The last time a passenger died in a commercial plane crash in the United States was nearly 16 years ago. That is, until the shock collision between a commercial Bombardier CRJ700 and a military Black Hawk created an explosion over the Potomac River, bringing Washington, D.C., to a standstill.

While we still have much to learn about the ensuing tragedy, including the death toll, the facts on their own are almost unthinkable. In the single most restrictive airspace in the country, the Black Hawk crashed into American Airlines Flight 5342 from Wichita as it was moments away from touching down on the tarmac of the Ronald Reagan Washington National Airport. There’s no evidence or allegation of foul play, but the coincidences are as horrifying as they are extraordinary.