 Commercial operations are remunerated activities which fall within the ICAO definition of CAT . Some are , however , closely aligned to , and considered part of , the GA sector . Public transport operations are non @-@ scheduled , on @-@ demand services flying between points specified by the customer , providing a more flexible service than airline travel . Air taxi operations offer charter services for third parties , and business or corporate aviation uses company @-@ owned aircraft to transport employees and clients . Aircraft used in these operations include business jets , helicopters , and twin piston @-@ engine aeroplanes carrying between six and ten people . An example of this type of operation is the transport by helicopter of spectators to the British Formula One grand prix at Silverstone . This involves so many flights that , according to Cranfield Aviation Services , on race day the heliport is temporarily the world 's busiest airport . Aerial work is a small but important component of the commercial GA sector , characterised in its simplest form as remunerated non @-@ transport activities , such as surveying , crop spraying , and emergency services work ( air ambulance and police ) . 
 Commercial operations are remunerated activities which fall within the ICAO definition of CAT . Some <a href='drop_aux' title='1'><mark>are</mark></a>, however , closely aligned to , and considered part of , the GA sector . Public transport operations <a href='drop_aux' title='2'><mark>are</mark></a>non @-@ scheduled , on @-@ demand services flying between points specified by the customer , providing a more flexible service than airline travel . Air taxi operations offer charter services for third parties , and business or corporate aviation <a href='uninflect' title='3'><mark>uses</mark></a> company @-@ owned aircraft to transport employees and clients . Aircraft used in these operations include business jets , helicopters , and twin piston @-@ engine aeroplanes carrying between six and ten people . An example of this type of operation <a href='drop_aux' title='4'><mark>is</mark></a>the transport by helicopter of spectators to the British Formula One grand prix at Silverstone . This <a href='uninflect' title='5'><mark>involves</mark></a> so many flights <a href='null_relcl' title='6'><mark>that</mark></a>, according to Cranfield Aviation Services , on race day the heliport <a href='drop_aux' title='7'><mark>is</mark></a>temporarily the world <a href='null_genetive' title='8'><mark>'s</mark></a>busiest airport . Aerial work <a href='drop_aux' title='9'><mark>is</mark></a>a small but important component of the commercial GA sector , characterised in its simplest form as remunerated non @-@ transport activities , such as surveying , crop spraying , and emergency services work ( air ambulance and police ) . 
Commercial operations r remunerated activities which fall within the ICAO definition of CAT . sum , however , closely aligned to , and considered part of , da GA sector . Public transport operations non @-@ scheduled , on @-@ demand services flying between points specified by tdacustomer , providing a more flexible service den airline travel . Air taxi operations offer charter services fir third parties , and bizness or corporate aviation use company @-@ owned aircraft to transport employees and clients . Aircraft used in these operations include bbiznessjets , helicopters , and twin piston @-@ engine aeroplanes carrying between six and ten people . An example of this type of operation the transport by helicopter of spectators to thdaritish Formula One grand prix at Silverstone . dis involve so many flights , according to Cranfield Aviation Services , on race day thedaliport temporarily the dald  busiest airport . Aerial work a small but important component of the cdaercial GA sector , characterised in its simplest form as remunerated non @-@ transport activities , such as surveying , crop spraying , and emergency services wrk ( air ambulance and police ) .