The crash on a clear August day in 2009 horrified New Yorkers and visitors alike. A sightseeing helicopter carrying five Italian tourists collided in mid-air over the Hudson River with a private Piper airplane carrying three members of a Pennsylvania family. There were no survivors.

Last year, the federal government quietly paid $18.675 million to Jaclyn Altman, whose husband and son were passengers on the airplane, to settle charges of negligence by air-traffic controllers.