Officials want to permanently keep helicopters away from commercial jets taking off and landing at a busy Washington, D.C., airport after the deadliest U.S. aviation accident in more than two decades.

The FAA has reopened two runways at Reagan Airport following the Jan. 29 plane crash between an American Airlines flight and a Black Hawk helicopter.

Washington, D.C., is a unique city for many reasons, one being its prominence as a government and military hub. The growing, conflicting demands on close-in ...