 The number of aerodromes that support GA in the UK is difficult to establish with certainty . <unk> 2008 United Kingdom Flight Guide lists 355 , and the <unk> Flight Equipment UK <unk> Flight Guide 2008 lists nearly 500 . <unk> Farm ' <unk> ' and Private <unk> Flight Guide lists more than 300 landing sites . The GASAR study estimates 1 @,@ 100 formal flying sites in England alone , a figure which includes 400 sites known to planning authorities but not included in flight guides . It estimates another <unk> informal sites known only to land owners , customs , and members of the enthusiast group Air @-@ Britain . 
