One of the more difficult achievements players can complete during the campaign of Call of Duty: Modern Warfare 3 requires them to use expert timing to destroy a reinforcement helicopter with a mortar strike while it is in the air. Due to the delay in the action effect of the mortars and the fact that the helicopters will quickly dodge a called strike, players will have to use creativity and superb timing to claim this trophy. Players can find success by attempting this challenge on the mission Reactor.