This achievement can be kind of tricky. Start by making a banshee follow you into the tunnels all the way to the end. Make sure to kill your companions otherwise they might blow it up. Shoot the wings otherwise it won't fit. Once out fly to the location of the scarab gun located on top of the bridge.
I recommend doing this achievement with the GOOOAAAAALLLL! achievement.
Link to GOOOAAAAALLLL! achievement :[ Ссылка ]
