Since the start of the Snowden-revelations in 2013, many people got the impression that the US National Security Agency (NSA) mainly intercepts the communications of ordinary citizens. In reality, the NSA is part of the Department of Defense and as such, a large part of its job is to collect data for tactical military purposes.
A good example of the latter task comes from an internal NSA damage assessment report about the 2001 Hainan Island incident, in which an EP-3E electronic surveillance aircraft collided with a Chinese fighter jet and had to make an emergency landing on the Chinese island of Hainan.
The report was among the Snowden-documents and published by The Intercept on April 10. As will be shown here, it provides many details about both the interception and the encryption equipment aboard the EP-3E aircraft.
http://electrospaces.blogspot.com/2017/05/the-equipment-aboard-ep-3e-electronic.html