On April 1, 2001, a U.S. Navy EP-3E intelligence-gathering aircraft hit a Chinese J-8II fighter in mid-air, forcing the Navy intel plane to make an emergency landing on nearby Hainan Island – on a Chinese military installation. One Chinese pilot was killed, and the American crew was held captive and interrogated by the Chinese military.
Meanwhile, a trove of Top Secret American intelligence and intel-gathering equipment was sitting in Chinese hands.
A Chinese J-8 fighter.
The EP-3E Airborne Reconnaissance Integrated Electronic System, also known as ARIES, aircraft is used for signals intelligence gathering. Much of what these planes do is a close secret, and no one except its crew members really know how or what information they track, which makes what is now known as the "Hainan Island Incident" all the more damaging. When the crew of the EP-3E was forced to land – without permission – on the Chinese military base, it was basically handing China some of the U.S. military's most secret equipment.
At the end of the EP-3's six-hour mission, it was intercepted by Chinese jets near Hainan Island, itself an extremely important signals intelligence base for China. One of the Shenyang J-8 interceptors made three passes on the EP-3E, accidentally colliding with it on the third pass. The hit damaged the Navy plane and tore the Chinese fighter in two. After recovering from a steep, fast dive, the Navy crew tried to destroy all the sensitive equipment aboard. Sadly, they had not been trained on how to do that. Protocol for such an event would have been to put the plane into the sea and hope for rescue. Instead, the crew poured coffee into the electronic equipment and threw other sensitive documents out a hatch.
The EP-3E spy plane was flown out by a third party in an Antonov-124 cargo plane, the world's largest.
The crew conducted an emergency landing on Hainan Island's Lingshui Airfield, where they were taken into custody by the People's Liberation Army. They were interrogated and held for ten days as the United States negotiated their release. The Chinese demanded an apology for both the illegal landing and for their dead pilot, which the U.S. publicly announced. The plane required extra negotiation, as the Chinese wouldn't let the United States repair it and fly it out. The Navy had to hire a Russian company to fly it away.
When the Russians came to pick up the plane, they found it torn apart by the Chinese. It was returned to the Navy in pieces months later – and the Chinese presumably learned everything about America's most sensitive signals intelligence equipment. A later inquiry didn't fault the crew. In fact, the pilot received the Distinguished Flying Cross for saving the crew and the aircraft. Documents later released by Edward Snowden revealed the Navy didn't know how much sensitive material was aboard and inadequately prepared the crew for this eventuality.