Testifying for the first time in front of the Senate Subcommittee on Aviation, acting Federal Aviation Administrator Chris Rocheleau admitted that "something was missed."

Helicopters should be barred from a four-mile stretch over the Potomac River when flights are landing on Reagan National Airport’s Runway 33, National Transportation Safety Board Chair Jennifer Homendy said as the NTSB unveiled “urgent safety recommendations” after the deadly mid-air collision in January.

The agency said it’s taking steps to lessen the risk of collisions, but lawmakers say too many gaps remain — and place part of the blame on the military.