One thing to note with all of these challenges where you need to fill a meter is to not try and do the stunt until you’re told or it won’t count. The game is very particular about that so try not to get too far ahead.
In this challenge, Jackson will teach you how to fly the plane on its side. You must maintain altitude as you fly so you must control the rudders at the same time. When prompted, roll the plane on its side in whichever direction you want. If you roll to the right, use the left rudder to control the altitude and vice versa if you went left. You will know when you’re far enough over because the meter will start to fill up.
When prompted, do the same thing on the other side and don’t forget to level up after you’ve finished to complete the challenge and get the Gold.