Family members of some of the 67 people killed in January’s midair collision in Washington listened to the US Army and Federal Aviation Administration take fiery questions from lawmakers for the first time Thursday at a Senate subcommittee hearing on the preliminary findings of the accident.

The FAA announced today all helicopters flying around Reagan National Airport must turn on their geo-positioning transmitters, known as ADSB. The helicopter that collided with a passenger plane near Reagan in January did not have ADSB on,

Texas Sen. Ted Cruz said he learned that the Secret Service and U.S. Navy triggered a rash of collision alarms in planes around Reagan Airport on March 1 while testing anti-drone technology that used a similar frequency to the one used by planes' warning systems. Cruz said that happened despite a warning from the FAA against doing it.