Blown Out of the Sky

From Halopedia, the Halo wiki

Blown Out of the Sky is an achievement in Halo: The Master Chief Collection. It is unlocked by blowing up a Banshee or Hornet in mid-flight, with a Rocket Launcher in Halo 2: Anniversary multiplayer. The achievement is worth 10 Gamerscore and can be unlocked in both matchmaking and custom games.