Work on stealth began in the mid 1970s with Project Harvey. It was a largely unclassified paper study. When Lockheed showed the potential for stealth, it was compartmentalized. The Have Blue prototype flew around 1978 in complete secrecy. By the summer of 1980, Armed Forces Journal magazine had learned of the program. At the government's request, they sat on the story.

During his reelection campaign, Jimmy Carter broke the story on stealth when criticized for being soft on defense. He didn't talk about Have Blue but he did talk about the stealth bomber. After that, Armed Forces Journal wrote a good article for their September 1980 issue.

The F-117A prototype first flew in 1981 in secrecy. Through most of the 1980s, there was discussion about stealth fighters but no one got it right. Tom Clancey used them in his book "Red Storm Rising". A model airplane company put out an "F-19 Stealth Fighter" model that was even featured in Congressional hearings. I remember seeing news footage of some Congressman holding up an F-19 model and demanding of a general everything he knew about the program. The general was able to say with complete accuracy that there was no such plane in existance.

During the 1980s, there were news stories about people who used to sit on hills outside Lockheed's Burbank plant roughly once a month. A C-5 would arrive with lights out and roll up to the loading dock. The speculation (almost certainly accurate) was that a Stealth fighter was being loaded on the plane. There was also an incident in the late 1980s where some engineer in the Skunk Works smuggled out a manual on the plane to impress his girlfriend.

The F-117A was unveiled to the public in a limited way around 1988. The extreme secrecy around the project made training more difficult and expensive than it needed to be.

Two weeks later, the B-2A prototype was rolled out in public. There was no way to conduct the B-2's flight tests in complete secrecy, so they didn't even try.

I agree that it's unlikely that a plane like the Aurora could exist and be flying regularly all these years in such secrecy. Unlikely, but not impossible. I'd like to believe it exists but, until some solid evidence is released, I'm somewhat skeptical.