South Korea's Black Eagles aerobatics team performs an aerial display forming a Ying and Yang logo during the Singapore Airshow at Changi exhibition center in Singapore on February 16, 2016. (Photo by Roslan Rahman/AFP Photo)

Pilot Akmal Bin Abdul Kahar watches South Korea's Black Eagles aerobatics team perform a manoeuvre during an aerial display at the Singapore Airshow at Changi Exhibition Center February 18, 2016. (Photo by Edgar Su/Reuters)

Soldiers from Japan's Ground Self Defense Force come ashore in amphibious assault vehicle as they train alongside U.S. Marines during the bilateral annual Iron Fist military training exercise in Camp Pendleton, California February 26, 2016. (Photo by Mike Blake/Reuters)

(L-R) Barbara Palvin, Bella Hadid and Izabel Goulart appear on stage at the amfAR's 23rd Cinema Against AIDS Gala at Hotel du Cap-Eden-Roc on May 19, 2016 in Cap d'Antibes, France. (Photo by Andreas Rentz/Getty Images)

Pakistani youths cool off in a stream during hot weather on the outskirts of Islamabad on April 29, 2016. Pakistan's Meteorological Department has forecast hot and dry weather in most parts of the country with the highest temperatures recorded at 41 celsius in the southern Sindh province. (Photo by Aamir Qureshi/AFP Photo)

Ultra-Orthodox Jews dance next to a bonfire during celebrations for the Jewish holiday of Lag Ba-Omer in Jerusalem's Mea Shearim neighbourhood May 25, 2016. This day marks the hillula (celebration, interpreted by some as anniversary of death) of Rabbi Shimon bar Yochai, a Mishnaic sage and leading disciple of Rabbi Akiva in the 2nd century, and the day on which he revealed the deepest secrets of kabbalah in the form of the Zohar (Book of Splendor), a landmark text of Jewish mysticism. (Photo by Ronen Zvulun/Reuters)

A technician holds a recently 3D printed replica of Darth Vader's melted helmet from “Star Wars: The Force Awakens”, in the Propshop headquarters at Pinewood Studios near London, Britain May 25, 2016. Propshop headquarters at Pinewood Studios is making limited edition replicas of Star Wars props. (Photo by Peter Nicholls/Reuters)

Aerobatic pilot Sean D. Tucker flies in the two-seat Oracle Extra airplane over downtown Chicago skyline, Wednesday, June 8, 2016. Tucker will perform before the start of of the America's Cup World Series racing on Saturday and Sunday. (Photo by Kiichiro Sato/AP Photo)