The actress - who raises six children with partner Brad Pitt - took pilot lessons after realising how much her eldest child, Maddox, now eight, enjoyed watching planes go by.
She explained: "When Maddox was one and a half, we used to go to the airfield, have lunch and watch the planes. And it dawned on me: I could fly. So I promised him I would fly by his second birthday."
The -Salt- star admits she loves boarding a plane alone as it is the only time she gets the solitude she craves.
She added to Vanity Fair magazine: "it-s the only place I-m completely alone - up in the air, detached from everything.
"Brad loves the technical aspects. He loves the checks, loves all the maths. I-m terrible at the maths, but I love that I can go anywhere and have that freedom. He-s more patient. I tend to drive it to the ground."