TrimStab, when the Chinooks were new they did a drop off of some guy at I think Speke, as it was unauthorised and they knew they would get stung for landing fees, they circumvented it by hover taxying up to the apron, the guy jumped out and they threw his bag down to him, they then hover taxied out and departed, sure enough a bill arrived and they refused to pay it stating they never landed at Speke.... They had to after checking concur
