Pilots have long worried about the congested and complex airspace around Reagan National near the heart of the capital, where flights must maneuver around military aircraft and restricted areas. It was no secret there had been previous close calls, but the numbers found by the NTSB were alarming.

Two Republican senators are set to question a top U.S. Army official and examine the preliminary findings of the National Transportation Safety Board’s (NTSB) report into the deadly place crash in January near Reagan Washington National Airport.