Freight Car Friday – Spine Cars

4 04 2014

Articulated “spine cars” are a common sight on North American mainlines today as they carry trailers and containers in priority intermodal trains. While their use has exploded in recent decades, the history of this “bare bones” car goes back much further.

skeleton car

The skeleton log car was more efficient in mountain operations.

The earliest spine cars weren’t used to haul trailers or containers. In fact, they were about as far from the high-speed freight intermodal market as you could get! Used by logging companies as early as the late Nineteenth Century, the basic spine car offered a vehicle with a minimum light weight and easy unloading of large logs.

Simple to build, these cars were not much more than trucks and a center frame or “spine.” Cross beams over the truck helped support the log loads. Stacked and chained down at the logging camp, once the logs arrived at the mill unloading was a simple matter of unbuckling the chains and tipping or pushing the logs off and into the mill pond.

front runner

The Front Runner took minimal design to the limits – or maybe just a bit too far beyond them. One example was literally plucked from the scrap line for preservation at the Museum of Transportation in St Louis.

Eliminating the cost, weight and maintenance of a flatcar deck made sense in this service. It would be many decades however before the idea found a practical use in common carrier rail lines.

The first uses of spine cars in intermodal service began in the late 1960s with projects like the Clejan car on the New Haven and Southern Pacific and the better-known Flexi-Van cars on the New York Central and several other railroads. Like the logging spine cars, the basic premise behind these designs was to reduce the weight and cost, and inefficiencies of the flatcars currently used in Trailer on Flatcar service.


A 5-unit spine car loaded with 53′ domestic containers is a contemporary staple. This car can also carry trailers.

These pioneering spine cars were similar in length to the longer flatcars then in service for hauling trailers, 75 feet. Of course you couldn’t load these cars the same way you’d load a conventional flatcar, and therein lay the real drawback to the designs. The FlexiVan car used a turntable on the spine to pivot the container load so that no special cranes were needed. But this had its own set of problems from extra maintenance and complexity on the cars to a need for empty chassis at each terminal. For the efficiencies of the cars to be realized, railroads would also have to redesign the terminals and purchase new equipment to load and unload the spines.

As intermodal trains continued to evolve into longer-haul services from fewer dedicated hubs in the 1970s, the climate improved for alternatives to the flatcar and conventional “circus style” loading. In the 1980s, the first new spine car to have a major impact was the “Front Runner” – a single unit car whose construction took minimization to the extreme. The central spine had two platforms attached at one end to support the trailer’s wheels. It rode on two axles with only 28″ wheels to lower the total height. The cars were light – too light – and were prone to derailments, especially when running empty and mixed in with heavier, traditional equipment.

trash spine

Although normally thought of for traditional intermodal containers and trailers, specialized spine cars can be found in waste container service as well.

The advantages of this reduced design were apparent however and railroads, car builders and Trailer Train all partnered to bring new designs to the rails. By the end of the 1980s, the five-unit articulated spine car emerged as the new standard. Articulation allowed use of conventional trucks while further reducing weight and coupler slack in a train. While some early spine cars were trailer only or container only, dual-capacity cars soon emerged for greater flexibility and fleet utilization.

Since then, the overall form of these cars has changed little. The most consistent change was an ever-increasing length of the individual cars to accommodate longer trailers. Today both three and five-unit cars are common. Together with the double-stack container well cars, these platforms form the “backbone” of the North American intermodal fleet.

Freight Car Friday – TOFC Flatcars

7 03 2014

Today’s intermodal equipment takes many forms. For decades however, there was only one standard – the flatcar.

early flat

An early Trailer Train 75′ flatcar is preserved at the Virginia Museum of Transportation with a load of two Sea Land containers on chassis. It is hard to imagine a more perfect car to describe the heritage of the modern railroad era!

The origins of TOFC, or Trailer On FlatCar, service began in the Nineteenth Century. It wasn’t until the mid-1950s however that the service began to grow into the important traffic source we know today. The common term “Piggyback” as applied to this service actually originated with Pullman Standard advertising in 1954.

In the first decades of TOFC, two types of flatcars emerged. New cars dedicated for hauling trailers were built, most to a length of 75′. The cars were long enough to hold a pair of 35′ trailers. While the cars were long compared to conventional freight cars of the era, they were no longer than passenger equipment and few railroads had any issues with interchange of the cars in most traffic corridors.


Lionel’s early TOFC flatcars represent common adaptations made to the PS-4.

By carrying two of what were at the time the largest trailers on the road, the 75′ flatcar offered a more efficient car weight / capacity ratio. And the new dedicated cars were designed for much more efficient loading and unloading, using collapsible “fifth wheel” hitches. The rub rails along the sides of the cars could be used for additional tie-downs and also to help prevent a trailer from being backed over the side when loading.

As the service took off, new cars could not be purchased fast enough. There were also roads that could not afford the new equipment. This led to a movement to convert older, standard designs for TOFC service. Most common were the conversion of 50′ cars which could hold two smaller 25′ trailers or a single larger trailer. While less efficient in service than the modern cars, these were cheaper and faster to put in service and had the advantage of equally quick to convert back into standard flatcars if demands changed again.

The 89' flatcar became an intermodal standard in the 1980s. The ACF-built "F89-J" class cars were some of the most distinctive. A modern 53' trailer creates a loading challenge however.

The 89′ flatcar became an intermodal standard in the 1980s. The ACF-built “F89-J” class cars were some of the most distinctive. A modern 53′ trailer creates a loading challenge however.

The balancing act between efficiency and production costs would continue to define TOFC flatcars over the coming decades. One of the biggest forces driving a constant change in the cars was the trailers themselves. As trailers grew ever larger, the flatcar also had to expand to keep pace. 40′ trailers pushed the development of an 85′ car. No sooner were these starting to be produced than trailers grew to 45′ and the 89′ car became the new standard intermodal flatcar.

The 89′ Flatcar became a versatile platform for many different types of loads. For TOFC service, most could haul a pair of trailers up to 45′ in length each (each overhung the end of the flatcar by a few inches – accommodated by a longer coupler shank.) Others were equipped with hitches for three smaller 28′ “pup” trailers favored by the LTL (Less than Truck Load) and parcel carriers. In addition to trailers, many flats were designed for the option of carrying containers as well. We’ll talk about these in a future blog.

NS flatcar

First built as a boxcar, then converted to a TOFC flatcar, this Norfolk Southern flatcar is in the shops for rebuilding once again into a crane idler car.

During the reign of the 89′ flat, many intermodals switched from the old “circus style” loading to using large cranes or special lifts to load the trailers. The 1980s saw the removal of the bridge plates from the ends of the cars which had allowed the trailers to be moved across the gaps during loading.

While the 89′ flatcar was the most common in this era, shorter “conversions” were also still found. Like the early days, these were done to fill a rapidly growing need at low cost using existing equipment. Most telling were conversions made not from flatcars, but older boxcars. The rise in TOFC traffic was seen as conventional boxcar traffic was in decline. Several railroads sent unused boxcars into their shops, cut them down and converted them into dedicated TOFC flats. To reduce weight further, and with trailers now being loaded by crane, many of these cars only had a partial floor – another sign of changes to come.

Long Runner

One solution to the challenge of growing trailers was the “Long Runner” – a pair of flatcars semi-permanently coupled. Notice how the center trailer spans the gap.

While the railroads enjoyed a fleet of tens of thousands of 89′ flatcars, the trucking company continued to push for even larger trailers. When 48′ and then 53′ trailers arrived on the scene, the utility of the 89′ flatcar had been exceeded. Extending the length of the car was no longer a practical option. Single-trailer loading offered not only a very poor weight efficiency, but add fuel costs as the large open spaces between trucks created additional wind drag.

scrapped flatcars

While many TOFC flatcars were repurposed, like so many important cars in the evolution of railroading, their ultimate fate is here.

In order to extend the life of many flatcars, companies like Trailer Train and Florida East Coast began joining a pair of cars with a drawbar. With a single trailer up to 57′ in length on each, a third could be placed across the gap. Some of Trailer Trains earlier “Long Runner” conversions also required widening the deck and sides to accommodate that center trailer’s bogie as it slid across the deck through curves.

By the early 1990s however, the need for non-conventional equipment for handling trailers had become obvious. Rather than adapting for intermodal use, many 89′ cars were modified for hauling other loads – everything from heavy equipment to pipe, to auto frames and rail. Articulated platforms offered much greater efficiency in operation than the traditional flatcar. While you will still see one occasionally in an intermodal train, the presence of a true flatcar is becoming quite a rarity.

Freight Car Friday – Roadrailers

28 09 2012

When is a freight car not a freight car? When it’s a truck. The Roadrailer is a unique intermodal vehicle that is both. These highway trailers / railcars have had a long and interesting story.

Early History


A Norfolk Southern Roadrailer train heads east against a summer sunset in Ohio.

Many think of intermodal and Roadrailer technology as something relatively new. The Chesapeake and Ohio introduced the first Roadrailers on the rear of passenger trains between Detroit and Grand Rapids in 1955. The short, 29′ vans were coupled to the back of the daily trains and carried mail and other less-than-carload traffic. Compared to today, the operation was as diminutive as the equipment but it paved the way for future developments.

The bi-modal concept went into hibernation for over a decade. In 1981, this very week in fact, a new generation of Roadrailers debuted on the Illinois Central Gulf. Like the earlier cars, the trailers carried their own set of railroad wheels and were connected to each other with drawbars. While this arrangement reduced tare weight on the rails vs. a traditional trailer-on-flatcar, on the highway the added weight was a detriment. The mechanics of the equipment were another potential problem as well.

Unlike the original service, these new trailers operated as their own dedicated train. After the Illinois Central, several additional railroads experimented with the concept and equipment through the 1980s. They could even be seen running behind EMD F units on CSX. Although the concept was gaining ground, the limitations of the equipment prevented most of the railroads from going forward with the experiment.

Technology Takes Hold

Triple Crown

Triple Crown’s fleet of roadrailers proved the advantages of the Wabash National design.

By the end of the decade, the Roadrailer would mature and begin to shed its railroad wheels. Wabash National, the leading builder of trailers in the U.S., purchased the technology in 1991 and redesigned the roadrailer to be much more like a conventional trailer. The noticeable difference between a Roadrailer and a road-only trailer are the extra connection pins and an air line for the train airbrakes.

The trailers are attached to railroad bogies, or trucks, in the terminal. A pneumatic suspension system on the trailer raises the body to accept the bogie. Once attached, the road wheels are then drawn up for clearance. Trains are built from the back to the front, one trailer at a time, with a single bogie supporting both the front of one trailer and the rear of another.


The “Couplermate” adaptor allows an easy connection to the locomotives. It is the only coupler needed for the entire train.

Once the trailers are connected, the air lines must be connected to the bogies which also hold the brake cylinders. An end-of-train device is put on the rear and a special adapter bogie with a standard knuckle coupler at one end is placed under the front of the first trailer.

Because of the tight connections between the trailers, a train of as many as 125 cars has only six inches of coupler slack. With its light weight and tight connections, a Roadrailer handles much more differently than a conventional train. While in some ways this handling is easier and more advantageous, engineers must still be careful as the structure of the trailers is not nearly as robust as a railcar. A sudden stop or start can tear a trailer in half or crush it like a soda can.

The Modern Era


BNSF’s refrigerated Roadrailers now travel on flatcars. Some retain their Roadrailer hardware however.

Thanks to these improvements, Roadrailers saw an explosion of growth in the 1990s. The largest operator then and now is Triple Crown Corporation, owned by Norfolk Southern. Conrail bought a 50% stake in the company in 1993 which returned to NS during the merger in 1999.

There were several more operations springing up across the country. Santa Fe tested five trailers specially adapted for hauling automobiles. Later BNSF ordered a large fleet of refrigerated trailers for service out of the Northwest. Canadian National and trucking companies Schneider National, Clipper and Swift also bought fleets of Roadrailers.


Amtrak’s first group of Roadrailers were only 48′ long and featured sliding side doors. Triple Crown no longer uses the side doors.

Then the technology came full circle as Amtrak purchased new Roadrailers for mail and express shipments. These rode on the rear of passenger trains all across the country.

The golden years were short lived however. Amtrak soon decided that the added delays to passengers more than offset the financial gains from its Roadrailers and other express contracts. All of the other operations except for Triple Crown also fizzled within a few months or years of inception. Many of these Roadrailers were sold to Triple Crown and are still in service. Others can still be spotted riding conventional intermodal trains as trailers.

ex Clipper

Most of the Roadrailers built in the 1990s are serving their final years on Triple Crown trains, like this ex – Clipper trailer.

Triple Crown continues to operate an extensive network across the northeast U.S. serving many automotive suppliers and other industries with the flexible service. In recent months however the company has begun to show a shift to conventional trailers and rumors abound that within a few years it too may cease Roadrailer operations. Just in case, get out there are see them while you can! Who knows if or when the revolution will begin again.

Intermodal Yards

6 06 2012

Last but not least in our look at railroad yards you can model is the intermodal yard. Intermodal refers simply to any shipment of goods which takes at least two forms of transportation to reach its destination without being unloaded from its original shipping container. Primarily this means truck trailers and containers that can be transferred from road service to rail cars or even ships. Like classification yards, intermodal facilities come in all sizes. From single ramps to massive coastal port facilities, the function of these yards remains the same, only the volume changes.

Loading / Unloading

Piggyback Set

The forthcoming CN Piggyback Set is the perfect way to start intermodal operations on your layout. All you need is a stub siding and a ramp to start your terminal.

Unlike conventional freight yards where freight cars are primarily classified and switched from one train to another, relatively little switching occurs in an intermodal yard. Most loads will either begin or end their rail journey in the intermodal yard. The remainder of the trip is handled by another mode of transportation. Consequently most of the work in an intermodal yard happens around the trains, not with them.

When it arrives in the yard, an inbound train is spotted on a loading / unloading track. Locomotives (and cabooses at one time) leave the train and go to a small storage / service area. Most intermodal yards were built near existing freight yards and locomotive facilities here are normally kept to a minimum. Anything requiring more work is sent out to another shop. Quick turnaround on equipment and trains is essential in this highly competitive market.


The 6-22202 unloading ramp is perfect for small, early piggyback terminals. Ramps like this could be found even in smaller towns where only a car or two were set out. Local intermodal services didn’t last long however.

The train may need to be split into smaller cuts for unloading. This was particularly true when flatcars were loaded “circus style.” Unloading long cuts of cars one trailer at a time over narrow decks and bridge plates was not only difficult but incredibly slow. A larger yard may have several “ramps” to handle multiple cars or even trains at a time. Also important for circus-style unloading was having the trailers pointed in the right direction. If they were backwards, the train would have to be turned, so yards were built near wyes whenever possible.


Modern stack and well cars must be loaded by crane.

Today, most facilities use either overhead cranes or large stradle-lift tractors to remove the trailers and containers. With these, longer tracks are possible to save time. These tracks are normally embedded in pavement with wide accessways along one or both sides for the lift equipment to maneuver and for tractor drivers to position or retrieve loads. In just a few minutes per load, trailers and containers are plucked from the railcar and placed on the ground. Small yard tractors then retrieve the loads and take them to a holding spot briefly until the driver and trucks that will take them over the road arrive.

Once emptied, the railcars are ready to receive new loads for the next outbound train and the process continues in reverse. If a train has more or less cars than needed for that day’s shipments, extra cars may be taken to or retrieved from storage tracks nearby. Extra railcars are also frequently attached to the end of loaded trains to balance equipment if there are more loads moving in one direction than the other.


Although the focus of the activity concerns loading and unloading the cars, switch crews in an intermodal yard do have some work to do.


A yard switcher like our new LEGACY equipped NW2 would be perfect for the light switching duties required around a typical intermodal yard.

In addition to adding or removing empty cars, some loaded cars may make connections to or be combined with other through trains. These operations normally happen at yards built near busy junctions – both with other rail routes and highway access. These switching moves are handled much like those in a conventional yard except that humps can not be used.

The same locomotives used to move these trains over the railroad may also be used for this switching. A dedicated yard switcher might also be present in busier yards.


small ramp

A small ramp like this one is an easy addition to any platform. All you need is a spur, a ramp and a road!

Modeling an intermodal yard is not that difficult. For earlier terminals, a track or tracks leading to a small ramp at the end will comprise the heart of the facility.  To unload the trailers, these tracks had to be straight. For more modern facilities, an operating crane like those made by Lionel in the past is not only a great visual piece but also a fun operating accessory.


By far the biggest need in any intermodal yard is a fleet of trailers and containers and plenty of space for them to move about and to park.

A few extra tracks for rail car storage and plenty of real estate for trailer storage are also needed. Since most of the land in the yards is devoted to this short-term trailer and container storage, a single row of parked trucks along a backdrop or the edge of the layout can be used to suggest just the brim of a larger area on our layouts. Modern facilities are generally completely paved, at least in and around the loading area. We’ll present an article on paving over model track in the near future. Other storage areas may be just gravel or even dirt lots.


Surround your yard with lots of yard lights – like 6-14071 or our other light towers – to protect the valuable cargo and keep the yard working around the clock.

Few structures are found around the intermodal yard. A yard office for handling the billing and check-in/out of the trailers and containers is normally found near the road entrance. At international ports, customs and security buildings could also be found. Speaking of security, with lots of valuable merchandise moving through on tight schedules, these yards tend to be more “fortified” than conventional yards. Security fencing and large light towers are a trademark of these yards which often keep working around the clock. A railroad police car, officers and perhaps a K-9 unit would make excellent and appropriate details to complete the scene.

Last but not least, don’t forget the signage. Directional signs on posts and on the pavement and safety signs abound in these hectic but organized centers.

With the exception of the modern loading cranes and lifts, most of an intermodal terminal can be modeled very easily and at low-cost. Easy to resize, these yards can be adapted to almost any layout to add a new level of operation and interest.