Family members of the victims of the plane crash in Washington, D.C., visited the crash site on Sunday morning. Dozens of the victims' loved ones could be seen gathered by the Potomac River to commemorate the 67 people killed in the deadly midair collision last week.

An American Airlines plane prepares to land at Ronald Reagan Washington National Airport as crosses are seen in a makeshift memorial for the victims of the plane crash in the Potomac River Friday, Jan.

An American Airlines regional jet went down in the Potomac River near Ronald Reagan Washington National Airport.

Officials say the conditions of the Potomac River are complicating recovery efforts of the bodies of the 67 presumed dead in a mid-air collision between American Airlines flight 5342 from Wichita and a military Black Hawk helicopter.

Officials said they do not believe there were any survivors and continue to investigate the cause of the collision.

I don’t know of any other accident that has had this amount of impact on aviation but also in other industries,” one expert said of the 1982 crash.

As investigators look into the cause of Wednesday night's plane crash, pilots share their initial take on the collision.