PSA Flight 182 was the deadliest crash in US aviation history until the flight that left which Chicago airport a year later?
PSA Flight 182: Pacific Southwest Airlines (PSA) Flight 182 was a Boeing 727-214 commercial airliner, registration, N533PS that collided with a private Cessna 172 light aircraft, registration, N7711G over San Diego, California, at 9:01 am on Monday, September 25, 1978. American Airlines Flight 191: American Airlines Flight 191 was a regularly scheduled passenger flight operated by American Airlines from O'Hare International Airport in Chicago to Los Angeles International Airport. American Airlines Flight 191:  A McDonnell Douglas DC-10-10 used for this flight on May 25, 1979, crashed moments after takeoff from Chicago.
O'Hare International Airport