An Army Sikorsky R-5 helicopter, undergoing record trials, demonstrates its lifting power by carrying 17 persons and pilot aloft as female onlookers wave in Bridgeport, Conn., January 10, 1946. During the tests records were claimed for altitude speed and both altitude and speed with payload. (Photo by Anthony Camerano/AP Photo)

Mercury and Maia, fueled and overhauled, are waiting in the Tay at Dundee, for favorable weather to start the flight to the Cape, a distance of 6,370 miles. The composite machine moored in the Tay River, at Dundee, on September 23, 1938. (Photo by AP Photo)

“Be prepared” is the motto of petite Doris Sherrell, vocalist and dancer with “Blackouts of 1942”. In the event of a bombing, the young lady had her social security number tattooed on one leg by artist Jack Julian, and address placed on the other limb for means of identification in Los Angeles, September 29, 1942. (Photo by AP Photo)

A man looks at kebabs cooking on the street side in Rawalpindi, Pakistan October 2, 2017. (Photo by Caren Firouz/Reuters)

Model Heidi Klum attends her 8th Annual Halloween Party at The Green Door on October 31, 2007 in Los Angeles, California. (Photo by Charley Gallay/Getty Images)

A “Free Syrian Army” fighter in the Bustan Pasha neighborhood of Aleppo, Syria, August 21, 2013. (Photo by James Lawler Duggan)

A helicopter pours water over a wildfire with the Space Shuttle Endeavour seen through heavy smoke in the background April 27, 2011 in Cape Canaveral, Florida. (Photo by Roberto Gonzalez/Getty Images)

Kaci Nuyen 8, holds a “Kiddizoom Twist” camera during a Hamleys Christmas toy photocall at Hamleys Toy store on June 28, 2011 in London, England. The famous toy store unveiled today their “must have” toys for Christmas 2011. (Photo by Dan Kitwood/Getty Images)