Helicopter traffic should be permanently banned near Ronald Reagan Washington National Airport during certain periods to alleviate congestion and avoid a repeat of the deadly midair collision that occurred there in January,

The NTSB’s preliminary report on the Jan. 29 crash that killed 67 people said current helicopter routes allowed around the airport are an ‘intolerable risk to aviation safety.’

The National Transportation Safety Board on Tuesday called for immediate changes at Ronald Reagan Washington National Airport, saying the current helicopter routes around the busy airport "pose an intolerable risk to aviation safety.