Take Flight (Generation Icarus #2) - J. L. Pawley

The Flight is recovering in a remote mountain hideaway. They think they're safe, but they couldn't be more wrong. When Evolutionary Corp mercenaries in helicopters hunt them down, only Condor and Kestrel manage to escape. With nowhere else to turn and desperate for help to save their friends, the two flee across the country to the jubilant Angelists. Meanwhile, a nightmare unfolds for the imprisoned teenage Icari. A shocking bond is revealed which changes everything. Pushed to the limits of endurance, somehow they must survive the most dangerous place they can imagine. Somehow, they must fly free.