Aviation safety and security

People wait to get through security at the Orlando International Airport following a security incident on Saturday, Feb. 2, 2019. Passengers on shuttles to gates at Florida's busiest airport had to be brought back for a second screening, bringing security checkpoints to a temporary standstill. A spokeswoman for Orlando International Airport told television station WKMG on Saturday that the passengers were returned in "an abundance of caution" after some passengers may have gotten through the checkpoints without being screened property. (Jonathan Hayward/The Canadian Press via AP)

FILE- In this Jan. 7, 2019, file photo a TSA agent, center, directs passengers through a security checkpoint at New York's John F. Kennedy International Airport. The strain of a 34-day partial government shutdown is weighing on the nation's air-travel system, both the federal workers who make it go and the airlines that depend on them. Unions that represent air traffic controllers, flight attendants and pilots are growing concerned about safety with the shutdown well into its fifth week. (AP Photo/Mark Lennihan, File)

FILE-In this March 15, 2015 file photo a Yemeni airport security official walks on the tarmac next to a plane from the Iranian private airline Mahan Air at the international airport in Sanaa, Yemen. Germany has banned Iran’s Mahan Air from landing in the country with immediate effect, citing security concerns and the airline’s involvement in Syria. (AP Photo/Hani Mohammed)

FILE - In this Dec. 10, 2008 file photo, a Eurostar train heading to London enters the Channel tunnel to England in Coquelles, northern France. France's government is kicking off a 50 million-euro (about $57 million) plan to prepare for the increasingly likely possibility that Britain will leave the European Union on March 29 without a plan. (AP Photo/Michel Spingler, File)

Security lines at Hartsfield-Jackson International Airport in Atlanta stretch more than an hour long amid the partial federal shutdown, causing some travelers to miss flights, Monday morning, Jan. 14, 2019. The long lines signaled staffing shortages at security checkpoints, as TSA officers have been working without pay since the federal shutdown began Dec. 22. (John Spink/Atlanta Journal-Constitution via AP)

A Transportation Security Administration officer works at the entrance to Concourse G at Miami International Airport, Friday, Jan. 11, 2019, in Miami. The airport is closing Terminal G this weekend as the federal government shutdown stretches toward a fourth week because security screeners have been calling in sick at twice the airport's normal rate. (AP Photo/Lynne Sladky)