Airport operation

A demonstrator holds a flare as French railway workers gather at the Gare de l'Est train station before marching in the streets of Paris, France, Thursday, March 22, 2018. Employees of the national railway company SNCF reject a government plan aimed at adapting the company ahead of opening the service to competition. (AP Photo/Christophe Ena)

Cars in snowy conditions on the A192 road near Blyth, north east England, Thursday March 1, 2018. Persistent snow and freezing conditions are causing delays in many parts of Britain, with roads and train service hit particularly hard. Emergency officials said many drivers had to be rescued from stranded vehicles. (Owen Humphreys/PA via AP)

FILE -- In this Nov. 1, 2015 file photo provided by Russian Emergency Situations Ministry, Egyptian military approach a plane's tail at the wreckage of a passenger jet bound for St. Petersburg in Russia that crashed in Hassana, Egypt. Cairo airport officials said Tuesday Feb. 20, 2018, that the planned resumption of Russian flights to Egypt, has been postponed until April, citing delays in reopening offices of the two countries' national airlines. (Maxim Grigoriev/Russian Ministry for Emergency Situations via AP, File)

Planes on the apron at London City Airport which has been closed after the discovery of an unexploded Second World War bomb was found in the nearby River Thames, Monday Feb. 12, 2018. (Dominic Lipinski/PA via AP)

FILE - In this Jan. 8, 2018, file photo, unclaimed baggage sits at New York's John F. Kennedy Airport after a water pipe burst following several days of weather-related delays in the wake of a powerful winter storm. Over a week after winter weather woes snowballed into a long weekend of dysfunction at the airport, some passengers are still waiting for their baggage. The still-missing luggage is a fraction of the thousands of unclaimed bags that accumulated during the chaos. (AP Photo/Richard Drew, File)

Turkey's President Recep Tayyip Erdogan, right, shakes hands with Qatar's Sheikh Tamim bin Hamad Al Thani, prior to their meeting in Ankara, Turkey, Monday, Jan. 15, 2018. Al Thani's visit comes as the United Arab Emirates on Monday claimed that Qatari fighter jets intercepted two of its commercial airliners in international airspace on the way to Bahrain, allegations promptly denied by a Doha official. (Yasin Bulbul /Pool Photo via AP)

FILE--In this Oct. 24, 2017, file photo, the air traffic control tower is in sight as a plane takes off from San Francisco International Airport in San Francisco. An Aeromexico passenger jet was ordered to abort a landing at San Francisco International Airport Tuesday, Jan. 9, 2018, as it descended toward a runway occupied by another commercial jet, the third close call at the busy airport in six months. (AP Photo/Jeff Chiu, file)

Icicles form on the tritons in the Forsyth Park Fountain Tuesday morning, Jan. 2, 2018, in Savannah, Ga. Savannah is shivering through a rare bout with icy weather, with the National Weather Service predicting that up to 2 inches of snow and sleet could fall Wednesday on the typically balmy coastal city. (Steve Bisson/Savannah Morning News via AP)