Another thing to think about is what the other option was when double stacks were first developed. There was still a lot of TOFC at that time. The wind resistance on those was terrible.
A couple of years back, there was a BNSF video that showed a stack train in the Abo Canyon area { at the time , the major construction project was in the process of accomplishment). The engine in that video was equipped with an annometer attached to the cab area. To what Paul Milenkovic noted,it seemed pretty obvious BNSF was gathering some information in regards to winds and areodynamics(?). So there must be some private data in their engineering department(?).
Then of course, because of TRAINS coverage, we knew there was the UPRR's 'AirFoiler' experiment, which apparently, came a cropper when it was damaged under a bridge in Wisconsin. Which apparently, ended their experimentation(?).
Watching BNSF stack trains going thru this area, they seem to use plenty of power to move them (normally, 4 or 5 GE's on the head end). Solid trains of 53' containers on a train (5/6k ft?). Spacing on one of them is pretty close beween containers.
It is the solid Import/Export containers ( 40 to 45 ft) where there seems to be a gap between stacks of something on the order of 10 to 12' (?), The big stacker's with mid train DPU's will have 2 or 3 engies on headend; Mid train DPUs will be 1 or 2 units and on the rear similarly 1 or 2 in DPU. Plenty of HP does not seem to be a problem for BNSF?
I never understood why the fractional improvement in containers per siding-constrained train length added up to an advantage over a number of disadvantages.
For one, the number of containers is not doubled because there are gaps between container wells required for the trucks. I have also seen many a stack train where a goodly number of the cars are only loaded with a single stack of container. Two, it must have cost capital up front to insure that these excess height cars could fit under bridges on the routes involved, and there must be places these cars cannot go. Three, there must be a big boost in aerodynamic drag to have the loaded cars that tall and to have the large gaps between the containers.
Four, I can understand that inbound ocean containers are served by a yard with gantry cranes, but the receiving intermodal terminals need either gantry cranes or Piggy Packers with a high reach. There are side-transfer options for single-level containers, which could reduce the cost of a terminal, allow for more local terminals and reduce the distance and hence cost of drayage (trucking) to the final distination.
Five, with respect to the use of articulated well cars, the intermediate trucks are probably at weight/axle load limits -- evidence of this is the use of a larger wheel diameter that tolerates higher loading. In using articulated cars, the use of "3-packs" may have to do with the articulated trucks all being shared between one end car and one intermediate car that reduces the axles loading somewhat. Limiting the number of articulated cars as does the use of double-trucked well cars on 53-foot trailers also increases gaps and air resistance, which is a major contributor to fuel consumption of fast intermodal trains.
The whole enterprise has a "feel" of optimizing one metric -- the number of loads per train -- without looking at all costs and the "big picture" of an intermodal train as part of a larger transportation system.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
You can thank Southern Pacific, SeaLand, and American Car Foundary for pioneering the concept. Far as I know APL and SeaLand were the first customers to use the service for land bridge traffic.
I don't know the absolute origin but in the mid 1980's Santa Fe President Mike Haverty took Mr. J B Hunt on a business car trip from Chicago to LA behind a Santa Fe fast stack train, perhaps the Super C. As a result Santa Fe got their business along routes which interfaced with its Railway.
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