Chorus

This is story related, at the destination you will find the ships which have to be released within a set time from corruption entanglements while under the usual assault of Circle ships. Each ship has about 3 nodes that you have to find and hit with the Storm Rite in quick succession otherwise they reset.

The last part of "the escape" gives you another chance to control a Spirit Class ship.

Note, although it's a simple achievement mine did not pop straight away, even though the "Mission Completed" notification was displayed on screen. It was only next day on starting the game again and hitting "Continue" did this and the other achievements gained in this region.