American Airlines Flight 191: The Takeoff from Chicago O’Hare and the Catastrophic Failure That Followed Seconds Later
The aircraft was accelerating down the runway at Chicago O’Hare International Airport, carrying passengers who expected an ordinary journey. For the people on board, May 25, 1979, began like countless other travel days: luggage had been stowed, seats occupied, and the familiar sounds of an aircraft preparing for departure filled the cabin. Outside, the aircraft gathered speed, approaching the moment when its wheels would leave the ground.
Then, within seconds of takeoff, a catastrophic mechanical failure transformed the flight into one of the most devastating disasters in American aviation history.
American Airlines Flight 191, a McDonnell Douglas DC-10 bound for Los Angeles, lost its left engine assembly during takeoff. The engine and its mounting structure separated from the aircraft, damaging important systems and creating a sudden, dangerous change in the airplane’s aerodynamic behavior. The aircraft lifted off, but it could not continue safely. It rolled, descended, and crashed shortly after leaving the runway area.
All 271 people aboard were killed, and two additional people on the ground died, bringing the total loss of life to 273. The disaster shocked the public, devastated families, and raised urgent questions about aircraft maintenance, engineering, airline procedures, and the way potentially dangerous mechanical problems were identified and addressed.
But the story of Flight 191 is more than a sequence of terrible moments. It is also a case study in how a failure during maintenance can become a catastrophe in the air, why a seemingly small change in an aircraft’s behavior can have consequences far beyond what passengers can see, and how investigators reconstruct events that unfold in seconds.
The official investigation uncovered a crucial chain of mechanical and operational failures. Understanding that chain helps explain why the aircraft was unable to recover—and why the disaster became such an important turning point in discussions about commercial aviation safety.
To understand what happened, we must return to the runway at O’Hare, follow the aircraft through its final seconds, and then examine the maintenance decisions and engineering details that investigators identified as central to the tragedy.
The Flight That Began Like Any Other
American Airlines Flight 191 was a scheduled passenger service operating from Chicago O’Hare International Airport to Los Angeles International Airport on May 25, 1979. The aircraft was a McDonnell Douglas DC-10-10, a wide-body jet powered by three engines: two mounted beneath the wings and a third positioned at the rear of the fuselage near the base of the tail.
The DC-10 had been designed to carry large numbers of passengers over long distances. Its wide cabin, three-engine configuration, and long-range capabilities made it a significant aircraft in the development of commercial air travel during the 1970s.
On that late-May afternoon, passengers boarded Flight 191 expecting to travel across the United States. The crew prepared the aircraft for departure, and the normal checks and procedures associated with a scheduled flight took place. Nothing about the passengers’ routine preparations could have revealed the chain of events that was about to unfold.
The departure runway was long enough for the aircraft to accelerate and reach the speed required for takeoff. As the engines produced thrust, the DC-10 moved down the runway, gathering the energy needed to become airborne.
For pilots, the takeoff phase is one of the most demanding parts of a flight. The aircraft must accelerate, respond to control inputs, and transition from ground movement to flight within a carefully managed sequence. Pilots monitor engine performance, airspeed, and the aircraft’s response, while following established procedures for the departure.
A serious malfunction during this phase presents a particularly difficult challenge. The aircraft may be moving too quickly for an ordinary stop to be simple, yet it may not have enough altitude for the crew to diagnose an unfamiliar problem and recover from it.
That was the situation Flight 191 encountered.
As the aircraft accelerated and lifted from the runway, the left engine assembly separated from the wing. The failure was not merely the loss of an engine’s thrust. The departing assembly damaged other components, including systems needed to maintain the aircraft’s expected behavior after takeoff.
The airplane continued into the air, but the damage had fundamentally changed the situation. The pilots were faced with an aircraft that no longer responded as expected, at a moment when altitude and time were extremely limited.
What followed would become the central focus of the National Transportation Safety Board’s investigation.
The Seconds After Liftoff: Why the Aircraft Could Not Recover
The sequence that followed the engine separation was extraordinarily short. According to the investigation, Flight 191 climbed to approximately 325 feet above the ground before beginning a steep roll to the left. The aircraft continued rolling until its wings passed beyond the vertical position, and its nose dropped below the horizon.
For an aircraft only a short distance above the airport, that left almost no time to identify the problem, understand its effects, and respond.
The engine assembly did not simply fall away without affecting anything else. Its separation damaged systems in the left wing area, including hydraulic lines and electrical components. Those failures changed the behavior of the aircraft and removed important warning indications that the pilots would normally use to recognize an unsafe condition.
To understand the significance, it helps to look at two parts of an airplane that passengers rarely think about: leading-edge slats and stall-warning systems.
What Are Leading-Edge Slats?
Leading-edge slats are movable aerodynamic surfaces fitted to the front edge of a wing. They help the wing generate lift at lower speeds, particularly during takeoff and landing.