Investigators issued their preliminary report Tuesday in the probe into the devastating crash between an American Airlines plane and a U.S. Army Black Hawk helicopter.

CHELAN, Wash. — The Johnson family is grieving the loss of their mother who was killed in a plane crash on March 4 in Kittitas County .

The NTSB determined the existing separation distance between planes and helicopters at Reagan National Airport is “insufficient" and poses an intolerable risk.