What happened
On the morning of April 11, 1980, personnel at La Joya Air Base in the Arequipa region noticed a balloon-like object hovering over the airfield in restricted airspace. Because the base had Soviet equipment and espionage was feared, the command sent up an Su-22 fighter piloted by Oscar Santa María Huertas. The pilot opened fire with his cannon, but the rounds had no effect on the object. The object, which up close was shaped like a light bulb with a dome, abruptly changed position every time the pilot approached, and finally climbed to an altitude of more than 19,000 meters. The pilot began running low on fuel and had to return. The event is described in a U.S. military intelligence cable from June 1980.
Witnesses
Pilot Oscar Santa María Huertas and personnel at La Joya Air Base.
Explanations and hypotheses
The Peruvian Air Force did not announce an official explanation. Skeptics suggest a stratospheric or spy balloon, which would explain the climb but not the abrupt changes in position described by the pilot. Santa María Huertas spoke publicly about the event, including in 2007 at a conference at the National Press Club in Washington. The details of his account, including the number of rounds fired, vary from source to source, however.
Unexplained There is no convincing explanation.