http://www.nytimes.com/2008/04/01/scien ... =permalink
Of particular interest
In this research, Mr. Paglen became fascinated by the patches and started collecting them and displaying them at talks and shows. He said a breakthrough occurred around 2004, when he visited Peter Merlin, an “aerospace archaeologist” who works in the Mojave Desert not far from a sprawling military base. Mr. Merlin argued that the lightning bolts, stars and other symbols could be substantive clues about unit numbers and operating locations, as well as the purpose of hidden programs.
“These symbols,” Mr. Paglen wrote, “were a language. If you could begin to learn its grammar, you could get a glimpse into the secret world itself.”
His book explores this idea and seeks to decode the symbols. Many patches show the Greek letter sigma, which Mr. Paglen identifies as a technical term for how well an object reflects radar waves, a crucial parameter in developing stealthy jets.
A patch from a Groom Lake unit shows the letter sigma with the “buster” slash running through it, as in the movie “Ghost Busters.” “Huge Deposit — No Return” reads its caption. Huge Deposit, Mr. Paglen writes, “indicates the bomb load deposited by the bomber on its target, while ‘No Return’ refers to the absence of a radar return, meaning the aircraft was undetectable to radar.”