Bob Lazar - S4 flying disc case

In May 1989, he appeared in an interview with investigative reporter George Knapp on Las Vegas TV station KLAS, under the pseudonym "Dennis" and with his face hidden, to discuss his purported employment at "S-4", a subsidiary facility he claimed exists near the Nellis Air Force Base installation known as Area 51. He claims that the said facility was adjacent to Papoose Lake, which is located south of the main Area 51 facility at Groom Lake. He claimed the site consisted of concealed aircraft hangars built into a mountainside. Lazar said that his job was to help with the reverse engineering of one of nine flying saucers, which he alleged were extraterrestrial in origin. He claims one of the flying saucers, the one he coined the "Sport Model", was manufactured out of a metallic substance similar in appearance and touch to stainless steel. In a subsequent interview that November, Lazar appeared unmasked and under his own name, where he claimed that his job interview for work at the facility was contractor EG&G and his employer was the United States Navy; EG&G stated it had no records on him.

Lazar has claimed that the propulsion of the studied vehicle ran on an antimatter reactor and was fueled by the chemical element with atomic number 115 (E115), which at the time was provisionally named ununpentium and had not yet been artificially created. (It was first synthesized in 2003 and later named moscovium.) He further said that the propulsion system relied on a stable isotope of E115, which allegedly generates a gravity wave that allowed the vehicle to fly and to evade visual detection by bending light around it. No stable isotopes of moscovium have yet been synthesized; all have proven extremely radioactive, decaying in a few hundred milliseconds. Lazar also said the craft was dismantled, and the reactor he studied was topped by a sphere or semi-sphere which emitted a force field capable of repulsing human flesh. He explained that the craft was split into two main levels. The reactor was positioned at the center of the upper level, with an antenna extending to the top, surrounded by three "gravity amplifiers". These connected to "gravity emitters" on the lower level, which can rotate 180 degrees to output a "gravity beam or anti-gravity wave" and that the craft would then travel "belly first" into this distortion field.