Short answer: an airline’s Operations Control Centre (OCC) runs 24 hours a day, every day of the year. During a shift, the Flight Operations Officer (FOO) takes the handover, prepares flight plans, manages slots with EUROCONTROL, watches flights in the air and reacts to delays, diversions and technical faults. The shift described here follows the duties set out by ANAC and EASA and what airlines ask for in their job ads.
Why does the OCC never close?
Because there is always a flight departing or in the air. European air operations rules require every operator to maintain a system of operational control over all its flights, as EASA sets out in ORO.GEN.110. That is why FOO job ads in Lisbon mention ‘24/7/365‘.
How does the shift begin?
With the handover. EASA guidance (GM2 ORO.GEN.110(f)) says the incoming FOO should be briefed on:
- weather charts and reports;
- NOTAMs in force;
- operational restrictions;
- flights in the air, and flights with a plan issued that have not yet departed;
- the forecast flight schedule.
Only then does the FOO take responsibility for the shift’s flights.
What happens before each departure?
The FOO prepares the flight. Annex I of the ANAC regulation describes the tasks at this stage:
- Analyse weather on the route, at the destination and at alternates.
- Check runways, navigation aids and restricted areas.
- Calculate the operational flight plan, the optimal route and fuel for the expected payload.
- Confirm the ATS flight plan has been filed.
- Brief the captain on weather, airports, plan and slot. Captain and FOO both sign the operational flight plan.
Flight plans go to EUROCONTROL’s IFPS system. For flights subject to flow management, they must be filed at least 3 hours before the estimated off-block time, according to the Irish AIP, which publishes the European network rule.
What is a slot and why does it keep the FOO busy?
It is the take-off time EUROCONTROL allocates when there is congestion, called the CTOT. The flight must take off between 5 minutes before and 10 minutes after that time, as SKYbrary explains.
In summer 2026, 21% of flights in Europe were delayed by flow restrictions, according to EUROCONTROL. Each delay forces the FOO to decide: request a better slot, change the route or update the departure time.
At A-CDM airports, the airline or handler also updates the TOBT, the time the aircraft will be ready to leave. EUROCONTROL uses that value to calculate the TSAT, the time the aircraft can request start-up.
And once the aircraft is airborne?
The FOO follows it to arrival. The ANAC regulation calls for constant monitoring, especially over oceanic and desert areas, an up-to-date flight plan and contact with the crew about hazards. If a diversion is needed, the FOO starts the diversion, alert and emergency procedures.
In EASA terms, this is ‘flight watch’: actively tracking the flight to confirm there is no unplanned deviation, diversion or delay.
What tools does an FOO use?
Flight planning systems, weather data, NOTAMs and EUROCONTROL tools. Job ads mention software such as Jeppesen, PPS and Astro, for example at GlobeAir. FOOs also check the MEL, the list of equipment that can be inoperative for the aircraft to fly, as SKYbrary explains.
Who works alongside the FOO?
The OCC brings several roles together. In Lisbon, Hi Fly hires Operations Controllers for disruption management and coordination with maintenance, and Crew Controllers to manage crew rosters. An experienced FOO can move into these roles or into OCC Duty Manager.
How do you prepare for this work?
With an FOO licence, issued by ANAC. IITA’s Flight Operations Officer License (CAA-Certified) is ANAC-certified and delivered by AWA (Aeronautical Web Academy), with a guaranteed internship at an airline. The October cohort starts on 26 October 2026.
The internship is the first contact with real shifts. We explain how it works in this article.
Frequently asked questions
Do FOOs work shifts?
Yes. OCCs run 24 hours a day, with rotating shifts that include nights and weekends.
Does the FOO talk to the pilots?
Yes. They brief the captain before the flight, both sign the operational flight plan, and they stay in contact during the flight.
What is a CTOT?
The take-off time EUROCONTROL allocates when there is congestion. The flight has a window of −5 to +10 minutes.
Do you need a licence to work in an OCC in Portugal?
To work as an FOO, yes: the licence is issued by ANAC. Other OCC roles have different requirements.
Sources
- ANAC, Regulation 614/2018, Annex I, 21 September 2018
- EASA, AMC/GM to Part-ORO
- EUROCONTROL, Special Summer 2026 Flash Briefing, 11 September 2026
- EUROCONTROL, What is A-CDM, 2025
- AirNav Ireland, AIP ENR 1.10, 14 May 2026
- SKYbrary, Calculated Take-off Time and MEL
- Job ads: Hi Fly, GlobeAir, accessed 12 October 2026
