actualTime
ATOT (Actual Take-Off Time): the time that an aircraft takes off from the runway (Equivalent to ATC ATD - Actual Time of Departure, ACARS=OFF).
calculatedTime
CTOT (Calculated Take Off Time): a time calculated and issued by the appropriate Central Management unit, as a result of tactical slot allocation, at which a flight is expected to become airborne. (ICAO Doc 7030/4 - EUR, Table 7).
targetTime
Inherited from TakeOff. See section 7.33.