The SR-71 Blackbird was first seen in the Call of Duty: Black Ops teaser trailer. In the game it appears in the campaign level "WMD". In the cockpit of the Blackbird "Big Eye 6," the playable character Mosely is prompted to activate the jet's engines, and then pull back on the stick during take-off. Major Neitsch then uses the SR-71's reconnaissance equipment to guide a squad of four friendly soldiers past enemy patrols in the Ural Mountains. Once this is accomplished, players then takes control of Hudson on the ground hiding from the patrols. Once they go away, the mission continues.

Multiplayer

The radar with the Blackbird in effect. Note the enemies shown as arrows

The Blackbird appears as an 8-killstreak award (7 with Hardline) in multiplayer, and cannot be shot down. It is an advanced radar, giving real-time updates of where enemies are positioned and in which direction they are facing by using red arrows. The Blackbird lasts for 45 seconds after use and takes 3 seconds for it to disappear from the radar, where the icons are still visible but only shows their last location. A Counter-Spy Plane will block a Blackbird, and is the only defense against it. The Blackbird shows all enemy players, even Ghost Pro users. 

Trivia 

• The 1963 flight data of the SR-71 can be found in U.S.D.D. and "Five". The name of a pilot is Sullivan.
• If one looks closely, the SR-71 can be seen in the sky in multiplayer. However, it is very difficult to spot, as it only appears as a flashing blip with a tiny smoke trail.
• There is an SR-71 Blackbird in the middle of Hangar 18.
• Some announcers refer to the killstreak as the SR-71, rather than the Blackbird.