You need to get the ship as far to the right of the track as possible in order to gain the height to barrel roll onto the overpass. Give left air brake a quick press and pitch up, quickly input the BR command and it should land. Some people prefer to do a left side shift to maintain altitude but not everyone does.

It will take a lot of practice to get the trophy, I know it took me 459 laps to achieve (yes I counted every lap)