At the risk of sounding even more bonkers, The Hunt for Zero Point claims that most UFOs are attributable to an exotic man-made propulsion technology first developed in the late 1940s and early 1950s.
While I don't particularly believe the book's claims, it's worth mentioning because Nick Cook wrote it. Cook was the former aviation editor for Jane's Defence Weekly, which was quite a prestigious position during his tenure.
Though I read the book over a decade ago, I'm still puzzled.
The book basically claims the U.S. launched an anti-gravity program based on technology it extracted from Nazi Germany in the later stages of WW2, and that the subsequent rash of UFO sightings in the U.S. were related. Supposedly the technology then started to make its way into the mainstream, and was abruptly quashed.
It also advanced a couple of theories suggesting the B-2 bomber is more than the public was led to believe—ranging from having hypersonic propulsion capability at altitude (unlikely), to a more benign theory of an electrified leading edge for both aerodynamic and stealth purposes. If I recall, the latter theory required the use of a highly toxic substance, and I could see that given the Air Force's troubled history with stealth coating toxicity.
The book also made claims of seemingly impossible transmutations being conducted by a fringe experimenter in his apartment, using high-voltage electricity. I'm sure there was more crazy stuff I failed to mention.
The reason the book continues to puzzle me is that, while it's easy to just say "Nick Cook went off the deep end", that isn't necessarily true. Despite the book being published in 2003, Cook remained as a consultant to Jane's from 2002 until 2008. In 2006 he uncovered a classified high-altitude UCAV program by digging through budget requests. Now he runs his own consultancy. Not exactly crazy.
My opinion is that while the majority of the book is probably not true, Cook may have been on to something. What exactly I'm unsure, other than that when you apply ridiculous amounts of electricity to objects in novel state or material configurations, you get interesting results. Whether that means there's some long-running government conspiracy to conceal such things is another question.
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