Revealed: How Area 51 Hid Secret Craft

No word yet on alien starships, but now that many Cold War-era Area 51 documents have been declassified, veterans of the secret U.S. base are revealing some of the clever—and surprisingly low-tech—ways they hid futuristic prototypes from prying eyes.

https://www.nationalgeographic.com/science/article/110520-area-51-secret-hid-craft-base-declassified-a-12-plane