Upon completing the first chapter, all other chapters will be unlocked. Go to World 3, The Danger Above. Complete the first 3 levels of chapter 6. On Chapter 6, level 4, you will see the Boomerang Bird in a cage. Aim for the triangle wooden block with your Speeder Bird. Sometimes you won't blow up the TNT, fire another and you should hit the TNT and kill the rest of the pigs, still giving you the 3 stars for the level. Once you load the next level, achievement unlocked.
Below is a 3 star tutorial uploaded by iAddict00, I take no credit for the video.