In this task, you will be given a passage to read. A fill in the blank question will be given to you.  Your answer should fit the blank appropriately.

 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. 
 United 