GTA 5: how to steal and fly Jumbo [airliners]
And yes, it is possible to steal those too. The huge Jumbo airliners that fly through the skies of Los Santos as we play can be stolen and flown like any other GTA 5 plane.
How GTA 5 Passenger Planes Are Stolen
In essence, the procedure is identical to that which allows you to steal any machine in the game. Then go to the airport in the south of the city (the airport icon will appear after the first missions with Trevor). Enter through the gate in the runway area, it is located right next to the steps from where you can start the flight school lessons.
Hit the runway with a car or truck and make sure you land on the wheels of an airliner that is about to take off. This way you should stop the plane, so get out of the car and approach the Jumbo to get on. Alternatively, you can also take those parked on the track. Good fun.
Here are a couple of videos that show you how
Grand Theft AEREO V