Before drones and/or Unmanned Aerial Vehicles existed, countries would spy on each other using high altitude aircraft.
The USA had the famous SR-71 Blackbird ; the fastest and highest-flying jet aircraft in the world (to this day), achieving altitudes of over 85,000 feet and reaching speeds of Mach 3.3–that’s more than 3,500 kph (2,100 mph) and almost four times as fast as the average cruising speed of a commercial airliner. It was the perfect aircraft for reconnaissance missions.
Its incredible speed enabled it to gather intelligence in a matter of a few seconds while streaking across unfriendly skies. From 80,000 feet, it could survey 100,000 square miles of Earth’s surface per hour.
No SR-71 has ever been lost or damaged due to hostile action. The aircraft was extremely difficult for enemy radars to find.
On Aug, 26, 1981, in the midst of major exercises in North Korea that had people worried about a possible invasion, one of these Mach 3-capable spy planes was sent to track North Korea’s forces.
The United States wanted to get intelligence about missile sites in the very secretive country, and the Blackbird was often the aircraft of choice.
What made the Blackbird’s Aug. 26, 1981 mission unique though, was that this time, the regime of Kim Il-Sung took a shot at the speedy plane as it made a pass over the Demilitarized Zone, known as the DMZ. The mission profile often involved multiple passes.
Maury Rosenberg and Ed McKinn were making their third pass when they saw the rising plume of a missile. Rosenberg calmly turned his plane to the right, going away from North Korea, and he and McKinn watched the missile detonate.
Thanks to the SR-71’s high speed, the aircraft and the crew escaped the hit.
In response to the development of the the SR-71, the Soviet Union built the MiG-25 Foxbat to counter both the spy plane and the planned B-70 Valkyrie bomber. But even the Foxbat couldn’t stop the SR-71 from going where it wanted, when it wanted.
What did stop the SR-71? Budget cuts at the end of the Cold War.
Why did they retire the SR-71? In spite of the plane’s unparalleled service record, it was simply too expensive for the U.S. Air Force to continue to run after the end of the Cold War. Air Force officials were frank about this fact in 1989 hearings.