I souped up a beefy jeep free of charge (I bought Los Santos Customs) and stormed in there, took the jet and flew out then landed it at the hanger.
With Trevor, another easy way is to get high above the place you want to land, jump out of your Heli/Blimp and and skydive down, don't pull the Parachute. Instead, activate Trevors special ability as you're about to hit the ground and you take minimal damage.