Spy and stealth planes—some with bizarre, bat-shaped wings, others with triangular silhouettes that imply otherworldly designs—have long generated UFO sightings and lore. And official denials feed rumors that the government isn’t telling us about alien ships. The CIA estimates that over half of the UFOs reported from the ’50s through the ’60s were U-2 and SR-71 spy planes. At the time, the Air Force misled the public and the media to protect these Cold War programs; it’s possible the government’s responses to current sightings of classified craft—whether manned or remotely operated—are equally evasive. The result is an ongoing source of UFO reports and conspiracy theories

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