The giant metal structure sits 330ft above the ground on the roof of a 22 storey office block in Dutch capital Amsterdam on September 6, 2016. Tourists sit in a playground-style chair as they propel themselves them over the edge of the building with only thin-air between them and the ground below. Engineers spent several years designing and building the breathtaking swing. By being fixed to the top of a building it reaches new heights – dwarfing other swings around Europe but trailing behind the 1,150ft high mechanical rides at the Stratosphere Hotel in Las Vegas, Nevada. (Photo by Huub Zeeman/SWNS.com)

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

Two F-15E Strike Eagles wait to receive fuel from a KC-135R Stratotanker during exercise Red Flag 15-1 on their way to Nellis Air Force Base, Nev., Jauary 23, 2015. The F-15s are assigned to the 4th Fighter Wing. U.S. (Photo by Airman 1st Class Aaron J. Jenne/Reuters)

Belarussian rhythmic gymnast Melitina Staniouta takes a selfie as she has her make-up done in Minsk, May 29, 2016. Photos show her training and competing, as well as trying on her official Olympic uniform and getting ready for a photo shoot. (Photo by Vasily Fedosenko/Reuters)

Sculptures entitled “The Rising Tide” by British sculptor Jason deCaires Taylor are seen beside the River Thames in front of the Houses of Parliament and the London Eye ferris wheel in London, September 3, 2015. The representations of four horses and riders are fully visible at low tide but become immersed underwater twice a day as the Thames rises to reach full tide. The installation will be on display throughout September as part of the annual Totally Thames festival. (Photo by Toby Melville/Reuters)

Revellers take part in an annual block party before Carnival in downtown Rio de Janeiro, Brazil, January 16, 2016. The Rio de Janeiro Carnival will be held from February 5 to February 9. (Photo by Pilar Olivares/Reuters)

Nepalese Mahuts with their elephant participate in elephant picnic as a part of the12th Chitawan Elephant Festival at Sauhara, Chitawan, some 154 kilometer from the capital of Kathmandu, Nepal, 28 December 2015. More than 80 elephant with their Mahuts joined the elephant picnic. The five-day festival began on 26 December to spread awareness about wildlife and promote tourism. (Photo by Hemanta Shrestha/EPA)

Male orangutan Percy is reflected in the Sekonyer River as he reaches over to try and touch a wooden klotok boat carrying crew and tourists, in Tanjung Puting National Park, in Kalimantan (Indonesian Borneo), Indonesia, September 4, 2013. Percy is a son, born and living in the wild, of a female orangutan named Princess, a freed former captive orangutan that anthropologist Dr Birute Galdikas rescued, rehabilitated and returned to the wild. (Photo by Barbara Walton/EPA)