Node:Gradual Loading, Next:Disaster selection, Previous:Move Error Popups, Up:The Patches
Normally, when a consist arrives at a station, all of its cargo is unloaded and the new cargo is loaded instantly, and then it sits there waiting for a few seconds.
With this switch, all loading and unloading processes are changed so that they occur gradually. Instead of loading or unloading everything at once, only 5-10 units of cargo per vehicle are loaded or unloaded at a time. This means that you can watch your train window and see how the cargo gets loaded or unloaded. This is especially useful for the new ship graphics, which are capable of showing different loading states. Without this switch, you'll probably never see how the ships are being loaded or unloaded.
Another useful property of this switch is that trains can have some carriages being loaded while others are still being unloaded. This can sometimes speed up the loading and unloading in a train station. Also, a vehicle will not leave the station while there is still cargo available for loading, no matter what the setting of the "full load" option is. This is true even if the new cargo appears when the vehicle is already being loaded, the new cargo will just be loaded as well, until the consist is full or no more cargo is available for loading.
Note that the gradual loading switch requires that the loadtime switch is active too, and will always activate it if you haven't already done so. It also changes the loading time by making it cargo type specific, meaning that one type of cargo can be done with loading but another still has more cargo to be loaded or unloaded. Because of this, sometimes train can take a bit longer to load if you have an uneven number of carriages for each cargo type.
Normally, gradual loading loads or unloads all wagons of a train at the same time. This may have some side effects if the train has multiple destinations, for example if it loads coal from several stations. In that case, the coal that's added at the last station causes the entire load to be considered to be from that station. This means you'll get less money than you should have. You can use the "miscmods" switch to choose to have the wagons loaded separately. See Miscellaneous Modifications for more details.