CRT is Calculated Rig Time. Think of it as a line rig. Whether your line starts with an operating flight out of your base, a DH from your base or sitting reserve in your base your CRT starts when you go on duty and is paid till when your schedule shows you getting off duty in your base. With the carve outs if you call in sick or have training in the middle of a trip. My block time beat the rig one month last year. So I figured I was paid $48.25 an hour from when the schedule showed me leaving base till when it showed me back.