Air Force One casts its shadow over homes as it comes in to land in Allentown, Pennsylania with U.S. President George W. Bush aboard in this October 1, 2004 file photo. (Photo by Jason Reed/Reuters)

A storm is seen in Sarasota, Florida, June 24, 2018. (Courtesy of Val Vasilescu/Facebook.com/Kingofsunsets via Reuters)

The Sculpture Bank (2017) by Chinese artist Mu Boyan is exhibited along the Bondi to Tamarama Coastal walk as part of the Sculpture by the Sea exhibition in Sydney, Australia, October 18, 2018. (Photo by Charlotte Curd/The Guardian)

A model walks down the runway at the 13th China International Young Fashion Designers Contest during China Fashion Week on March 25, 2005 in Beijing, China. (Photo by China Photos/Getty Images)

A tow car for the children's “Grand Prix” races which take place in a parking lot in Livonia, Michigan a suburb of Detroit, circa 1955. (Photo by Three Lions/Getty Images)

A motorcycle fitted out to look like a giant telephone in an effort by the GPO to bring home to the public the importance of the phone. The dial on the wheel bears the slogan, “The World at Your Finger Tips”. (Photo by Topical Press Agency/Getty Images). 20th June 1932

Guests on the terrace of Shepheard's Hotel, Cairo, circa 1940. (Photo by Hulton Archive/Getty Images)

“The Boeing X-45 unmanned combat air vehicle is a concept demonstrator for a next generation of completely autonomous military aircraft, developed by Boeing's Phantom Works. Manufactured by Boeing Integrated Defense Systems, the X-45 was a part of DARPA's J-UCAS project”. – Wikipedia

Photo: Two X-45A Unmanned Combat Air Vehicles (UCAV) are shown to members of the news media July 11, 2002 at Edwards Air Force Base, California. The X-45A, developed by The Defense Advanced Research Projects Agency and the Boeing Company, is the first unmanned system designed from inception for combat missions. (Photo by David McNew/Getty Images)