Free Syrian Army fighters stand near an ambulance on the eastern edge of the northern Syrian town of al-Bab, Syria, February 27, 2017. (Photo by Khalil Ashawi/Reuters)

Migrants react after boarding the Migrant Offshore Aid Station (MOAS) ship MV Phoenix some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015. Some 118 migrants were rescued from a rubber dinghy off Libya on Monday morning. The Phoenix, manned by personnel from international non-governmental organisations Medecins san Frontiere (MSF) and MOAS, is the first privately funded vessel to operate in the Mediterranean. (Photo by Darrin Zammit Lupi/Reuters)

The X-47B prototype on Tuesday flew off an aircraft carrier and into the history books. Today's achievement, the first-ever catapult launch of an unmanned aircraft from the flight deck of a carrier, promises to open up a new chapter in the annals of naval aviation. Photo: An X-47B pilot-less drone combat aircraft is launched for the first time off an aircraft carrier, the USS George H. W. Bush, in the Atlantic Ocean off the coast of Virginia, May 14, 2013. The U.S. Navy made aviation history on Tuesday by catapulting an unmanned jet off an aircraft carrier for the first time, testing a long-range, stealthy, bat-winged plane that represents a jump forward in drone technology. (Photo by Jason Reed/Reuters)

Artist Pyotr Pavlensky sits on the wall enclosing the Serbsky State Scientific Center for Social and Forensic Psychiatry after he cut off a part of his earlobe during his protest action titled “Segregation” in Moscow October 19, 2014. Pavlensky protested against the usage of forensic psychiatry for politically motivated purposes. He cut off his earlobe to demonstrate how authorities could “cut off” an unwanted individual from society by using psychiatric and medical diagnosis to forcefully send a person to a penitentiary hospital, according to Pavlensky. (Photo by Maxim Zmeyev/Reuters)

Igor Perne (L), 53, an electronic engineer and a member of the International Virtual Aviation Organisation (IVAO), and fellow virtual pilot Franc Lavric gesture for the camera before taking off on a virtual flight in a flight simulator in Nova Vas, Slovenia November 13, 2014. In 2011, Perne, a lifelong flying enthusiast, bought parts of a written-off Cyprus Airways airliner and then spent two and a half years turning the entire nose of the scrapped aircraft into an elaborate flight simulator. (Photo by Srdjan Zivulovic/Reuters)

Princess Anne, Princess Royal waves off Zara Philips as she eaves Canongate Kirk on the afternoon of her wedding to Mike Tindall on July 30, 2011 in Edinburgh, Scotland. (Photo by Chris Jackson PT/Getty Images)

Sailors from the Indonesian Navy carry a victim of a boat sinking last week off the coast of Indonesia, on December 21, 2011 in Banyuwangi, East Java, Indonesia. (Photo by Ulet Ifansasti/Getty Images)

A kite surfer takes advantage of high winds and waves off Blackpool seafront on January 12, 2012 in Blackpool, England. Meteorologists are predicting calmer weather after high winds hit many parts of the North West today. (Photo by Christopher Furlong/Getty Images)