American Airlines Flight 191

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American Airlines Flight 191

Michael Laughlin took this famous photograph from a parking lot at the O'Hare airport. It depicts Flight 191 in an unrecoverable bank moments before the crash. Its No. 1 engine had been severed on the runway.
Accident summary
Date	May 25, 1979
Type	Maintenance error causing loss of Engine 1, combined with pilot's failure to correct
Site	Des Plaines, Illinois
Passengers	258
Crew	13
Fatalities	273 (including 2 on the ground)
Survivors	0
Aircraft type	DC-10
Operator	American Airlines
Tail number	N110AA
Flight origin	O'Hare International Airport
Destination	Los Angeles International Airport

American Airlines Flight 191, from O'Hare International Airport in Chicago, Illinois, to Los Angeles International Airport, crashed during take-off on May 25, 1979 at approximately 15:04 CDT. The McDonnell Douglas DC-10-10 had 258 passengers and 13 crew on board. There were no survivors, and two persons on the ground were also killed.^[1] It remains the deadliest single airliner accident on U.S. soil.^[2]

Contents 1 Flight and cabin crew 2 Accident 3 Witnesses, media response 4 NTSB investigation 4.1 Failure Detail 4.2 Cockpit recorder, air traffic controller 4.3 Maintenance history 4.4 Simulations 5 Aftermath 6 Victims 7 History and media 8 See also 9 Notes 10 External links

[edit] Flight and cabin crew

The captain was veteran Walter Lux, 53. His first officer was James Dillard, 49, and the flight engineer was Alfred Udovich, 56. Captain Lux was one of the most experienced DC-10 pilots in the airline, and he had been flying the DC-10 since its introduction 8 years earlier. He had around 22,000 hours logged. First Officer Dillard and Flight Engineer Udovich were also very experienced, with nearly 25,000 flight hours between them.^[3][4] The ten flight attendants were Linda Bundens, Pauline Burns, James Dehart, Carmen Fowler, Catherine Hiebert, Carol Ohm, Linda Prince, Michael Schassburger, Nancy Sullivan, and Sally Jo Titterington.

The aircraft had been delivered new to American Airlines on February 25, 1972. It had logged over 20,000 hours of flight over seven years at the time of the crash. ^[5]

[edit] Accident

The weather on May 25 was clear, with a northeast wind at 22 knots (41 km/h). At 14:50 CDT, Flight 191 (N110AA) was cleared to taxi to runway 32R (Right) and at 15:02, the flight was cleared for takeoff and began its roll down the runway. ^[6] Takeoff was normal until air traffic controller Ed Rucker witnessed the number one engine (left wing) separate from the aircraft. The engine flipped over the wing and fell onto the runway. The aircraft continued in a normal climb momentarily to around 350 feet AGL, as leaking fuel and hydraulic fluid spewed a vapor trail.

Such an incident is theoretically survivable in a DC-10; the shift in center of gravity and mean aerodynamic chord were within tolerances, and the aircraft could have landed safely if the engine loss had not caused other failures. In subsequent flight simulation testing, with all known collateral failures included in the simulation, only pilots who were aware of Flight 191's specific problems were able to recover successfully. ^[7] Newspapers later reported that if the pilots had retracted the flaps, the plane could have recovered.

The experienced pilots immediately knew that they had lost an engine, but they could not have been sure that it had literally fallen off, or if it had damaged anything. The crew aimed to reduce speed from 165 knots (306 km/h) to the recommended engine-out climb speed of 153 knots (283 km/h), but the engine separation had severed the hydraulic lines that controlled the aircraft's leading-edge wing slats (retractable devices that decrease a wing's stall speed during takeoff and landing). Further, the missing engine had ripped 3 feet of the leading edge of the wing with it, including the hydraulic, and electrical power supplies to the captain's instruments — notably stall warning, slats disagreement, and stick shaker, which were only available to the captain and not replicated in the first officer's instruments. (McDonnell-Douglas offered a copilot stick shaker, but AA had not purchased this option.) To reach a backup power switch, the flight engineer would have needed to rotate his seat, release his safety belt and stand up, part of the abnormal situation routines, not the take-off emergency procedure. This meant that the pilots were unaware of the aircraft's true condition. DC-10 aircraft engines are not visible from the cockpit windows, and the control tower did not inform the flight crew of what they had seen.

As the hydraulic fluid bled away, the force of the moving air over the slats on the left wing caused them to retract, resulting in a significant loss of lift on the left wing and above all an untrimmable rolling moment to the left, because of that asymmetric lift. The aircraft entered an uncontrollable 112-degree left bank and pitched below the horizon from around 325 feet (99 m), slamming into an open field approximately 4,600 ft (1,400 m) from the end of the runway northwest of the airport at 15:04 CDT after about 31 seconds in the air.

The plane struck a hangar of the old Ravenswood Airport that was in use by the Courtney-Velo Excavating Company at 320 W Touhy Avenue, with the fuselage cutting a trench into the empty former airfield to the east of a mobile home park. With an unused load of jet fuel, the crash generated a large fireball, causing a plume of smoke that could be seen from the downtown Chicago Loop. The aircraft disintegrated and burned, and all 271 people on board were killed by the impact and subsequent fire, which also killed two workers at the Courtney-Velo repair garage and severely burned two more. Some wreckage was thrown into the nearby mobile home park, where three residents were injured and five trailers and several automobiles were damaged.

[edit] Witnesses, media response

The disaster and investigation was quickly and thoroughly covered by the media assisted by new news gathering technologies. The public impact of the accident was increased by dramatic amateur photos taken of the incident, which were published on the banner of the Chicago Tribune the following day.^[8]

Officials at the destination airport, Los Angeles International, were careful to keep the arriving news media away from passenger relatives who were waiting for Flight 191.

There were some early reports that a collision of a small plane had been involved in the crash. This apparently resulted from the discovery of small aircraft parts among the wreckage at the crash site. The parts were determined to have originated on the ground from the former Ravenswood Airport, a former general aviation facility which had been out of service for a few years. An owner there had been selling used aircraft parts from the former hangar building.^{[citation needed]}

The crash of flight 191 brought criticism from the media because it was the fourth fatal accident involving a DC-10 at the time, totaling 662 fatalities. The separation of engine #1 from its mount raised widespread concerns about the safety of the DC-10.

[edit] NTSB investigation

The findings of the investigation by the National Transportation Safety Board (NTSB) were released on December 21, 1979.^[1] It revealed the probable cause to be attributable to damage to the left wing engine pylon that occurred during an earlier engine change at American Airlines's aircraft maintenance facility in Tulsa, Oklahoma on March 29 and 30, 1979. ^[1] Evidence came from the flange, a critical part of the pylon assembly.

[edit] Failure Detail

The separation of the engine severed electrical wiring and hydraulic lines which were routed through the leading edge of the wing. The damage to the lines caused a loss of hydraulic pressure, which in turn led to uncommanded retraction of the outboard slats in the port wing. The DC-10 design included a back-up hydraulic system which should have been enough to keep the slats in place; however, both lines are too close together, a design also used on the DC-9. There should have been enough fluid to keep the slats extended, so investigators wanted to know why they were never re-extended by the pilot. The answer came from the end of the recording on the cockpit voice recorder. The number 1 engine powered both the recorder and the slat warning system, which left the pilot and co-pilot with no way of knowing about the position of the slats. Investigators examined the flight data recorder to see what occurred after the engine detached. The procedure called for the captain to go to V2 (standard safety takeoff speed for that plane) which he did perfectly, but investigators found that it said nothing about incidents where the speed was already above V2, as it was in this case. Therefore, the pilot had to reduce speed to get to V2. Simulator tests were done to see if this made a difference; 13 pilots followed the procedure 70 times and not one was able to recover. The NTSB concluded that reducing speed when the slats are back may actually have made it more difficult for the pilot to recover control of the aircraft. When a DC-10 is about to stall it gives two warnings: The first is the stick-shaker which causes the yoke to vibrate, and the second is a warning light that flashes. These combined warnings should have alerted the pilots to increase speed immediately. American Airlines had chosen to have the stick-shaker on the pilot's side only, but the stick-shaker did not operate because the missing left engine ripped out its electrical power supply. In the event of an of the electric power supply being lost, it is possible for the flight engineer to switch the pilot's controls to a backup power supply. However, investigators determined that in order for him to access the necessary switch, the engineer would have had to unfasten his seat belt, stand up, and turn around.

The DC-10 hit the ground with a bank of 112°, and at a nose-down attitude of 21°. The NTSB concluded that given the circumstances of the situation, the pilots could not be reasonably blamed for the resulting accident.

[edit] Cockpit recorder, air traffic controller

Although the plane's cockpit voice recorder was powered by the severed number #1 engine, it picked up one of the crew saying "..Damn.." before recording ceased.^[9] The control tower voice recorder recorded a controller contacting the airliner when he witnessed the engine separation just after take-off, but the crew didn't answer as they were too busy trying to save the aircraft. The recording begins with the controller talking without transmitting on the frequency: "Look at this, look at this, he blew off an engine. Equipment, I need equipment, he blew an engine. Oh, shit!" The controller then transmitted, "And American one, uh, ninety-one heavy, you wanna come back and to what runway?" Without keying the mic, the controller can be heard: "He's not talkin' to me ...yeah, he's gonna lose a wing. There he goes, there he goes..." Another controller in the tower remarked, "I need to be relieved."

[edit] Maintenance history

The aircraft was found to be damaged before the crash.^{[citation needed]} Investigators looked at the plane's maintenance history and found that its most recent service was eight weeks before the crash. The pylon was damaged due to an engine removal procedure. The original procedure called for removal of the engine prior to the removal of the engine pylon. To save time and costs, American Airlines, without the approval of McDonnell Douglas, had begun to use a faster procedure.^{[citation needed]} Mechanics were instructed to remove the engine with the pylon as one unit. A large forklift was used to support the engine while it was being detached from the wing. This procedure was extremely difficult to execute successfully, due to difficulties with holding the engine assembly straight while it was being removed.

This method of engine-pylon removal was used to save man hours and was encouraged despite differences with the manufacturer's specifications on how the procedure was supposed to be performed. The accident investigation also concluded that the design of the pylon and adjacent surfaces made the parts difficult to service and prone to damage by maintenance crews. According to the History Channel,^[10] United Airlines and Continental Airlines were also using a one-step procedure. After the accident, cracks were found in the pylon bulkheads of DC-10s in both fleets.

The procedure used for maintenance did not proceed smoothly. If the forklift was in the wrong position, the engine would rock like a see-saw and jam against the pylon attachment points. The forklift operator was guided by hand and voice signals; the position had to be spot-on or could cause damage, management was aware of this. The modification to the aircraft involved in Flight 191 did not go smoothly; engineers started to disconnect the engine and pylon but changed shift halfway through; when work continued, the pylon was jammed on the wing and the forklift had to be re-positioned. This was important evidence because, in order to disconnect the pylon from the wing, a bolt had to be removed so that the flange could strike the clevis. The procedure used caused an indentation that damaged the clevis pin assembly and created an indentation in the housing of the self-aligning bearing, which in turn weakened the structure sufficiently to cause a small stress fracture. The fracture went unnoticed for several flights, getting worse with each flight that the plane had taken. During flight 191's takeoff, enough force was generated to finally cause the pylon to fail. At the point of rotation, the engine detached and was flipped over the top of the wing.

The loss of the engine by itself should not have been enough to cause the accident. During an interview on Seconds From Disaster, former NTSB investigator Michael Marx mentioned there were other incidents where the engine fell off, yet they landed without incident. Flight 191 would have been perfectly capable of returning to the airport using its remaining two engines, as the DC-10 is capable of staying airborne with any single engine out of operation. Unfortunately, several other factors combined to cause a catastrophic loss of control.

[edit] Simulations

Thirteen pilots participated in the flight's simulation.^[1] They were briefed on the flight's profile, and the simulation was programmed to repeat the flight's configuration after the loss of the number 1 engine. Variables included different scenarios pertaining to hydraulic failure and stick shaker functionality.^[1] For the tests, 70 simulated flights and 2 landings were conducted. In all cases, the flight for 191 were duplicated as each pilot repeated the control inputs per American Airline's flight manual.^[1]

[edit] Aftermath

Problems with DC-10s were discovered as a cause of the accident, including deficiencies in both design specifications and maintenance procedures which made damage very likely. In response to this incident, American Airlines was fined by the United States government $500,000 for improper maintenance procedures^[11].

Since the crash happened just before a Western Airlines DC-10 crashed in Mexico City and five years after a Turkish Airlines DC-10 crashed near Paris, the FAA quickly ordered all DC-10s to be grounded until all problems were solved. ^[12] The crash of another DC-10 in November 1979, Air New Zealand Flight 901, would only add to the DC-10's negative reputation at the time - however, Flight 901 was caused by several human and environmental factors not related to the airworthiness of the DC-10, and the aircraft was later completely exonerated in that incident.

Although McDonnell Douglas employees participated in an "I'm proud of the DC-10" campaign, the company's shares fell more than 20% following the crash of Flight 191. The DC-10 itself acquired a bad reputation, but ironically it was often caused by poor maintenance procedures, and not design flaws. In 1997 the McDonnell Douglas company was taken over by its rival, Boeing, which moved their corporate headquarters from Seattle to Chicago.

Despite the safety concerns, the DC-10 went on to outsell its closest competitor, the Lockheed L-1011 TriStar, by nearly 2 to 1. This was due to the L-1011's launch being delayed, the introduction of the DC-10-30 long range model without a competing TriStar variant, and the DC-10 having a greater choice of engines (the L-1011 was only available with Rolls-Royce engines, while the DC-10 could be ordered with General Electric or Pratt & Whitney engines). The DC-10 program also benefited from obtaining a U.S. Air Force contract to develop a long-range refueller, which culminated in the KC-10 Extender. Lockheed had no such support for the TriStar, and halted production in 1982.

[edit] Victims

Some of the victims in the crash of Flight 191 were:

• Itzhak Bentov, a biomedical inventor (the cardiac catheter), New Age author (Stalking the Wild Pendulum and A Cosmic Book) and kundalini-researcher;

• Judith Wax and her husband, Sheldon Wax. Judith Wax frequently contributed to Playboy (of which Sheldon was managing editor), notably the annual "Christmas cards" piece that "presented" short satirical poems to various public figures. It was reported at the time that in her 1979 book Starting in the Middle, she had written about her fear of flying.^[13] The magazine's fiction editor Vicki Haider also died in the crash.^[14][1]

• Several members of the American Booksellers Association who were on their way to their annual convention at the Los Angeles Convention Center, where they were to have a joint party organized by Playboy founder Hugh Hefner;

• Several senior executives of the accounting firm Coopers & Lybrand;

• Sheila Charisse, daughter-in-law of movie actress Cyd Charisse;

• Leonard Stogel, Music business producer/executive for Cal Jam, The Cowsills, Sam the Sham and other music groups;

[edit] History and media

The cable/satellite TV channel The History Channel produced a documentary on the crash,^[10] and an episode from Seconds From Disaster titled "Chicago Plane Crash"^[11] (also known as "Flight Engine Down") detailed the crash and included footage of the investigation press conferences.

Following the crash and the media attention towards the DC-10, American Airlines replaced all "DC-10 LuxuryLiner" titles with a more generic "American Airlines LuxuryLiner".^[15]

The flight number "191" has been associated with numerous crashes and incidents over the years. It has even prompted some airlines to stop the use of this number.^{[citation needed]}

The crash was used to hide the disappearance of Diane Chorba. She was murdered in the days surrounding the flight and her daughter was told that she had been on the plane. Cook County medical examiners assigned the task of identifying the crash victims, later disproved this. Clarence Bean, Jr. was found guilty of the murder in 2001.^[16]

[edit] See also

• List of accidents and incidents on commercial airliners
• China Airlines Flight 358
• El Al Flight 1862
• Spanair Flight 5022
• Northwest Airlines Flight 255
• Delta Air Lines Flight 191
• Air safety

[edit] Notes

[edit] External links

Wikimedia Commons has media related to: American Airlines Flight 191

• Accident description at the Aviation Safety Network
• FAA "Public Lessons Learned from Accidents -American Airlines Flight 191"{{dead link|date=December 2009}
• PlaneCrashInfo.Com - American Airlines Flight 191
• Flight 191 Remembered (Fox Chicago website){{dead link|date=December 2009}
• Pre-crash pictures from Airliners.net
• A site in the works (as of 5/25/09) in remembrance of those who died^{[dead link]}

v • d • e ← 1978 Aviation accidents and incidents in 1979 1980→ Air Rhodesia Flight 827 (February 12) — CG-1432 Crash (February 18) — TWA Flight 841 (April 4) — American Airlines Flight 191 (May 25) — Air New England Flight 248 (June 17) — Garuda Fokker F28 crash (July 11) — Dan-Air Flight 0034 (July 31) — Comair Flight 444 (October 8) — American Airlines Flight 444 (November 15) — PIA Flight 740 (November 26) — Air New Zealand Flight 901 (November 28) — Turkish Airlines Ankara crash (December 23) Bold indicates incidents resulting at least 50 deaths (current article is always in bold) Orange color indicates the deadliest incident in 1979

Coordinates: 42°0′35″N 87°55′48″W / 42.00972°N 87.93°W / 42.00972; -87.93