For the Federal Aviation Administration, Jan. 29 was the beginning of one of the most challenging stretches it has faced in decades.

That night, an American Airlines regional jet collided with an Army helicopter near Ronald Reagan National Airport in Washington, resulting in 67 deaths. In a news conference the next day, President Trump pointed his finger at the F.A.A., even though the crash investigation was just beginning.

On Jan. 31, a medical jet crashed in a Philadelphia neighborhood shortly after takeoff, killing all six on board and one person on the ground. While it remains unclear whether the F.A.A.’s lack of oversight contributed to the episode, the timing has raised concerns.

Adding to the agency’s woes, on Feb. 1, an aviation alert system had an outage, its first in two years.

The 10-day period of crises was capped by another deadly crash on Feb. 6 involving Bering Air Flight 445 near Nome, Alaska, resulting in the deaths of 10 people.