This achievement can be a pain to get. Purely because I found a glitch where I finished chapter 2 with the starting ship and I could no longer select the ship to use or upgrade even though it was visible on my screen.
So, if you are past this point in the game just finish the lame story to to destroy the ipod powered nazi ship. Reload chapter 2 using the starting ship and collect as much salvage as you can. Make sure to finish chapter 2 in the Korean fighter. Then continue as normal to upgrade this ship.
In short, finish chapter 2 in the Korean fighter.
The achievement itself to unlock is not glitchy, it's the game that is a glitchy mess.