Elon Musk and Grimes named their newborn baby after this short-lived CIA spy plane able to fly over 2,000 mph

• Tech billionaire Elon Musk and his partner Grimes, a musician, named their newborn baby, at least in part, after the A-12 spy plane built for the CIA during the Cold War.
• The baby boy's name is X Æ A-12, and Grimes said on Twitter that the A-12 stands for the predecessor to her and Musk's favorite aircraft, the SR-71 Blackbird.
• The A-12, which could fly at Mach 3 at 90,000 feet, was only operational for a few years before it was retired and replaced by the famous SR-71.
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Tesla and SpaceX founder Elon Musk's partner Grimes, a pop singer, has given birth to a baby boy, and the child's name is unconventional to say the least. The couple named their son, at least in part, after a CIA spy plane.

The name they gave the newborn is X Æ A-12, a name decidedly as confusing to pronounce as it is difficult to decipher its meaning. Fortunately, the boy's mother broke down the name in a tweet.

Musk replied to Grimes' tweet, clarifying that their favorite aircraft is the SR-71 Blackbird, the predecessor of which was the CIA's short-lived A-12 spy plane.

In the mid-1950s, the CIA began looking at a successor to the U-2 spy plane, desiring a difficult-to-detect aircraft that could fly at incredible speeds at high altitudes.

The reconnaissance plane also needed to be able to skirt missiles and interceptors.

The A-12 was the twelfth in a series of designs under the code name "Archangel" developed by aviation engineering legend Clarence "Kelly" Johnson and Lockheed's Skunk Works that ultimately won a CIA contract for Project OXCART in 1959.

America's first "stealth" aircraft was declared fully operational in 1965, according to the CIA. It could fly at sustained speeds in excess of 2,200 mph (Mach 3) at 90,000 feet, an unofficial record that technically remains unbroken for piloted jet aircraft.

The aircraft's first and only reconnaissance operation took place between May 1967 and May 1968, during which time it flew 29 missions over East Asia as part of operation BLACK SHIELD, carrying out surveillance of military activities in Vietnam.

The A-12, which was designed during the height of the Cold War, never conducted operations over the Soviet Union or its satellite states as initially intended.

The A-12 was ultimately replaced by the Air Force's two-seated SR-71 Blackbird, an aircraft designed by Lockheed that built on many of the engineering breakthroughs of its predecessor.

While the A-12 documented a speed of 2,208 mph at 90,000 feet in 1965, the SR-71 holds the official speed record for a piloted operational jet aircraft.

The latter set the record in 1976 with a speed of 2,193. It also set the official altitude record at 85,069 feet, according to the CIA.

As it was deemed unnecessary to maintain separate fleets of similar aircraft, the A-12 was retired in 1968 at the direction of the president. The SR-71 Blackbird was deactivated in the late 1980s and ultimately terminated in the late 1990s.