The chick, a star of this year's BBC Springwatch, was rescued a month ago, when it was feared she had fallen 30ft from the nest.
Webcam footage of the nest, in a secret location in Forestry Commission Scotland land on Mull, later revealed she had been pushed out by a rogue eagle.
When the nest was found to be empty once more Scotland's top sea eagle expert Dave Sexton feared for the chick's life - only to discoverfind she had successfully made her maiden flight.
Mr Sexton, RSPB officer for Mull, said: "When I saw the nest empty again on Thursday and couldn't hear her calling I dreaded going in. I was worried I might find her dead under the nest, as has happened with other chicks.
"There was no sign of her and I couldn't hear her either which was unusual, but I eventually found her sitting on top of a tree stump, surveying the view around her.
Her father was watching from nearby.
"Then there she was soaring in the warm breeze looking like a proper eagle. It's for moments like this that I do this job."