The coal cars are unloaded using a rotary car dumper at the power plant.

Loaded coal cars filled with mined coal were moved to a rotary car dumper at the south end of the tipple.

In 1924, to reduce the costs of operations, Utah Copper installed rotary car dumpers and electric switching locomotives at the mills.

Modern facilities are more likely to unload the cars immediately (say with rotary car dumpers) and store the coal in piles until the ship is loaded.

A rotary car dumper or wagon tippler (UK) is a mechanism used for unloading certain railroad cars such as hopper cars, gondolas or lorries (tipplers, UK).

Recently in North America the open hopper car has been in a terminal decline due to the advent of the rotary car dumper (which simply inverts the car to unload it, and has become the preferred unloading technology).

The AAR TypeF TightLock coupler is a Janney automatic coupler typically used on North American gondola cars that go through rotary car dumpers as well as on some tank cars.

Rotary car dumpers simply invert the car to unload it, and have become the preferred unloading technology, especially in North America; they permit the use of simpler, tougher, and more compact (because sloping ends are not required) gondola cars instead of hoppers.

However, since these cars do not have hatches for unloading the products shipped in them, railroads must use rotary car dumpers (mechanisms that hold a car against a short section of track as the car and track are slowly rotated upside down to empty the car) or other means to empty them.