Jacobsen writes, "Ed Lovick, at Skunk Works in the mid-1960s, with the waveguide, as he works to reduce the radar cross section for the A-12 (aircraft) to meet the CIA's demands."
The Archangel-12 (A-12) spy plane, intended to replace the U-2, was designed so as to reduce its radar cross section an astonishing 90 percent. Proof-of-concept tests were conducted at Area 51 beginning in 1959, with full-scale mockups built and elevated onto 50-foot pylons to test their radar-evasion effectiveness.
In 1960 the CIA authorized construction of twelve planes, capable of reaching Mach 3.2 (or .57 miles per second), with a range of 4,120 nautical miles and capable of reaching an altitude of 97,000 feet. The A-12 was code-named Oxcart. Roswell UFO, "Area 51" controversies: Nazi link?Annie Jacobsen's "Area 51"