An injured fan is helped by a riot policeman during clashes between Red Star Belgrade and Partizan Belgrade fans in the stadium before the teams' Serbian Superliga soccer match in Belgrade, April 25, 2015. Serbian league leaders Partizan Belgrade held champions and bitter city foes Red Star to a 0-0 draw in a derby match marred by bad crowd trouble before kickoff on Saturday. The start was delayed for 45 minutes after home Red Star supporters pelted riot police with seats and flares, forcing officers to retreat from the north tier that houses the club's diehard fans. (Photo by Marko Djurica/Reuters)

The Boeing 747-8 Intercontinental airliner, the company's newest and largest passenger plane, takes off for its first test flight at Paine Field Airport March 20, 2011 in Everett, Washington. The new plane features quieter, more fuel efficient engines, more seating and a redesigned interior.

Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

For our latest mission, we put a Carnegie Hall orchestra in the middle of New York City and placed an empty podium in front of the musicians with a sign that read, “Conduct Us.” Random New Yorkers who accepted the challenge were given the opportunity to conduct this world-class orchestra. The orchestra responded to the conductors, altering their tempo and performance accordingly. This project was a collaboration with Carnegie Hall and Ensemble ACJW.

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)

Artist Princess Tarinan von Anhalt throws paint into the flow of air coming from the engine of Flexjet’s Learjet 40 XR engine to create a painting on a canvas at Signature Flight Support in West Palm Beach, Florida. The artist associated with the Jet Art Group used the help of Flexjet and their plane to spray paint on a canvas to create distinctive paintings to celebrate the 50th anniversary of Learjet. (Photo by Thomas Cordy/The Palm Beach Post)

Jesus Christ The Redeemer is seen during sunrise in Rio de Janeiro, Brazil August 2, 2016. Christ the Redeemer is an Art Deco statue of Jesus Christ in Rio de Janeiro, Brazil, created by Polish-French sculptor Paul Landowski and built by the Brazilian engineer Heitor da Silva Costa, in collaboration with the French engineer Albert Caquot. The face was created by the Romanian artist Gheorghe Leonida1. (Photo by Kai Pfaffenbach/Reuters)

Retired Malam Jabba engineer Akbar Ali skis down the piste at the ski resort in Malam Jabba, Pakistan February 7, 2017. Atop the piste of Malam Jabba in Pakistan's once dangerous Swat Valley skiers schuss downhill, a new Chinese-built chairlift ferries tourists to the peak, and a luxury hotel is under construction to replace one torched by the Taliban. (Photo by Caren Firouz/Reuters)