Actual Time of Departure is the time when an airplane is actually taking off. In logistics, ATD can also mean the point in time when a shipment is dispatched. The counterpart to this is Actual Time of Arrival (ATA), describing the time the shipment arrives.While the Estimated Time of Departure (ETD) is a known factor, the Actual Time of Departure can only be specified when the shipment is already on its way. A comparison of ETD and ATD helps to recognize a delay in delivery.