SciFi about Hang Gliding Couriers

Story takes place on a planet that was colonized long ago. Most of the planet is water with chains of islands, sea travel is dangerous because of sea beasties. A courier system has been set up by repurposing the super-light material scavenged from the original colony ship into hang gliders features a female lead who I believe learns the craft from an old courier who's no longer able to fly. Story ended with >!the courier growing old, and instructing the boy taking care of her to spread the story that she went out in a blaze of glory trying to do one last run and plunging her glider into the sea. She then actually passes peacefully in her sleep!<

I think I read this around 2011 but it it could have been as lat as 2014

Edit: Solved already despite me misremembering the ending. It was Windhaven by George R R Martin and Lisa Tuttle