U.S. Army helicopters providing support for U.S. ground troops fly into a staging area fifty miles northeast of Saigon, Vietnam, August 28, 1966. Helicopter fuel is stored in the large rubber tanks, foreground. (Photo by Henri Huet/AP Photo)

Colonel Roscoe Turner, the pilot of an American Boeing plane, showing his wife a model of the plane, at the airfield in Mildenhall. (Photo by R. Wesley/Fox Photos/Getty Images). 19th October 1934

(L-R) Senior Drum Major Betts of the Scotts Guard, Bugler Lee Kidd, Guardsman Adam Deer of the Coldstream Guards and Lance corporal Michael Strong of the Princess of Wales's Royal Regiment pose in their full ceremonial attire at Wellington Barracks on March 21, 2012 in London, England. The group make up part of the ceremonial military personnel who will play a key role during Her Majesty the Queens Diamond Jubilee celebrations between June 2–5. (Photo by Dan Kitwood/Getty Images)

Police investigators inspect the bodies of two men lying on a sidewalk, who police said were killed after a drug “Shabu” (Methamphetamine Chloride) buy-bust operation in Quezon city, Metro Manila Philippines, October 9, 2016. (Photo by Ezra Acayan/Reuters)

Jorge (2nd R), 31, who is among members of lesbian, gay, bisexual and transgender (LGBT) community and his brother Paulo, 28, (R) laugh at Arouche Square in downtown Sao Paulo, Brazil, November 20, 2016. (Photo by Nacho Doce/Reuters)

A picture taken on March 9, 2017, shows a boy playing with a cat next to a 1948 Buick parked outside the home of Mohammad Mohiedine Anis in the formerly rebel-held al-Shaar neighbourhood. (Photo by Joseph Eid/AFP Photo)

Women grieves near a bodies covered by tarp at the site of a landslide in Xinmo village in Maoxian County in southwestern China's Sichuan Province, Sunday, June 25, 2017. Crews searching through the rubble left by a landslide that buried a mountain village under tons of soil and rocks in southwestern China on Saturday found bodies, but more than 100 people remained missing. (Photo by Ng Han Guan/AP Photo)

Jing Li (L) and her husband Ke Xu wear Tibetan traditional costumes as they pose for their wedding photos in front of Tibetan prayer flags at the Nianqing Tanggula mountain pass in the Tibet Autonomous Region, China November 18, 2015. Jing, 22, and her husband Ke Xu, 23, both from Shiyan in northwestern Hubei province live in Tibet for three year. The couple married last month. (Photo by Damir Sagolj/Reuters)