The process of repositioning an empty railcar after it has been unloaded, either back to the car owner, to a new loading point, or to a storage location. Empty movements generate no revenue and are a significant cost component for railroads. Optimization of empty returns is a key factor in fleet management.
The formal notification given by a shipper or consignee to a railroad that a car has been loaded or unloaded and is ready to be pulled. Release marks the end of the customer's responsibility for the car and triggers the railroad's obligation to retrieve it. The release time is used to compute dwell and demurrage.
A compensation system under which a railroad pays a daily or mileage-based fee to the car owner when using foreign-owned or privately owned equipment. Car hire rates are established under AAR rules and are intended to recover the owner's fixed and variable car costs. The system balances car supply across the national rail network.
A railcar owned by a shipper, leasing company, or third party rather than by a railroad. Private cars are used by the owner to transport their own goods or are leased to shippers for dedicated use. The owning railroad receives car hire when private cars travel on foreign lines.
A railcar owned by the railroad on whose tracks it currently operates. System cars are available for general loading and are managed as part of the railroad's own fleet. When system cars travel on another railroad, they become foreign cars and earn car hire for the owning road.