All 64 people aboard an American Airlines jet that collided with an Army helicopter were feared dead in what was likely to be the worst U.S. aviation disaster in almost a quarter century, officials said Thursday.

The midair collision over the Potomac River on Wednesday brings back chilling memories of another tragedy in the same waters more than four decades ago—when Air Florida Flight 90, bound for Fort Lauderdale-Hollywood International Airport,

Several federal and state investigations have been launched after an American Airlines flight and a military helicopter collided near Ronald Reagan Washington National Airport and fell into the Potomac River,