TOBT Process

TOBT (Target Off-Block Time)


The TOBT is a point in time to be monitored and confirmed by the airline/handling agent at which the ground handling process is concluded, all aircraft doors are closed, all passenger boarding bridges have been removed from the aircraft and thus start-up approval and push-back/taxi clearance can be received.

All ground handling processes, except push-back and de-icing, are based on the TOBT.

TOBT = forecast of "Aircraft ready"



Who sets the TOBT?
The person responsible for TOBT (as defined by Aircraft Operator, e.g. handling agent)

What has to be done?

Management of TOBT (entry, update and if necessary deletion)

When does it have to be done?

The earliest time to enter the TOBT is 90 minutes prior to EOBT.
Prerequisite: The Flight Plan data coherency check (Milestone no.1) was executed successfully.


Determining Factors


  • A TOBT has to be available for all flights
  • During the final approach phase (at ELDT -30min) a TOBT for the linked outbound flight is generated automatically
  • The earliest time for the generation of a TOBT is: EOBT -90 minutes
  • The earliest possible input of a TOBT (before automatic generation) is EOBT-90 min. A manually set TOBT will never be overwritten by an automatically generated TOBT
  • The TOBT shall not be earlier than the EOBT - 10 minutes
  • If the TOBT cannot be kept it has to be updated or deleted
  • The updated TOBT has to differ by +/- 5 minutes from the previous one
  • The TOBT may be changed as often as needed until the publication of the TSAT. After this it may be changed up to three times, thereafter it has to be deleted and a new TOBT may be entered