Cargo doors wanted to be free, almost killed AA91 flight
American Airlines logo
June 12, 1972 at 19:00 local time, one aircraft belonged to the United States The airline's McDonnell Douglas DC-10-10 large wide-body passenger aircraft (registration number N103AA, delivered to American Airlines in January 1972, 6 months old at the time of the incident, is a new new aircraft that cannot be renewed. It is also the fifth production type DC-10) just took off from Detroit Metropolitan Wayne County Airport. The aircraft is flying from Los Angeles International Airport via Detroit Metropolitan Wayne County Airport and Buffalo Niagara International Airport. Flight AA96 at LaGuardia Airport in New York had 3 crew members, 8 crew members and 56 passengers on board at that time. The occupancy rate was less than one-fifth. Almost everyone could "lie down" and fly.
Detroit Metropolitan Airport overlooks
The captain of this flight was 52-year-old veteran pilot Bryce Eldon McCorming, the co-pilot was Pei Ji Whitney, the flight engineer is John. Although the crew all have certain qualifications in American Airlines, since the DC-10 has just been put into operation, their flight time on the DC-10 is not more than 75 hours. The flight attendant consisted of eight flight attendants, led by Cynthia Smith, one of the first black flight attendants of American Airlines.
Cynthia Smith
From Wayne County to Buffalo is the second segment of Flight AA96. The co-pilot Whitney controls the plane and Captain McCorming is in charge Supervise the instrument and control the throttle and be responsible for contacting the ground.
The AA96 flight
preparing to taxi to take off, a few minutes after takeoff, the AA96 flight steadily climbed to an altitude of 11,500 feet (about 3,500 meters). The seat belt indicator light went out immediately, and the flight crew released their seat belts from their seats and got up to prepare to provide service to the cabin. Chief Cynthia Smith walked to the back kitchen of the plane to prepare to pour some coffee for the passengers. As soon as she pressed the water button of the coffee machine, she heard a loud bang, and the plane shook violently.
"At that time, I was sitting in the seat, and the captain had just turned off the indicator light to fasten the seat belt. I got up and walked towards the kitchen. I was walking downhill because the plane was still climbing. Coffee, I turned on the switch, walked to the side, and something happened. I remembered that I fell because the plane was originally up and down, but suddenly up and down, I saw the drop-down locker fall down, and the contents in the bag It fell out, and I thought to myself: God, I thought I was going to die.”
Passenger Lorita Kaminsky recalled the scene in the cabin at that time:
“The plane went down immediately. Chong, and then the things on the plane hit my face, and my face was bleeding immediately (the wound was under her nose). My husband was anxious to find a flight attendant and asked them to take something to press the wound on my face to stop the bleeding. "
Aerial catastrophe footage: injured Lorita Kaminski
The rapid siren sounded in the cockpit, and the crew fell into chaos.
Captain McComing (hereinafter referred to as the captain): "What happened? (Strange, why is the captain always the first to ask this question every time I encounter something)?"
Vice Whitney Driving (hereinafter referred to as the co-pilot): "We hit something. One missing engine!"
Captain: "It is the second engine! I will control it!"
Captain Mai Kangming took over the control At the same time, the auto-throttle lever "automatically" jumped to "idling", causing flight AA96 to lose most of its propulsion and start to decelerate. After stabilizing the plane, Captain McCorming quickly pushed the throttle to full speed again. As the power of the No. 1 and No. 3 engines on the wings on both sides recovered, the stall warning in the cabin immediately stopped, but the plane was still shaking violently. More than that, other alarms continued to scream.
Co-pilot: "How is the hydraulic pressure?"
Captain: "It's all malfunctioning, I have made an emergency turn."
Flight engineer: "The rudder is stuck!"
Captain: "How about the elevator?"
Flight engineer: "There is still reaction, but the reaction is slow!"
Captain: "We have to return to Detroit."
American Airlines N103AA DC-10-10 drawn by our director The second view of the type passenger aircraft
At this time, the vertical tail rudder of flight AA96 was stuck in the right position, causing the aircraft to deflect to the right involuntarily. The crew could only bring the stick to the left as far as possible to compensate for the torque of the plane's deflection to the right, while adjusting the thrust of the No. 1 and No. 3 engines on both sides to keep the plane as straight as possible, and flying the AA96 flight back to Detroit crookedly.
Captain: "(Detroit Air Traffic Control) Center, this is American Airlines Flight 96, we have an emergency."
Detroit Center: "Received, American Airlines Flight 96, what's the situation?"
Captain: "The rudder is malfunctioning! We need to descend into the field."
Co-pilot: "It should be able to fly."
Detroit Center: "American Airlines Flight 96, please fly to the right. Heading 200."
Captain: "American Airlines 96 received. I can't fully control the direction, so I have to turn slowly."
Aerial catastrophe shot: the cargo compartment loses pressure and the cabin floor collapses In the cabin of AA96 flight
, Chief Smith noticed a large hole in the floor on the right side of the rear of the cabin. At a glance, he saw the cargo hold below, and the cargo door that should have been closed has disappeared. Counting the number of people in the cabin, it was found that there was no shortage, and it was soon confirmed that one flight attendant was missing in the bathroom. After a little peace of mind, Smith immediately organized a flight crew to transfer the few passengers in the cabin to the front of the cabin as much as possible, away from the back of the cabin. After arranging all this, Captain Smith connected the cockpit: "Captain, there is a big hole on the back of the plane!" Captain
: "Big hole?"
Smith: "Yes, captain. You Do you have any instructions?"
Captain: "Please prepare for an emergency landing."
Smith: "Yes, Captain!"
After ordering the crew chief, Captain McComing turned to ask Whittaker. Co-pilot: "What is the sinking rate?"
Co-pilot: "The sinking rate (per minute) is 1600 feet (approximately 487 meters)."
Captain: "The sinking rate is too high !"
Aerial catastrophe shot: AA96 flight
after the cargo door burst. In order to stop the sinking rate, the captain increased the engine thrust and controlled the sinking rate in time. 700 feet per minute (about 213 meters). Although this move increased the aircraft's approach airspeed to 300 kilometers per hour, it avoided the possibility of the aircraft crashing before reaching the runway.
Captain McComing turned on the captain's broadcast at this time: "Ladies and gentlemen, this is the captain's broadcast. I am the captain. At present, there is a minor problem with the aircraft and we have already controlled it. We will return to Detroit for emergency Landing.”
The captain’s tone was calm and calmed the panicked passengers in time. Passenger Lorita Kaminsky, who suffered serious facial injuries, recalled: “Captain McCorming’s tone was calm, like welcoming passengers to board the plane. The few minutes before I returned to Detroit was the longest time since my flight. , Because we think it is impossible to survive."
The atmosphere in the cockpit is still solemn.
Captain: "After grounding, I can't straighten the fuselage!"
Co-pilot: "Well, we have no choice!"
The plane arrived at Detroit Airport at a speed close to 300 For an emergency landing at a speed of kilometers per hour, the aircraft will uncontrollably deflect to the right as soon as the main wheel touches down. Soon after touchdown, the main landing gear on the right rushesOut of the track and ran into the lawn. Finally, after taxiing for a long distance, the aircraft successfully braked only 300 meters from the end of the runway.
Co-pilot: "It's okay, please turn off the engine."
Captain: "Turn it off."
The cabin was already cheered. All 67 people on American Airlines flight AA96 flight N103AA DC-10-10 survived.
Details of American Airlines N103AA DC-10-10 passenger plane drawn by our director 1
American Airlines N103AA DC-10-10 drawn by our director Airliner details 2
The details of American Airlines N103AA DC-10-10 aircraft drawn by our director 3
American Airlines N103AA DC- drawn by our director Details of 10-10 passenger plane 4
Appendix: American Airlines flight AA96 accident investigation
The National Transportation Safety Board (NTSB) inspected the accidental aircraft and found the cargo door on the left rear of the fuselage Flies without wings; the platform sinks due to air pressure, and a gap appears; the wires connecting the second engine and other control surfaces are broken due to the sinking of the platform, causing the aircraft to lose the control of the second engine during the flight. Control the elevator and rudder. But Captain McCorming adjusted the output power of the two still usable engines to steer the aircraft. Because Captain McCorming has received DC-10 simulation flight training, he can deal with this crisis. A similar technique was adopted by the crew at the time in the United Airlines Flight 232 Sioux City crash 17 years later (the same type was DC-10) (for details, please see our factory director The mortal situation for a man to live, recalling the United Airlines Flight 232 7.19 Sucheng air crash ).
Even though the plane was badly damaged, the plane finally made a forced landing in Detroit and saved all the passengers.
Aerial catastrophe shot: A coffin containing the remains fell from flight AA96 and landed at a position 30 kilometers away from the airport.
After the plane stopped, the pilot was able to view the plane In the case of damage, a large hole appeared in the cargo door of the passenger plane. At that time, if anyone was in this position, it would immediately "fly" out of the cabin. The investigators took over the subsequent work. They did not find any signs of collision or explosion. After checking the cargo, they found that the coffin (there was still the remains) in the cargo hold was missing. The location where they were found was 30 kilometers away from the airport. Cargo doors scattered behind the passenger plane were also found nearby. After inspecting the cargo door of the passenger plane, the investigator found that the design of the door was the chief culprit in the accident. Under normal circumstances, the cabin doors of jet airliners are opened from the outside to the inside, and the area of the door is larger than the area of the door frame. After the airliner is lifted up, the pressure in the cabin will increase as the altitude increases. Under the action, it will be embedded in the door frame. In order to expand the inventory volume of the McDonnell Douglas DC-10 passenger aircraft, the cargo door is designed to open outward. After the cargo door of the DC-10 passenger aircraft is closed, the lock hook will buckle the door latch of the fuselage door frame, and finally the porter will press the door lever to let the lock pin pass through the lock hook. The investigator did not find any major structural damage near the cargo door, but when further researching the door lock, it was found that the latch was not fully fastened, and the last "safety" lock pin did not click into the correct position. After questioning the porter on duty, the investigator found that even if the lock pin did not click into the correct position, the door rod outside the cabin could still be successfully pressed down, which also caused serious safety hazards to the cargo door.
AA96 flight cargo door that has been deformed and rolled up#
As the passenger plane climbs, the pressure difference between the cabin and the cabin gradually increases, The cargo door that is not completely locked will be torn by a strong force, and the cargo in the cabin will be sucked into the air after the door is separated. Explosive decompression will occur in the cabin, and things that are not fixed will be sucked out of the cabin. However, the occurrence of explosive decompression will not cause the plane to lose control. There must be other accidents on American Airlines Flight 96. The investigator carefully observed the structure of the aircraft and found that the design of the DC-10 passenger aircraft had a major safety hazard. After the cargo door was separated, the cabin floor collapsed due to excessive pressure. The collapsed location happened to be the cable connection of the flight control system. This also resulted in Captain McComming being only able to perform part of the aircraft's functions. American Airlines AA96 flight was also able to land safely thanks to Captain McComming’s superb driving skills. American Airlines Flight AA96 exposed the fatal design flaws of the DC-10 aircraft. The NTSB also clearly pointed out the problem with the cargo door and notified all airlines that purchased this type of aircraft. The accident also had a huge impact on McDonnell Douglas, but Unfortunately, McDonnell Douglas did not make timely and effective changes to the cargo door of the DC-10 aircraft.
successfully landed in Detroit, flight AA96 flight N103AA
NTSB issued a report, requesting McDonnell Douglas and its cargo door manufacturers to improve their cargo door design, such as adding at least one The small window is used for the ground crew to observe whether the lock hook behind the door has been locked. In addition, explosive decompression will cause the platform to sink, and it may also crush nearby lines. Therefore, NTSB also requested McDonnell Douglas to improve the floor design and increase ventilation holes to reduce similar risks.
However, the problems caused by this accident have not been satisfactorily resolved. Two years later, another DC-10 cargo door accident occurred on Turkish Airlines Flight 981. Unfortunately, all 346 passengers and crew on board were killed. This accident became the most tragic air crash in history until 1977. (For details, please refer to our director Tuji Airlines who died unjustly, and review the article on Turkish Airlines Flight 981 1974.3.3 Ermanonville Air Crash ) .
Many public opinions bombarded the aircraft manufacturer McDonnell Douglas after the incident. Some aviation authorities also pointed out that McDonnell Douglas ignored the lessons of the Windsor incident. Although McDonnell Douglas redesigned the cargo door design of the DC-10, it could not make up for the 346 lives on Turkish Airlines Flight 981. After being repaired, the
N103AA plane was put into service with American Airlines again, until it was retired from American Airlines after 1993. The aircraft was subsequently demolished at Goodyear Airport in Phoenix, Arizona in 2002.
The American Airlines flight AA96 accident was included in the second episode of the fifth season of the large-scale air disaster documentary "Fatal Design".
DC-10 performance data
Designer: Douglas Aircraft Company
Crew: 3 crew + 270 crew (standard)
Length: 55.5 meters
Wingspan: 50.4m
Height: 17.7m
Empty weight: 122951 kg
Maximum take-off weight: 259450 kg
Engine: Three General Electric CF6-50C2 turbofan engines , A single unit thrust 240.2 kN
Economic cruising speed: 908 kilometers per hour
Maximum range: 11685 kilometers
Maximum load range: 7505 kilometers
