What happened
On February 9, 1998, an American Airlines flight arriving from Kansas City International Airport was performing a Category II instrument landing system approach to runway 14R at Chicago O'Hare International Airport. The aircraft, a Boeing 727-223 registered as N845AA, encountered daylight instrument meteorological conditions during its final approach.
During the descent, the aircraft impacted the ground before reaching the runway threshold. There were 116 passengers, 3 flight crewmembers, and 3 flight attendants on board at the time of the impact. The accident resulted in 23 total injuries, consisting of 22 passengers and one flight attendant who sustained minor wounds. While the aircraft suffered substantial damage, there were no fatalities.
Findings
Investigations into the incident determined that the primary reason for the crash was the failure of the flight crew to manage the aircraft's pitch attitude correctly for either a landing or an aborted approach. The investigation also identified contributing factors related to the aircraft's behavior during the final stages of the approach, specifically noting that divergent pitch oscillations occurred due to an incorrect autopilot desensitization rate.