Definition

Calculated Take Off Time (CTOT) - The time provided by the Central Flow Management Unit (CFMU), taking into account the European Civil Aviation Conference (ECAC) ATC flow situation, that an aircraft has been calculated to take off. The CTOT, also known as the ATFM ( Air Traffic Flow Management) slot, has a tolerance of – 5 to +10 minutes

Further Reading

EUROCONTROL

• ATFCM Users Manual - Flow management (CFMU)
• Flight Plan and ATFCM adherence for the safe and optimum flow of air traffic