Project Skyvault was a leaked covert black project developed by Hughes Aircraft beginning in the 1950s. One key feature said to be attributed to Skyvault craft is their distinct diamond shape... The first batch of ufo disclosure releases featured two high quality military videos of a diamond shaped craft in operation...
To learn more about Project Skyvault, read Dr. Paul LaViolette's book, "Secrets Of Antigravity Propulsion" (available for download for premium members on my website in the ATR Digital Library).
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