Cockpit conversations a few minutes before the crash indicate that the crew may not have had accurate altitude readings, with the helicopter’s pilot calling out that they were at 300 feet (91 ...

Duffy, after the crash, restricted helicopter traffic around the airport and over the Potomac River until the end of March. “We are going to continue with our restrictions,” he said Tuesday.

The NTSB earlier in the day announced a number of recommendations to address a "serious safety risk" in the wake of the deadly crash. The collision between a military helicopter and an American ...