The button "LEVEL 1" indicates a lo

The button "LEVEL 1" indicates a low precision is required to maintain the refueling position. This is the default option and is very useful if you are refueling from any aircraft other than the KC-135. If you are refueling from the KC-135 or if you are very good at flying formation, you can change that to "LEVEL 2", which allows for much smaller deviations from the proper position. The button "MANUAL" indicates that you need to manually select the aircraft you want to refuel from the list. You can change that to "AUTO" in which case the closest aircraft is automatically selected. The button "REFUEL ON" is the master button which enables the refueling process. If you switch it to "REFUEL OFF", the fuel level indication will disappear from your screen and you can use the "TRAFFIC INFO" window as a radar. You can change the filter for the aircraft list from "ALL" to "AIR" or "GRND" in order to see only air or ground targets.