Hot air balloons take part in the 38th International Balloon Festival of Chateau-d'oex, Switzerland, 23 January 2016. For nine days balloonists from 15 countries take part in the ballooning event in the Swiss mountain resort famous for ideal flight conditions due to an exceptional microclimate. The festival takes place from 23 to 31 January. (Photo by Cyril Zingaro/EPA)

One of only three active female blimp pilots in the world, Kristen Arambula guides her passengers towards the Goodyear blimp “Spirit of America” in Carson, California August 5, 2015. Christened in 2002, the air ship is being retired after 8,000 flights and replaced with a newer more modern version named the “Spirit of Innovation” in September. (Photo by Mike Blake/Reuters)

Keira Knightly attends the UK Gala Premiere of “A Dangerous Method” at The Mayfair Hotel on January 31, 2012 in London, England. (Photo by Stuart Wilson/Getty Images)

Sports Illustrated Swimsuit model Alyssa Miller attends SI Swimsuit Launch Party Hosted by Crimson at Crimson on February 14, 2012 in New York City. (Photo by Michael Loccisano/Getty Images for Sports Illustrated)

Model Alba Carrillo attends “Glamour” beauty awards 2012 at Pacha Club on March 14, 2012 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

A supporter of the Houthi movement attends a rally marking the birth anniversary of Prophet Mohammed, in Sanaa, Yemen December 11, 2016. (Photo by Khaled Abdullah/Reuters)

Ukrainian Air Force officers attend a graduation ceremony at the National University of Defence of Ukraine in Kiev, April 24, 2015. (Photo by Gleb Garanich/Reuters)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)