What is the minimum visibility required for an aeroplane to depart from an aerodrome within a control zone during special VFR?

For an aeroplane to depart from an aerodrome within a control zone under Special VFR (Visual Flight Rules), the minimum visibility required is indeed 1 mile. Special VFR allows pilots to operate in controlled airspace under certain conditions that are below the standard VFR weather minimums. This regulation is crucial for enhancing safety by ensuring that pilots maintain visual reference to the ground while still providing some flexibility for operations when weather conditions are less than ideal.

In scenarios involving Special VFR, pilots must also receive clearance from air traffic control before departing. This clearance is essential as it ensures that ATC can provide the necessary instructions to maintain safe separation from other aircraft. Therefore, the 1 mile visibility requirement strikes a balance between allowing pilots the opportunity to operate in tighter weather conditions while still emphasizing the need for visibility, which is critical for visual navigation and avoiding obstacles.

Overall, understanding these requirements helps pilots make informed decisions when operating in varying weather conditions and highlights the importance of adherence to regulations for safety in aviation.