How many U-2 spy planes were built?

The Lockheed U-2 'Dragon Lady' spy plane is famously one of the oldest aircraft types in service with theUnited States Air ...
The National Interest on MSN

Why the U-2 Dragon Lady Spy Plane Is an Astonishing Feat of Engineering

The U-2’s ability to reach 70,000 feet—an altitude that most modern fighter jets cannot match—came about after a series of remarkable design innovations.
Jalopnik

The U-2 Spy Plane May Be Old, But It's Celebrating Its 70th Birthday By Setting New Records

Not many 70-year-olds can set endurance or distance records. But the U-2 spy plane did both on July 31. It took off from Beale Air Force Base in California and flew a zig-zag lap around the ...
Space on MSN

U-2 spy plane captured stunning image of Chinese surveillance balloon

Footage of a United States U-2 spy plane that captured imagery of the Chinese surveillance balloon that flew over the ...