Washington, DC —

A year and a half after a deadly midair collision at Ronald Reagan Washington National Airport killed 67 people, dozens of safety recommendations have been issued, and some changes were implemented, but problems with aircraft getting too close together persist.

Last Tuesday, planes continued to take off as Marine One lifted off from the Ellipse, just south of the White House, with President Donald Trump onboard. At least one American Airlines regional jet got within the protective bubble around the helicopter. Flights are typically halted from the nearby airport when the President is taking off.

“There was momentary loss of separation after which the aircraft continued to move away from one another,” the Federal Aviation Administration said, reaffirming the President was never in danger.

Transportation Secretary Sean Duffy said Tuesday the breakdown resulted from a telecommunications problem.