The transportation secretary, Sean Duffy, said the Federal Aviation Administration had used a backup system while it addressed the problem.

Residents of Northeast Philadelphia looked on in disbelief after the crash on Friday night that also injured at least 19 people on the ground.

Commercial planes have technology that helps prevent crashes — but it has limitations, which was highlighted by the accident in Washington.

The city had tried for years to host the U.S. Figure Skating Championships, and to get a direct flight to the northeast.

The Learjet, carrying a pediatric patient and five others, crashed on Friday, killing all on board. On the ground, one person was killed and at least 19 others were injured, officials said.

Sixty-seven people were killed after an American Airlines jet and a U.S. Army helicopter collided and crashed into the Potomac River.

The last survivor of the American team that competed in Hitler’s 1936 Games in Berlin, she went on to become a wartime pilot and an aeronautics instructor.

The country’s leader, Gustavo Petro, backed down after a clash with President Trump, which started when Mr. Petro turned back U.S. military planes carrying deportees.

Airlines have been increasingly outsourcing repair and upkeep work to other countries, but experts and consumer groups disagree about its impact on safety.

The Transportation Department said in a lawsuit that two of the airline’s routes were consistently delayed in violation of federal rules.

Russia’s president is said to have blamed birds or a Ukrainian drone for a Dec. 25 crash of an Azerbaijani plane. Azerbaijan says Russian air defenses were at fault.

The White House scrambled to get a message to President Vladimir V. Putin of Russia last year after U.S. intelligence agencies said a Russian military unit was preparing to send explosive packages on cargo planes.

The industry is enjoying a strong demand for tickets and rising profits, but it remains vulnerable to unexpected problems like a recession or a surge in inflation.

The storm caused thousands of flights and dozens of train trips to be delayed or canceled. At Ronald Reagan National Airport in Washington, all runways were closed Monday evening.

The Transportation Department’s first ever penalty for chronic delays takes aim at four routes that consistently arrived late for five consecutive months.

A restaurant owner described witnessing the Jeju Air plane crash and recording videos as it happened. “Every time I closed my eyes, I kept seeing afterimages of the blast.”

The time between when the pilot reported a bird strike and when it crashed could be key to unraveling one of the world’s worst aviation disasters in years.

Aviation safety analysts said they expect officials investigating the crash, which killed 179 people, to look into the location and composition of a structure housing an antenna.

A Jeju Air passenger jet carrying 181 people from Bangkok sped off the runway and burst into flames. Two crew were rescued in what was the country’s worst air disaster in decades.