wunder beta📘 How does the transport system work?
The bananas did not grow in this aisle. You are looking at the last two metres of a transport system.
What you’ll learn
- Two ledgersSeparate the passenger highway ledger from freight, and show why tons, ton-miles, and trip length disagree.Highways are mostly people. Freight is a different count: trucks take most U.S. tons, rail looks larger once distance is in the unit, and most freight trips are short.
- Four ways to move a tonGive each mode the job it is actually for: door, distance, ocean, time, and pipe.Trucks are doors. Rail buys distance on private track. Ships take around 80 percent of international trade volume. Air is time. Pipeline is the hidden bulk mover.
- The boxShow how a detachable container, then a shared size and a check-digit number, made modes interchangeable.Ideal X carried 58 truck bodies in 1956. Stacking beat wheels. ISO 668 standardised 20- and 40-foot boxes; ISO 6346 put an 11-character number on the door.
- Who owns the pathContrast public roads and layered ATC with privately owned freight rail, and follow a sealed box through handoffs.Roads are public; Class I track is mostly private. Intermodal keeps the cargo in the box. A flight is handed from tower to TRACON to Center and back.
- What you can actually seeLeave the reader with a chassis, a well car, four letters on a door, and a question about short-haul geography.The last miles are a truck because the door is on a street. Read the prefix. Ask which machine did the long haul.
Questions this course answers
Which statement matches the 2023 U.S. freight picture CRS drew from BTS?
CRS, from BTS Freight Facts and Figures for 2023: truck about 65 percent of weight and 44 percent of ton-miles; rail 8 and 19; multiple modes 3 and 10. Pipeline is named as the second-largest share by weight, which is why it is missing from a surface-mode table, not because it is small.
Match the mode to the job it is actually for.
Trucks win doors. Rail wins distance. UNCTAD: around 80 percent of the volume of international trade in goods moves by sea. CRS: pipelines are the second-largest U.S. freight share by weight.
About what share of the volume of international trade in goods does UNCTAD say moves by sea?
UNCTAD's standing line is around 80 percent of the volume of international trade in goods, higher still for most developing countries. That is volume, not value, and it is international trade, not U.S. domestic freight.
Order the usual path of a packed intermodal container.
Intermodal means the cargo stays in the box. The vehicle changes. The last miles are almost always a truck because the receiving door is on a street.
What did the Ideal X carry from Port Newark on 26 April 1956?
Smithsonian / Levinson: a crane lifted 58 aluminum truck bodies onto the converted tanker Ideal X at Newark. Five days later Houston trucks took them inland. McLean had first thought of driving whole trailers aboard; he detached the bodies so they could stack. ISO 20- and 40-foot boxes came later. His own early boxes were 33, then 35 feet.
Why can freight rail look small by tons and much larger by ton-miles?
CRS 2023: rail is about 8 percent of U.S. freight by weight and 19 percent of ton-miles. Class I average length of haul exceeds 1,000 miles. Trucks take most of the short trips, so they dominate tons. Rail's fewer loads travel farther, so distance inflates its share once the unit is a ton moved a mile.
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