To minimise disturbance pilots are instructed to avoid large centres of population, towns with over 10,000 inhabitants. Fixed wing aircraft are to avoid overflight of these areas below 2,000 feet minimum separation distance (MSD). Light aircraft and rotary wing are to avoid overflights below 1,000 feet MSD. Aircraft conducting authorised flypasts may overfly the area at 1,000 feet MSD if approved by MOD.