Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)

A tunnel with electric switches are seen in Josip Broz Tito's underground secret bunker (ARK) in Konjic, October 16, 2014. In the early 1950s, Josip Broz Tito, the late leader of the former Yugoslavia, ordered the building of the secret bunker, located 900 feet (270 m) underground and near the Bosnian town of Konjic, to safeguard the country's ruling class in case of a nuclear attack. Construction at the complex, which had a cost equivalent price tag of $4.6 billion, continued until 1979, the year before Tito died. (Photo by Dado Ruvic/Reuters)

Colombian-Spanish actress Juana Acosta attends the Fotogramas Awards 2012 at Joy Eslava Club on March 12, 2012 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

Models pose backstage at the Celia Kritharioti Spring/Summer 2012 fashion show at One Mayfair on March 20, 2012 in London, England. (Photo by Ian Gavan/Getty Images For Celia Kritharioti)

Current England long jump champion and London 2012 hopeful J. J. Jegede attempts an exhibition jump over three Limited edition 2012 MINIs on September 28, 2011 in London, England. This world first is taking place to celebrate the launch of the MINI London 2012 Edition models, of which only 2,012 will be produced. (Photo by Julian Finney/Getty Images for BMW)

The 8th annual Miss International Queen beauty pageant was held in Pattaya in Thailand. The twenty-one contestants from fifteen countries were all born male, so the Miss International Queen 2012 pageant is not an average beauty pageant.

Photo: Panvilas Mongkol, a contestant from Thailand, waits for the start of the final night of Miss International Queen 2012 transgender/transsexual beauty pageant in Pattaya November 2, 2012. Some 21 contestants from 15 countries, all of them born male, compete in the week-long event for the crown of Miss International Queen 2012. (Photo by Damir Sagolj/Reuters)

Turkey's Merve Aydin cries after she came in last in her women's 800m round 1 heat at the London 2012 Olympic Games at the Olympic Stadium August 8, 2012. (Photo by Lucy Nicholson/Reuters)

“A prototype lunar lander was destroyed on August 9, 2012, at Kennedy Space Center during its first free flight”. – James Dean via Florida Today

Photo: Morpheus Ground Level Hot Fire. Photo Date: April 2nd 2012. Location: VTB Flight Complex; Photographer: Joe Bibby