Here is the full list of all 24 Air Conflicts: Secret Wars achievements worth 1,000 gamerscore.
Complete Chapter I
Complete Chapter V
Complete Chapter III
Complete Chapter VI
Complete Chapter II
Complete Chapter IV
Complete Chapter VII
All missions completed
Unlock all planes in single player campaign
Shoot down 100 aircraft in Campaign Game
Destroy 100 ground units in Campaign Game
Place in top half in Deathmatch with at least 6 players
Place first in Deathmatch with at least 6 players
Kill 100 players in multiplayer
Play 50 multiplayer matches
Kill 5 players in multiplayer without dying
Kill 10 players in multiplayer without dying
Win 5 multiplayer matches with RAF team
Win 5 multiplayer matches with Red Air Force team
Win 5 multiplayer matches with Luftwaffe team
Win 5 multiplayer matches with any Great War Team
Perform long range Rocket Kill in Multiplayer
Perform extra long range Rocket Kill in Multiplayer
Shot down enemy aircraft with a rocket at great range in single player