Doublestacks on the NEC

I've been reading and posting in a few threads related to electrification and NEC freight. Does anyone know if NS runs international doublestacks at 18'02" ATR down the NS Port Road line and down the NEC from Perryville to Baltimore?

AFAICT, that route is not cleared to domestic doublestack Plate H at 20'02" ATR, but is definitely cleared to 19'00" ATR for autoracks, as NS runs them down to Baltimore. It's unclear if there is an additional 2" of clearance for a domestic 53' on top of an international 40' at 19'02" ATR.

I have found videos of NS running a very small amount of international container traffic, either as single-level in well cars or as COFC, as well as TOFC and TOWC (Trail On Well Car), but I cannot find any video of double stacks on the NEC.

Is there just not enough traffic to justify it? Or does Amtrak have a restriction specific to doublestacks, even though international double stacks will clear on that route with 10" to spare?

Some digging on Google unearthed a random Medium blog post which claims that the structure gauge of the Northeast Corridor is Plate B, which (according to Wikipedia) requires vehicles with truck centers of 41 feet 3 inches, versus 46 feet 3 inches for the other gauging classifications. Combined with the obsolescent positioning of the PRR catenary above the structure gauge, I suspect that Amtrak specifically prohibits double stacks to minimize the risk of an arc to ground that could cause a fire or bring the wires down, and to minimize track wear and risk of derailment from the larger vehicles.

I look forward to learning the actual regulations surrounding the procedures for freight access.

TheOneKEA wrote: ↑Sun Nov 03, 2024 9:08 amSome digging on Google unearthed a random Medium blog post which claims that the structure gauge of the Northeast Corridor is Plate B

The clearance on the NEC ranges from 14'6" with clipped corners in the North River Tunnels, which is sub- Plate B, to at least 19'0" ATR in a section in Rhode Island and the section that I'm discussing here from Perryville to Baltimore, both of which have regular movements of 89' 19'00" ATR autoracks.

Looking at CSX's plate clearance map combined with knowledge of LIRR, Amtrak, and NJT equipment, there is no Plate B restriction on the northern half of the NEC, with everything either at Plate C or higher, or around NYC, 14'06" square in the East River Tunnels and 14'06" with clipped corners in the North River Tunnels. It's possible there is somewhere on the south half, but AFAIK, Plate C can get all the way from Washington DC to North Jersey.

which (according to Wikipedia) requires vehicles with truck centers of 41 feet 3 inches, versus 46 feet 3 inches for the other gauging classifications. Combined with the obsolescent positioning of the PRR catenary above the structure gauge, I suspect that Amtrak specifically prohibits double stacks to minimize the risk of an arc to ground that could cause a fire or bring the wires down, and to minimize track wear and risk of derailment from the larger vehicles.

All of that is irrelevant, as the section that I am asking about has 19'00" ATR clearance for 89' autoracks, which is plenty for 18'02" international double stacks. My question is whether they have ever been run from Perryville to Baltimore, and if not, if Amtrak has an arbitrary restriction on them on the NEC.

As for tonnage, while a 20-20 combo on the bottom with a 40 on top can get pretty heavy, NS occasionally runs ginormous unit coal drags on the NEC from Perryville north to Wilmington, DE, so wheel/rail wear alone or some other issue related to tonnage doesn't really explain it. They could also just allow 40-40 combos and require 20-20s to be single stacked.