Maybe a silly question.... Container Trains

[ChiefPlanner]

From my own "intermodal" days (admittedly in another century !) - 30ft Freightliner domestic boxes was a development on the standard 20'ft box ("N"types) - and partly replaced by 40ft 8'6 boxes for domestic use which was an effort to fight back against the road haulage "cube" competition.

30ft steel boxes were very common on European short haul traffics - the likes of Seawheel / International Ferry Freight , Geest North Sea line and SNCF subsidiary CNC

So 45ft "boxes" seems a logical development.

 

[themiller]

From my own "intermodal" days (admittedly in another century !) - 30ft Freightliner domestic boxes was a development on the standard 20'ft box ("N"types) - and partly replaced by 40ft 8'6 boxes for domestic use which was an effort to fight back against the road haulage "cube" competition.

30ft steel boxes were very common on European short haul traffics - the likes of Seawheel / International Ferry Freight , Geest North Sea line and SNCF subsidiary CNC

So 45ft "boxes" seems a logical development.

The only 30’ containers that I’ve seen in recent years have been silos of IFF/UBC and tanktainers while I’ve been abroad in Europe.

 

[CW2]

30 foot containers were (and probably still are) popular for "bag-in-a-box" type transportation of chemical in powder or pellet form. They were ideal paired on a 60 foot flat wagon, provided they were within the weight limits.

I recall an incident in Zeebrugge, when the (French-speaking) customs official decided to check the container, so opened the container doors, to be met by an avalanche of powder in a plastic bag! Try as he might, he couldn't close the door again. Eventually we had to hire a crane to lift the container on its end to get the bag back in the box. The shipper complained loudly and at length about the delays to his traffic, until it was pointed out that the instructions "Bulk Powder, Do Not Open" were written in English, German, and Dutch on the container, but not French! I don't think the same mistake was made again.

 

[country_end_37]

There were a couple of cases like that on Horseshoe Curve in Pennsylvania a year or two ago. A number of wagon bodies (less bogies) were left alongside the tracks within view of a webcam for some months until a full track closure allowed their recovery.

A mile long counts as short on US transcontinental stack trains - two to three miles long is routine, usually with distributed power at mid-train or rear, or occasionally both. That's around six to eight 4000+ hp locos on one train.

When moving from Pennsylvania back to Europe, I was quite excited to realise that my 20' container of furniture, books, household goods, etc, was going to go by Norfolk Southern from Pittsburgh to a freight terminal at Elizabeth NJ—and would be going around the Horseshoe Curve. I'd been round it a few times as an Amtrak passenger, but somehow knowing that all my stuff was going to be tackling it too was oddly poignant. Glad it didn't fall off.

 

[Adrian Barr]

The original question has already been answered, but it mentioned London Gateway and I thought this might be some interesting background information on container loading there:

There is a lot of information online about how the port and rail terminal operate. On the port website - https://www.londongateway.com there are rail schedules and vessel schedules showing arrivals and departures. DP World (port operators) have a Youtube channel which explains various operations at the port in different videos. There is also this speeded-up cab ride along the branch into the terminal:

Boxes are offloaded from ships onto the dockside by the giant quay cranes and then moved by straddle carriers to an automated container stacking area which also loads lorries. Containers for the rail terminal are moved from the stacking area by internal port tractor-trailer units, and left on their trailers to be picked up by the gantry cranes in the rail terminal.

These videos, watched in this order, show the general sequence from ship to train (I'll link the channel rather than all the individual videos) - https://www.youtube.com/user/londongateway/videos

DP World London Gateway operations on Barzan, one of the world's largest container vessels [ship unloading]
DP World London Gateway Quayside Loading and Unloading
Episode 2 London gateway: Living the High Life [Quay crane operator]
Episode 4 London Gateway: Stacks of choice [Terminal tractor movements, stacks to rail terminal]
Episode 5 London Gateway: Working outside the box [Gantry crane operator in rail terminal]
DP World London Gateway - Rail Operations
DP World London Gateway Rail Terminal Time-lapse [Train loading and unloading]

Clearly there is pre-positioning of containers (which will be based on a loading plan) so that the cranes don't have to wait for them, or constantly shuttle backwards and forwards along the length of the train. I think there's a mix of factors already mentioned that determine loading patterns - the ideal of loading containers from the loco backwards to minimise wind resistance, vs the various weight and container height restrictions of different wagon types, and the desire of the terminal or port to make the loading as simple and efficient as possible for themselves, with often limited time for unloading and reloading. Add in the occasional defective wagon that can't be loaded, a mix of wagon types, a few containers which missed the cutoff time, and you get a puzzling end result of apparently random gaps on some trains.