Special VFR (SVFR) flight. A VFR flight cleared by air traffic control to operate within a control zone in meteorological conditions below VMC.

When the weather conditions are below the VMC minima, the pilot is able to ask for a clearance from the ATC to fly VFR within a control zone. This flight will be a special VFR flight. In order to be allowed to fly special VFR, the following limitations should apply for aeroplanes:

• Flight visibility not less than 1.5 km.
• Ground visibility not less than 1.5 km.
• Ceiling not less than 600 ft.
• Flying clear of any clouds.
• Having visual contact with the ground surface.

SERA.5010 (Standard European Rules of the Air) - Special VFR in control zones

Special VFR flights may be authorised to operate within a control zone, subject to an ATC clearance. Except when otherwise permitted by the competent authority for helicopters in special cases such as, but not limited to, police, medical, search and rescue operations and firefighting flights, the following additional conditions shall apply:

(a) such special VFR flights may be conducted during day only, unless otherwise permitted by the competent authority;

(b) by the pilot:

(1) clear of cloud and with the surface in sight;
(2) the flight visibility is not less than 1 500 m or, for helicopters, not less than 800 m;
(3) fly at a speed of 140 kts IAS or less to give adequate opportunity to observe other traffic and any obstacles in time to avoid a collision; and

(c) an air traffic control unit shall not issue a special VFR clearance to aircraft to take off or land at an aerodrome within a control zone, or enter the aerodrome traffic circuit within a control zone, when the reported meteorological conditions at that aerodrome are below the following minima:

(1) the ground visibility is less than 1 500 m or, for helicopters, less than 800 m;
(2) the ceiling is less than 180 m (600 ft).