Federal investigators looking for the cause of the January collision between a passenger jet and an Army helicopter near Washington, D.C., that killed 67 people recommended a ban on some helicopter flights Tuesday to improve safety. A military helicopter collided with the American Airlines jet as it was approaching Ronald Reagan National Airport over the Potomac River on Jan. 29. Among the victims were 28 members of the figure skating community. National Transportation Safety Board Chairwoman Jennifer Homendy said the board determined that the existing separation distance between planes and helicopters at Reagan National Airport is “insufficient and poses an intolerable risk to aviation safety.” MORE: https://www.wthr.com/article/news/nation-world/dc-plane-helicopter-collision-ntsb-preliminary-report/507-b2f461ab-22f8-4588-a2ad-c21795296437