C-DRONE GUIDE · 17 AUGUST 2026
Drone Mission Inside an Airport CTR: Who to Contact, What Delay, What Protocol
A warehouse to inspect, a construction site to track, an industrial facility to map, a corporate shoot to film: none of that matters once the address falls inside an airport's CTR. Around most large French cities and many regional aerodromes, this control zone covers a radius of several kilometres and requires prior authorization, whatever the client or the planned service. Here is who to contact, in what order, what actually changes for the flight, and how to plan for the delay so a construction or filming schedule doesn't end up hostage to an administrative reply.
Published on 17 August 2026, reviewed on 18 August 2026 — regulations in force as of August 2026.
How to know whether a site falls inside a CTR
A CTR (control zone) is the controlled airspace surrounding an aerodrome equipped with an air traffic service, from ground level up to a defined ceiling. It shows up directly on the Géoportail UAS restriction map: clicking the zone displays the maximum authorized height and the restriction's reference. The exact radius and the heights that apply vary from one aerodrome to another — typically 0 m within 2.5 km of the runway, then 30, 50 and 100 m further out — and should be confirmed on the relevant aerodrome's VAC chart before taking any step.
Many professionals discover the constraint late, while preparing a flight for a job that has nothing to do with aviation: a logistics roof audit, a construction survey, a corporate film about an industrial site. Around a mid-sized town, it is not unusual for an entire business park to sit under a CTR without anyone at the client company realising it. The reflex to build in is simple: check the map when the quote is drawn up, not the day before the flight — a point we cover with a full worked example in our guide to reading the Géoportail map.
Who authorizes the flight, and in what order
Flying a drone inside a CTR is prohibited by default: prior agreement is required, requested in a set order. First, the organisation providing air traffic services — the tower, operated by the DSNA (France's air navigation services directorate) — at aerodromes that have one. Failing that, the provider of the flight information service (AFIS), which covers most regional and flying-club aerodromes: usually reachable by phone or email, with a shorter turnaround than at a major airport. Failing that too, the aerodrome operator itself, at the smallest airfields.
The request must state the exact location of the flight (GPS coordinates or a precise address), the maximum height planned, and the date and time. A formal written protocol can also be required in two common cases: a beyond-visual-line-of-sight flight (see our guide to BVLOS flight), or a CTR under the authority of the Ministry of the Armed Forces rather than civil aviation — common around former air bases partly converted to civilian use.
What the CTR actually changes for the mission
The first and most systematic effect: the maximum flight height drops, often to 30 m instead of the 120 m allowed in open airspace — plenty for most jobs (roof, façade, ground-level construction site), but a constraint to build into planning for a high-altitude survey or a wide establishing shot. Second effect: the flight slot is often negotiated outside traffic peaks, early morning or evening at a busy aerodrome, which can shift the timing of a job away from what a client expects from a standard service. Third effect: at some aerodromes, the agreement covers a precise window rather than open availability — a last-minute weather delay can therefore mean requesting a new slot rather than simply pushing the flight back a few hours.
Since 2023, some French CTRs have been gradually joining the European U-space framework: coordination there runs, or will run, through an approved U-space service provider (USSP) rather than a direct human contact with the tower. A study published in 2020 in the journal Aerospace by Alarcón, García, Alarcón, Viguria, Martínez, Janisch, Acevedo, Maza and Ollero, carried out under the European SAFEDRONE project, designed and flight-tested procedures for integrating drones into controlled airspace using these digital services (see the study on Google Scholar): a preview of what is today, at most French aerodromes, still a largely manual process.
CTR and populated area: two authorizations that can stack
CTR clearance is a separate process from the prior flight declaration in a populated area filed on AlphaTango for a European standard scenario (STS-01): the first goes to the aeronautical body managing the aerodrome, the second to the préfecture via the DGAC. Around a mid-sized town, it is not unusual for both zones to overlap — a whole town centre covered by a CTR and by populated-area status at the same time — which means running both processes in parallel rather than one after the other, so the delay does not double. The choice of flight category (open or specific) also stays independent of the CTR: a mission in the open category outside a populated area, but inside a CTR, only needs the aeronautical clearance, with no préfecture declaration.
As with any professional job, the operator must be registered on AlphaTango and covered by professional third-party liability insurance — a serious insurer will often ask, for a site inside a CTR, for proof of the clearance obtained before covering the mission.
Delays to plan for and the impact on a client's schedule
At a secondary aerodrome or a flying club covered by AFIS, a straightforward request can go through within a few working days. At a major airport with dense commercial traffic, expect several weeks instead, particularly if a formal written protocol is required — the delay is neither guaranteed nor standardised, and depends on how busy the tower is and how complex the request is. For a client on a tight schedule (a unit going up for lease, a construction milestone, a fixed filming date), this delay needs to go into the quote from the first contact, not be discovered the week of the flight.
Without that prior agreement, the flight is simply illegal, whatever the service planned: our guide to drone penalties and inspections in France details the scale of fines and sentences that apply to an unauthorized flight over controlled airspace — a risk neither the remote pilot nor the client commissioning the work has any reason to take just to save a few days. This administrative delay, though, has no direct impact on the price of the service itself: it is budgeted as lead time, not as a surcharge.
Frequently asked questions about drone flight in a CTR
Does the CTR clearance cost the client anything? No, the request to the tower, the AFIS or the operator is free; it is the lead time that needs planning for, not a billed surcharge.
Does a clearance obtained once cover every later flight at the same spot? Rarely: most agreements cover a specific date and time slot. An operator running recurring missions at the same site can, however, negotiate a standing protocol with the aerodrome.
What happens if weather forces a delay? Depending on the aerodrome, pushing the flight back a few hours the same day is sometimes possible with a simple phone call; moving it to another day usually means filing a new request.
Does the CTR also apply to drones under 250 g? Yes: the restriction concerns the airspace, not the aircraft's weight — no drone is exempt from prior clearance inside a CTR.