Transportation Logistics & Traffic Systems

# Transportation Logistics & Traffic Systems Knowledge Pack

## Supply Chain Logistics

### Freight Transportation Modes
Each mode has distinct cost, speed, and capacity characteristics that determine optimal use:

**Trucking (road)**: Most flexible mode — door-to-door service, no transshipment needed. FTL (full truckload, 40,000-45,000 lbs) costs $1.50-3.00/mile, transit time 500-600 miles/day. LTL (less than truckload, 150-15,000 lbs) consolidates multiple shippers onto one truck, costs more per pound but less total for smaller shipments. LTL typically adds 1-3 days for terminal handling and sorting.

Driver hours-of-service regulations limit driving to 11 hours within a 14-hour window after 10 consecutive hours off. Electronic logging devices (ELDs) enforce compliance. Team driving (two drivers alternating) enables near-continuous movement for time-sensitive freight.

**Rail**: Lowest cost for heavy, bulk freight over long distances. Intermodal (containers on flatcars) competes with trucking for distances >500 miles. Cost advantage: one train replaces 280+ trucks, consuming 1 gallon of fuel per ton per 470 miles vs. 130 miles for trucks. Disadvantage: slower (25-35 mph average including dwell time), less reliable schedules, requires truck drayage at each end.

**Ocean**: Moves 90% of global trade by volume. Container ships carry 10,000-24,000 TEU. Transit times: Trans-Pacific (Asia-West Coast) 12-18 days, Asia-East Coast via Suez 28-35 days. Cost per TEU: $1,000-5,000 depending on trade lane and market conditions. Vessel sharing agreements and alliances (2M, Ocean Alliance, THE Alliance) dominate major lanes.

**Air**: Fastest but most expensive ($4-8/kg vs. $0.10-0.30/kg ocean). Used for high-value, time-sensitive, or perishable goods. Represents <1% of global freight by weight but ~35% by value. Belly cargo (passenger aircraft) supplements dedicated freighters. Express integrators (FedEx, UPS, DHL) operate hub-and-spoke networks with guaranteed transit times.

### Warehouse Operations
The WMS orchestrates all warehouse activities: receiving (inbound inspection, putaway assignment), storage (slotting optimization — high-velocity SKUs in prime pick locations), picking (single order, batch, wave, or zone picking strategies), packing, and shipping.