Regulations changed after fatal TWA 514 crash at Dulles
At a National Transportation Safety Board hearing, Dulles principal controller Robert Logan said new landing rules were issued December 16 to prevent controllers from clearing landings before aircraft have cleared the Appalachian mountains west of the airport. The TWA 514 jet crashed into Mt Weather on December 1, killing all 92 aboard. The crew descended immediately after landing clearance, on a still unresolved dispute over the meaning of approach clearance between controllers and pilots.