -  maybe an NH orange-nose RDC4 with a SP bloody nose F B unit (or an SP&S Alco FB unit), and coaches still in GN and NP colors.  I'm going for that pieced-together, last kid picked for the team, late doodlebug, mid-level ridership but not enough equipment sort of look.  I don't believe I have ever seen a picture of an RDC unit pulling anything but another RDC, have you?  Did an RDC have enough power to pull anything besides itself and its onboard load?  They were MU'ed, so is the cab unit idea too insane?  I've ridden in RDCs pulled by a loco as a MARC passenger car (I don't believe it was under power when I rode in them). Is the idea just too weird (aside from the truth that I can run whatever I want), were their prototypical limitations that would make operating an RDC with a standard loco impossible?


One more question... Can anyone tell me if the Kato RDC4 is prototypically shorter than its cousins?  It's supposed to be just over 11 feet shorter.

[Mark5]

Interesting idea. When I was teen in the early 70s I actually toyed with wacky ideas on providing rail service on my Appalachian N&W layout (rail service ended on the pokey with Amtrak). But Amtrak solved that issue for me when they formed the short lived Mountaineer, and my layout era slid forward to 1975.

I guess one big question is: can RDCs "MU" with anything besided other RDCs?

[wcfn100]

I don't believe I have ever seen a picture of an RDC unit pulling anything but another RDC, have you?

I don't think they were supposed to pull anything, but there are photos of the M&St.L RDC-4 with a baggage car.

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If you're looking for early Amtrak/RDC inspiration, do a search for the Black Hawk.


Jason

[ncbqguy]

Since I initiated the RDC project while I worked at Kato USA, I can provide some answers...
The Kato RDC-4 is the only scale unit produced in a production model (Lionel made a version!).  It was the lowest volume model of the prototype series and was shorter than the others which is probably why Rapido, LifeLike, Athearn, Con-Cor, and Hornby avoided making them.
The RDC s were not m/u compatible with diesel electrics, only themselves.   As far as pulling trailers, Budd specifically discouraged purchasers from pulling anything....but some ignored their advice.   M&StL and RI come to mind.   The Tootin Louie even built a lightweight aluminum box car for LCL to go with their special RDC-4 that had steps and a small passenger compartment on one end.   The Rock pulled a Budd round end observation car that had a baggage section cut into the end.   But those were on the ragged end of how far the RDCs could pushed.
Charlie Vlk

Jason-thanks for illustrating my comment before I finished my post!   There were RDC-9s for roads that used RDCs in long commuter trains that had a single prime mover instead of the normal two

[thomasjmdavis]

From 1956 until discontinued in 1962 (I think, or 63?), on many days the C&EI Meadowlark to Southern Illinois was comprised of their RDC 1 (which carried the road number "RDC 1") and a coach they had picked up a few years ealier from C&O (C&EI # 467, originally built for Pere Marquette in 1946).  But on days when they expected higher volume of riders, they would occasionally opt for an E unit or FP-7 with 3 or 4 cars.  On low volume days, the RDC would run alone.  Coach 467 was given an independent heating system (no steam gen in the RDC), but also retained its steam heat system to allow for use in regular trains.

We lived in that part of Illinois in the early 60s (I was 8 or 9), I had a ride with Mom on the Meadowlark between a couple of towns- memory tells me just the RDC in the train that day- I don't remember a coach being coupled on- or much other detail.

[Ed Kapuscinski]

Fun fact though, while RDCs couldn't really pull much besides themselves, or MU with other equipment, some did end up being demotered and used as regular locomotive hauled cars.

Basically, the exact opposite of what you're trying to do.

[cjm413]

My brain's gone south today and I am getting all sorts of weird ideas.  Must be the 2nd vax shot I got.


But I am thinking about an early Amtrak train idea for my 1974 Oregon-based fictional road and came up with the whacko idea of using a RDC4 as a cab unit with additional power provided by an EMD B unit, and maybe two lightweight coaches as trailers -  maybe an NH orange-nose RDC4 with a SP bloody nose F B unit (or an SP&S Alco FB unit), and coaches still in GN and NP colors.  I'm going for that pieced-together, last kid picked for the team, late doodlebug, mid-level ridership but not enough equipment sort of look.  I don't believe I have ever seen a picture of an RDC unit pulling anything but another RDC, have you?  Did an RDC have enough power to pull anything besides itself and its onboard load?  They were MU'ed, so is the cab unit idea too insane?  I've ridden in RDCs pulled by a loco as a MARC passenger car (I don't believe it was under power when I rode in them). Is the idea just too weird (aside from the truth that I can run whatever I want), were their prototypical limitations that would make operating an RDC with a standard loco impossible?


One more question... Can anyone tell me if the Kato RDC4 is prototypically shorter than its cousins?  It's supposed to be just over 11 feet shorter.

RDCs were driven by hydraulic torque converters rather than traction motors, so the F7B would be either be dead weight or a really annoying way to power the train.

Using a freight locomotive to pull a dead RDC would be a better option.   I recall finding a picture of an ICG GP8 or GP10 pulling some dead Amtrak RDC's on the Black Hawk.

[nickelplate759]

The B&M pulled strings of RDCs with GP units sometimes, for example in heavy snow.

[spookshow]

Some interesting trivia re the Rock Island's RDC-3 - the trailer car was frequently operated east of Little Rock, even when passenger loads did not require it, because of concerns resulting from the occasional failure of a single RDC to activate the automatic block signal system in eastern Arkansas.

-Mark

[wcfn100]

Some images of the RI Choctaw Rocket here:

https://condrenrails.com/MRP/MemphisCentralStation/RI-Memphis-Pass-Pixs.htm

Jason

[squirrelhunter]

Steve Goen's Rock Island Down South has the kind of info he's looking for as far as RDC usage with non powered equipment.

IIRC, the RI's day Memphis-Little Rock- Okc- Amarillo- Tucumcari train was locomotive hauled the whole way. In the mid 60's they cut the loco hauled part back to OKC or Little Rock and the RDC-3 covered the rest to of the run. The RDC-3 was hauled behind the power in and out of Memphis.

They also used a round end obs with the obs converted to a baggage compartment with the RDC.

Then they cut RDC only part of the run and they removed the diesels from the RDC-3 and used it as a loco hauled combine.

So you could have an F7A or a GP7 haul the train with an RDC or 2 in consist dead to a junction or station, then cut off the power and conventional cars and send the RDC's on their way. Or maybe have the RDC's take a conventional car with them.

[randgust]

Working with tourist railroads I've had more fun than I ever should have with RDC's.

First fun fact is the Detroit Diesel 110's - straight 6 cylinder - and a pair of them.   Canada successfully repowered most of theirs with Caterpillar, today finding 'original' 110's is difficult and those were a difficult motor to maintain for parts.   Many kept at least one running engine just to keep the AC going and disconnected the driveshafts in coach duty.

Second fact is the drive system was unique - they used what's lovingly called 'Spicer Drives' which were military differentials to the inner axles, more or less related to tanks, with the torque converter transmission - not a diesel electric.

Third fact is that apparently the RDC's had a completely unique 33" wheel - not the same as a locomotive, different diameter, and keeping them going meant you had to stock, beg, borrow or steal a wheel supply.  And disc brakes, not tread brakes.

What was rough on them was the stop / hard acceleration up to track speed, and braking hard.   Commuter service beat them up bad.  Canada liked theirs where more time cruising and less time in the stop/start every mile mode.   Tourist railroads that ran them constant low speed and had a parts stock could keep them going.

But as they didn't have a standard MU, and had all those oddball features, every railroad mechanical officer I've ever met hated them.    Putting dead weight behind them was like towing a camper behind a 4-cylinder car, you can do it, but the drivetrain will hate you for it.

Everything you never cared to know about an RDC, here's the owners manual:  https://www.canich.net/bhrs/RDC-1953-GSM.pdf

[dem34]

Working with tourist railroads I've had more fun than I ever should have with RDC's.

First fun fact is the Detroit Diesel 110's - straight 6 cylinder - and a pair of them.   Canada successfully repowered most of theirs with Caterpillar, today finding 'original' 110's is difficult and those were a difficult motor to maintain for parts.   Many kept at least one running engine just to keep the AC going and disconnected the driveshafts in coach duty.

Second fact is the drive system was unique - they used what's lovingly called 'Spicer Drives' which were military differentials to the inner axles, more or less related to tanks, with the torque converter transmission - not a diesel electric.

Third fact is that apparently the RDC's had a completely unique 33" wheel - not the same as a locomotive, different diameter, and keeping them going meant you had to stock, beg, borrow or steal a wheel supply.  And disc brakes, not tread brakes.

What was rough on them was the stop / hard acceleration up to track speed, and braking hard.   Commuter service beat them up bad.  Canada liked theirs where more time cruising and less time in the stop/start every mile mode.   Tourist railroads that ran them constant low speed and had a parts stock could keep them going.

But as they didn't have a standard MU, and had all those oddball features, every railroad mechanical officer I've ever met hated them.    Putting dead weight behind them was like towing a camper behind a 4-cylinder car, you can do it, but the drivetrain will hate you for it.

Everything you never cared to know about an RDC, here's the owners manual:  https://www.canich.net/bhrs/RDC-1953-GSM.pdf

Scale drawings of RDCS? Including all a modeller would need to know about them? Yoink that's mine.

[peteski]

Boston & Maine has so many of them, that they ran multiple sets. But I believe that the ones behind the powered one were "dummies".  Their drive train bits were removed, and they were simply coaches.

[nickelplate759]

The demotored RDCs were used by the MBTA - and B&M GPs did indeed pull them.  But B&M also pulled RDCs (long before there was an MBTA) with GPs when there was too much snow for the RDCs to manage on their own.