French Navy Rafale fighter jets are seen from the bridge of the aircraft carrier Charles de Gaulle at Changi Naval Base in Singapore, May 28, 2019. REUTERS/Feline Lim

Russian jet fighters fly over a bridge connecting the Russian mainland with the Crimean Peninsula with a cargo ship beneath it after three Ukrainian navy vessels were stopped by Russia from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov TPX IMAGES OF THE DAY

Russian jet fighters fly over vessels after the channel beneath a bridge connecting the Russian mainland with the Crimean Peninsula was blocked to stop three Ukrainian navy ships from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov

Russian jet fighters fly over vessels after the channel beneath a bridge connecting the Russian mainland with the Crimean Peninsula was blocked to stop three Ukrainian navy ships from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov

Russian jet fighters fly over a bridge connecting the Russian mainland with the Crimean Peninsula after three Ukrainian navy vessels were stopped by Russia from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov

Russian jet fighters fly over a bridge connecting the Russian mainland with the Crimean Peninsula with a cargo ship beneath it after three Ukrainian navy vessels were stopped by Russia from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov

Russian jet fighters fly over a bridge connecting the Russian mainland with the Crimean Peninsula after three Ukrainian navy vessels were stopped by Russia from entering the Sea of Azov via the Kerch Strait in the Black Sea, Crimea November 25, 2018. REUTERS/Pavel Rebrov

Pasengers walk on a jet bridge to board a plane at Nice International airport in Nice, France, September 19, 2018. REUTERS/Eric Gaillard

People walk on a bridge on a summer day near the Jet d'Eau (water fountain) in Geneva, Switzerland, August 16, 2018. REUTERS/Denis Balibouse

People walk on a bridge on a summer day near the Jet d'Eau (water fountain) in Geneva, Switzerland, August 16, 2018. REUTERS/Denis Balibouse

90th Academy Awards - Oscars Show - Hollywood, California, U.S., 04/03/2018 - Best Costume Design winner Mark Bridges rides a jet ski with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson TPX IMAGES OF THE DAY

90th Academy Awards - Oscars Show - Hollywood, California, U.S., 04/03/2018 - Best Costume Design winner Mark Bridges rides a jet ski onto the stage as Oscars host Jimmy Kimmel gives actress Helen Mirren a kiss after Bridges won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show – Hollywood - Best Costume Design winner Mark Bridges rides a jet ski onto the stage as Oscars host Jimmy Kimmel gives actress Helen Mirren on the back a kiss after Bridges won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show - Hollywood, California, U.S., 04/03/2018 - Best Costume Design winner Mark Bridges rides a jet ski onto the stage with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show – Hollywood - Best Costume Design winner Mark Bridges rides a jet ski with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show - Hollywood, California, U.S., 04/03/2018 - Best Costume Design winner Mark Bridges rides a jet ski with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show – Hollywood - Best Costume Design winner Mark Bridges rides a jet ski with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

90th Academy Awards - Oscars Show - Hollywood, California, U.S., 04/03/2018 - Best Costume Design winner Mark Bridges rides a jet ski with actress Helen Mirren on the back after he won it for the shortest Oscar acceptance speech of 2018. REUTERS/Lucas Jackson

People ride jet skis on the East River in front of the Brooklyn Bridge on a warm day in New York City, U.S., August 13, 2017. REUTERS/Joe Penney

Trucks move across the bridge linking North Korea with the Chinese border city of Dandong in this March 3, 2016 file photo. China on Tuesday, April 5, 2016, banned imports of gold and rare earths from North Korea as well as exports to the country of jet fuel and other oil products used to make rocket fuel, a move in line with new United Nations sanctions on Pyongyang. REUTERS/Megha Rajagopalan

Pope Francis descends the stairs of the papal plane after arriving in the United States at Joint Base Andrews outside Washington September 22, 2015. REUTERS/Tony Gentile

Pope Francis descends the air stairs from his aircraft to be welcomed by U.S. President Barack Obama (not pictured) upon his arrival at Joint Base Andrews outside Washington September 22, 2015. REUTERS/Kevin Lamarque

Pope Francis arrives for the first time in the United States at Joint Base Andrews, Maryland September 22, 2015. REUTERS/Kevin Lamarque

An Air Force personnel keeps watch as a crew member removes the passenger stairs from Air Force One after U.S. President Barack Obama's arrival at Joint Base Andrews in Washington September 14, 2015. Obama traveled to Des Moines, Iowa to hold a town hall to discuss college access and affordability. REUTERS/Carlos Barria

U.S. President Barack Obama salutes as he disembarks from Air Force One at Joint Base Andrews, Maryland, August 25, 2015. President Barack Obama, fresh from vacation and nine rounds of golf in MarthaÕs Vineyard, launched into a busy two weeks promoting renewable energy and his nuclear deal with Iran. REUTERS/Carlos Barria

U.S. President Barack Obama arrives aboard Air Force One at Joint Base Andrews, Maryland, August 25, 2015. President Barack Obama, fresh from vacation and nine rounds of golf in Martha's Vineyard, launched into a busy two weeks promoting renewable energy and his nuclear deal with Iran. REUTERS/Carlos Barria TPX IMAGES OF THE DAY

U.S. President Barack Obama waves as he boards Air Force One on the way back to Washington at the McCarran International Airport in Las Vegas, Nevada August 25, 2015. REUTERS/Carlos Barria

U.S. Secretary of State John Kerry walks up the stairs as he boards his aircraft from Andrews Air Force Base for a flight to Havana, Cuba, August 14, 2015. Kerry declared a new era in relations as he celebrated restored diplomatic ties in Havana on Friday, but he also urged political change in Cuba, telling Cubans they should be free to choose their own leaders. REUTERS/Pablo Martinez Monsivais/Pool

U.S. President Barack Obama arrives aboard Air Force One at Jomo Kenyatta International Airport in Nairobi July 24, 2015. U.S. President Barack Obama flew into Kenya late on Friday for his first presidential visit to his father's homeland, aiming to boost trade and security ties in east Africa. REUTERS/Thomas Mukoya

U.S. President Barack Obama arrives to board Air Force One for travel to Kenya and Ethiopia from Joint Base Andrews, Maryland July 23, 2015. Obama will land in Kenya on Friday with a mission to strengthen U.S. security and economic ties, but his personal connection to his father's birthplace will dominate a trip that Kenyans view as a native son returning home. REUTERS/Jonathan Ernst

U.S. President Barack Obama boards Air Force One for travel to Kenya and Ethiopia from Joint Base Andrews, Maryland July 23, 2015. Obama will land in Kenya on Friday with a mission to strengthen U.S. security and economic ties, but his personal connection to his father's birthplace will dominate a trip that Kenyans view as a native son returning home. REUTERS/Jonathan Ernst

U.S. President Barack Obama waves as he boards Air Force One for travel to Kenya and Ethiopia from Joint Base Andrews, Maryland July 23, 2015. Obama will land in Kenya on Friday with a mission to strengthen U.S. security and economic ties, but his personal connection to his father's birthplace will dominate a trip that Kenyans view as a native son returning home. REUTERS/Jonathan Ernst TPX IMAGES OF THE DAY

U.S. President Barack Obama boards Air Force One for travel to Kenya and Ethiopia from Joint Base Andrews, Maryland July 23, 2015. Obama will land in Kenya on Friday with a mission to strengthen U.S. security and economic ties, but his personal connection to his father's birthplace will dominate a trip that Kenyans view as a native son returning home. REUTERS/Jonathan Ernst

A passenger jet makes its final approach over the Memorial Bridge in Washington, United States June 1, 2015. Completed in January of 1932 to connect Washington and Arlington National Cemetery, the bascule center portion of the bridge, which last opened in 1961, is rusting away and in need of serious repairs. Last month, U.S. President Barack Obama who said he was in discussions with congressional leaders on an infrastructure funding bill asked for a six-year, $478 billion transportation bill but lawmakers have not reached agreement on how to fund a long-term bill. Photo taken June 1. REUTERS/Gary Cameron

A passenger jet makes its final approach over the Memorial Bridge in Washington, United States June 1, 2015. Completed in January of 1932 to connect Washington and Arlington National Cemetery, the bascule center portion of the bridge, which last opened in 1961, is rusting away and in need of serious repairs. Last month, U.S. President Barack Obama who said he was in discussions with congressional leaders on an infrastructure funding bill asked for a six-year, $478 billion transportation bill but lawmakers have not reached agreement on how to fund a long-term bill. Photo taken June 1. REUTERS/Gary Cameron

The roof of the Sydney Opera House is pictured as a JetStar Airlines Airbus A320 plane flies near delegates from the inaugural China Australia Millennial Project (CAMP) summit as they stand atop the Sydney Harbour Bridge in Australia June 1, 2015. The climb was the opening event of the five-day summit which is being promoted as a way for "industry and government leaders from both countries to create a more innovative, collaborative Australia-China relationship". REUTERS/David Gray TPX IMAGES OF THE DAY

Passengers board a Ukrainian airplane at Bassel al-Assad international airport in Latakia, May 24, 2015. Syria welcomed its first commercial flight from Europe in three years as an Autolux flight from the Ukrainian capital Kiev arrived in the government-held coastal city of Latakia on Sunday. Only 10 passengers arrived in Syria on the flight with return tickets costing around $600 per person. Picture taken May 24, 2015. REUTERS/Omar Sanadiki TPX IMAGES OF THE DAY

Yemenis, who were stranded in Egypt, pray as they disembark from their plane after returning home, at Sanaa international aiport May 20, 2015. Some 200 Yemenis who have been stuck in Egypt and unable to return home arrived in the capital Sanaa on Wednesday in the first such flight from Egypt, though many more are expected in the coming days and weeks, officials say. REUTERS/Khaled Abdullah

A man holds an umbrella as he stands on the deck of a tourist boat that passes under jets of water that shoot from the Moonlight Rainbow Fountain running along Banpo Bridge in Seoul, May 10, 2015. REUTERS/Thomas Peter

Jet fighters from the Su-30 SM "Sokoly Rossii" (Falcons of Russia) aerobatic team fly during rehearsals for a show above the Yenisei River in Krasnoyarsk, Siberia, October 24, 2014. The show is conducted as part of a recruitment drive for Russia's military divisions, targeting the youth towards contractual military service, according to organizers. REUTERS/Ilya Naymushin (RUSSIA - Tags: MILITARY SOCIETY)

An Australian national flag and a New South Wales state flag (top) fly at half-mast atop the Sydney Harbour Bridge on July 19, 2014, as a sign of respect for those killed in the Malaysia Airlines passenger jetliner MH17 that crashed over eastern Ukraine. At bottom, a ferry passes the Sydney Opera House. Australian Prime Minister Tony Abbott blamed Russia on Friday for the shooting down of MH17, killing all 298 people on board, including 28 Australians. Abbott appeared to go further than other Western leaders in apportioning blame over the crash, demanding that Moscow answer questions about the "Russian-backed rebels" that he said were behind the disaster. REUTERS/David Gray (AUSTRALIA - Tags: TRANSPORT DISASTER)

A Swiss flag flies over the Jet d'Eau (Water Fountain) on the Mont-Blanc bridge over Lake Leman in Geneva March 21, 2014. REUTERS/Denis Balibouse (SWITZERLAND - Tags: SOCIETY TRAVEL)

U.S. Navy guided-missile destroyer USS Truxtun passes under the Bosphorus bridge in Istanbul, on its way to the Black Sea March 7, 2014. A U.S. warship passed through Turkey's Bosphorus straits on Friday on its way to the Black Sea, in what the U.S. military has described as a "routine" deployment scheduled well before the crisis in Ukraine. Washington announced the deployment on Thursday, a day after the Pentagon unveiled plans to put more U.S. fighter jets on a NATO air patrol mission in the Baltics in a bid to reassure allies alarmed by Russia's effective seizure of Ukraine's Crimea peninsula, which juts into the north of the Black Sea. REUTERS/Murad Sezer (TURKEY - Tags: POLITICS MILITARY MARITIME)

Charleston Harbor is seen at dawn from the top of the Arthur Ravenel Jr. Bridge that leads into Charleston, South Carolina December 18, 2013. Finished in 2005, the bridge has quickly become an iconic image for the historical city. Unionized machinists in Washington state last month rejected a labor contract that would have guaranteed Boeing's new jet program, known as the 777X, be built there. Boeing has operations in about 40 states, but among its most likely options are North Charleston in South Carolina and Long Beach in California. Picture taken December 18, 2013. REUTERS/Randall Hill (UNITED STATES - Tags: BUSINESS EMPLOYMENT TRAVEL CITYSPACE TRANSPORT)

Katie Long, 21, and Nike Pappas, 19, both of Charleston, stretch during their daily run across the Arthur Ravenel Jr. Bridge that leads into Charleston, South Carolina on December 18, 2013. Finished in 2005, the bridge has quickly become an iconic image for the historical city. Unionized machinists in Washington state last month rejected a labor contract that would have guaranteed Boeing's new jet program, known as the 777X, be built there. Boeing has operations in about 40 states, but among its most likely options are North Charleston in South Carolina and Long Beach in California. Picture taken December 18, 2013. REUTERS/Randall Hill (UNITED STATES - Tags: BUSINESS EMPLOYMENT TRAVEL CITYSPACE TRANSPORT)

The moon sets over the Arthur Ravenel Jr. Bridge that leads into Charleston, South Carolina early December 18, 2013. Finished in 2005, the bridge has quickly become an iconic image for the historical city. Unionized machinists in Washington state last month rejected a labor contract that would have guaranteed Boeing's new jet program, known as the 777X, be built there. Boeing has operations in about 40 states, but among its most likely options are North Charleston in South Carolina and Long Beach in California. Picture taken December 18, 2013. REUTERS/Randall Hill (UNITED STATES - Tags: BUSINESS EMPLOYMENT TRAVEL CITYSPACE TRANSPORT)

An Air France plane, which will carry French national Florence Cassez to France following her release, is parked next to a jet bridge at the International airport in Mexico City January 23, 2013. Mexico's top court on Wednesday freed Cassez, who was convicted of kidnapping, ruling that her trial was tainted and ending a seven-year imprisonment that strained ties with France. Cassez was sentenced to 60 years in prison after she was arrested in 2005 at a ranch near Mexico City with her former boyfriend, who led a kidnapping gang called the Zodiacs. REUTERS/Henry Romero (MEXICO - Tags: POLITICS CRIME LAW TRANSPORT)

A plane takes off near the new terminal dedicated for A380 aircraft at the concourse in Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match Story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

Divisional Senior Vice President of Emirates Airlines, Adnan Kazim, speaks as the new terminal dedicated for A380 aircraft is seen in the background at the concourse in Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: BUSINESS TRANSPORT)

A plane passes in between the Emirates Airlines terminal (L) and the new terminal dedicated for A380 aircraft at the concourse in Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

A plane is seen beside the new terminal dedicated for A380 aircraft at the concourse in Dubai International Airport January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

Screens display flight departure information at the Emirates terminal at Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: BUSINESS TRANSPORT)

A ground staff member arranges luggage trolleys at the Emirates terminal at Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

Travellers are seen at the Emirates terminal at Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: BUSINESS TRANSPORT)

A plane passes next to the Emirates Airlines terminal at the concourse in Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

Divisional Senior Vice President of Emirates Airlines, Adnan Kazim, gestures towards the new terminal dedicated for A380 aircraft at the concourse in Dubai International Airport, January 7, 2013. With the opening of a huge new airport terminal in Dubai this week, the wealthy emirate's economic future became more closely intertwined with the world's biggest passenger jet. Emirates, Dubai's state-owned flagship airline, began flying from the world's first airport terminal that was purpose-built to handle Airbus A380 superjumbos. The 528,000 square metre terminal cost over $3 billion to build and has 20 gates with double-decker bridges to move passengers on and off the twin-deck A380s. Picture taken January 7, 2013. To match story EMIRATES-AIRPORT/SUPERJUMBOS REUTERS/Jumana El Heloueh (UNITED ARAB EMIRATES - Tags: TRANSPORT BUSINESS)

A staircase for U.S. Republican presidential nominee and former Massachusetts Governor Mitt Romney to be used to step off his campaign plane sits on the tarmac prior to his arrival at the site of a campaign rally in Dubuque, Iowa, November 3, 2012. REUTERS/Jim Young (UNITED STATES - Tags: POLITICS ELECTIONS USA PRESIDENTIAL ELECTION)

Retired space shuttle Endeavour is carried on the back of a NASA jet as it passes the Golden Gate Bridge in San Francisco, California September 21, 2012. Endeavour will be moved to its permanent home at the California Science Center mid-October. REUTERS/Robert Galbraith (UNITED STATES - Tags: SCIENCE TECHNOLOGY TRANSPORT)

Retired space shuttle Endeavour is carried on the back of a NASA jet as it approaches the Golden Gate Bridge in San Francisco, California September 21, 2012. Endeavour will be moved to its permanent home at the California Science Center mid-October. REUTERS/Robert Galbraith (UNITED STATES - Tags: SCIENCE TECHNOLOGY TRANSPORT)

Retired space shuttle Endeavour is carried on the back of a NASA jet as it approaches the Golden Gate Bridge in San Francisco, California September 21, 2012. Endeavour will be moved to its permanent home at the California Science Center mid-October. REUTERS/Robert Galbraith (UNITED STATES - Tags: SCIENCE TECHNOLOGY TRANSPORT TPX IMAGES OF THE DAY)