Midget pilots developed using human experiments by Josepf Mengele. Actually aliens seem more plausible.
Huffington

Huffington
ROSWELL, N.M. — A new book says the Roswell "incident" was no UFO but rather a Russian craft with "grotesque, child-size aviators" developed in human experiments by Nazi doctor and war criminal Josef Mengele.
That latest theory is floated by investigative journalist Annie Jacobsen in a work entitled "Area 51: An Uncensored History of America's Top Secret Military Base."
It's about the secretive Nevada base called Area 51. One chapter gives the new Roswell theory, citing an anonymous source who says Joseph Stalin recruited Mengele and sent the craft into U.S. airspace in 1947 to spark public hysteria.
Julie Schuster with the International UFO Museum and Research Center in Roswell says she hasn't read the book. But she says any new theories fuel public interest, and that's terrific.