On mission 6.2 you have to listen to Montgomery's conversation without being hit.
When you start the mission go to the waiter on the phone and annoy him until you get a three button combo. Once he walks out take a picture of the reservation chart on the podium. Now go into the main restaurant and go straight ahead, you'll see the next picture marker you need. Once you take the picture go to the old man and annoy him until you get the button combo. Now Montgomery and his guest will be outside. Hit the first wind tunnel, then the second and now you'll be at a spot to take the picture. Take the picture then get into the third wind tunnel. Once you land you're golden. After the level you'll get the achievement.
You can NOT be heard by Montgomery in this level! That counts as being hit.