General aviation in the United Kingdom General aviation in the United Kingdom has been defined as a civil aircraft operation other than a commercial air transport flight operating to a schedule or military aviation . Although the International Civil Aviation Organization ( ICAO ) excludes any form of remunerated aviation from its definition , some commercial operations are often included within the scope of general aviation ( GA ) in the UK . The sector operates business jets , rotorcraft , piston and jet @-@ engined fixed @-@ wing aircraft , gliders of all descriptions , and lighter than air craft . Public transport operations include business ( or corporate ) aviation and air taxi services , and account for nearly half of the economic contribution made by the sector . Other commercial GA activities are aerial work , such as surveying and air ambulances , and flight training , which plays an important role in the supply of pilots to the commercial air transport ( CAT ) industry . Private flying is conducted for personal transport and recreation . It includes a strong vintage aircraft movement , and encompasses a range of air sports , such as racing , aerobatics , and parachuting , at which British teams and individuals have succeeded in international competition . Of the 21 @,@ 000 civil aircraft registered in the UK , 96 per cent are engaged in GA operations , and annually the GA fleet accounts for between 1 @.@ 25 and 1 @.@ 35 million hours flown . The single most common class of aircraft is the fixed @-@ wing light aircraft associated with traditional GA , but the main area of growth over the last 20 years has been in the use of more affordable aircraft , such as microlights , amateur built aeroplanes , and smaller helicopters . There are 28 @,@ 000 Private Pilot Licence holders , and 10 @,@ 000 certified glider pilots . Some of the 19 @,@ 000 pilots who hold professional licences are also engaged in GA activities . Although GA operates from more than 1 @,@ 800 aerodromes and landing sites , ranging in size from large regional airports to farm strips , over 80 per cent of GA activity is conducted at 134 of the larger aerodromes . The GA industry , which is around 7 per cent the size of its CAT cousin , employs 12 @,@ 000 people , and contributes £ 1 @.@ 4 billion to the UK economy .GA is regulated by the Civil Aviation Authority ( CAA ) , although regulatory powers are being increasingly transferred to the European Aviation Safety Agency ( EASA ) . The main focus is on standards of airworthiness and pilot licensing , and the objective is to promote high standards of safety . At the lighter end of the GA spectrum some regulatory authority is devolved to representative bodies , and gliding is in transition from a self @-@ regulatory model to more formal governance by EASA . Airspace regulation necessary to protect an increasing number of CAT operations has reduced the area in which GA flights can be freely conducted . The growth in CAT is also making access to larger airports more difficult for the GA sector , and smaller aerodromes are vulnerable to closure and re @-@ development for more profitable uses . The UK planning system has no remit to consider the national significance of GA public transport operations , and generally does not favour the development of smaller aerodromes catering to the GA market . The planning process has become a mechanism for addressing local aerodrome @-@ related environmental issues which , particularly regarding noise , are the main subjects of public criticism levelled at GA .fill in the blank General aviation in the __________________ Kingdom. 
Output:  United