The most accurate, up to date information for better planning and more informed decision making.
AOP is the platform we use at LHR to allow airport stakeholders (the airport operator, aircraft operators/ground handlers, ATC and the Network Operations Manager at EuroControl) to show and share information on both the progress and plans for arrivals, departures and towed movements around the airport. By openly sharing information we can work together more efficiently and transparently and maximise the use of both the runways and preferred stands.
One of the main outputs of the AOP process is to provide a greater degree of accuracy to the EuroControl Network Manager through publishing Target Take Off Times for departures from LHR. The Network Manager can use this information to improve en route and sector planning of the European ATM Network. The ultimate benefit for LHR is that using the latest and most accurate information allows the Network Manager to plan and prioritise in advance, allowing improvements in slot delays to LHR departures. Slots are given to departures if there is an excess in demand for traffic to a given outstation or in the en route airspace that a flight is planned to operate in. They are referred to as Calculated Take off Time (CTOT) and in effect provide a guaranteed runway slot to that aircraft, which may be some time after the aircraft is scheduled to depart or is ready to depart. The fewer CTOTs that we have at LHR the greater flexibility the Air Traffic Controllers have in delivering the flow of traffic to our busy runway(s).
At thirty minutes before departure we use the Target Off-Blocks Time (TOBT) to create a 'virtual place' for the aircraft on the runway and provide visibility of an expected Target Start-up Approval Time (TSAT). We also use your TOBT to calculate a Target Take-Off Time (TTOT) that is communicated to the Network Manager. This TTOT is used in the management of European airspace.
Heathrow will be transitioning from our current AOP platform to the new AOP platform (AIRHART) during November 2026. The existing AOP will remain available and unaffected during the transition.
Target Off-Blocks Time (TOBT) must be updated to an accuracy of +/- 5 minutes. If your TOBT is changing please take a minute to think through the reason the time is changing and decide on a new time that is realistic. Late, small, and repeated incremental changes are to be avoided as this creeping delay creates a phantom requirement for a runway place. Please find below some key points
Estimated Off-Blocks Time (EOBT) must be aligned to within +/-10 minutes of the TOBT. This is to support Eurocontrol with ensuring flight plan times (EOBTs) are kept aligned with flow control measures which are influenced by TOBTs.
Airlines are reminded of the need to comply with flight planning behaviours as detailed in the Eurocontrol ATFCM Users Manual, particularly around Late Filers and Late Updaters, as quoted below:
8.1.5 Late filing
FPLs sent to the IFPS less than 3 hours before the EOBT will render those flights as “late filer”. These flights may be penalised during the slot allocation process. In the flight status column (STA) of the flight list in CHMI / NOP Portal these flights can be identified with a “LF”.
8.1.6 Late updating
Modifications to the FPL (DLA / CHG) sent less than 2 hours before EOBT will cause the flights to be considered as “late updater” if the update changes the profile calculation. In the flight status column (STA) of the flight list in CHMI / NOP Portal these flights can be identified with a “LU”.
Pilots should call Delivery at TOBT +/-5 minutes. If they become aware of any reason why they may be unable to meet the TOBT (+/- 5 mins) they should advise the ground handler and provide a new, realistic TOBT.
After completing online registration, external stakeholders should contact the IT Service Desk for any further assistance.
Call 020 8745 5355If your query is urgent and may affect the timely operation of a flight please call the Aircraft Operations Duty Manager at any time 24 hours a day.
Call 07525 825585
