On March 10, 2019, an Ethiopian Airlines flight bound to Nairobi, Kenya crashed six minutes after it took off from the airport in Addis Ababa. The pilot had reported that he was having problems flying and requested to land back at Addis Ababa. Before he could, the plane dropped off the radar and crashed. All of the 157 people on the plane died in the accident.
This tragic accident happened less than five months after the Indonesian Lion Air plane crash on October 29, 2018. During this incident, a plane carrying 189 people crashed into the Java Sea 13 minutes after takeoff, also killing everyone on board. These two plane crashes, in different countries and on different continents, are related. Both the planes that crashed were Boeing 737 Max 8s, a new model introduced to the market two years ago. About 350 of these planes are used worldwide, and the 737 Max is Boeing’s fastest selling aircraft.
The 737 Max was a rushed project resulting from pressure on Boeing to compete with a new Airbus model. Because the Max had repositioned engines, its aerodynamics were different than that of the previous 737, exposing it to certain risks inflight. In order to fix that problem, Boeing added an automated software system called the Maneuvering Characteristics Augmentation System, or MCAS for short. This program automatically maneuvers the nose of the plane up or down based on the external angle to prevent the plane from stalling. Both Boeing and the Federal Aviation Administration (FAA) decided not to inform pilots about MCAS.
There are problems with the MCAS which are now readily apparent. Jean-Paul Troadec, the head of France’s Aviation Accident Investigation Bureau, said a major flaw in the system is that it only relies on one sensor and is difficult to override. Thus, a single faulty sensor could doom the plane. Data recovered from the black box of the Lion Air plane crash revealed that, prior to the plane landing in the ocean, the software had pulled the plane’s nose down more than two dozen times due to incorrect sensor data. The pilot was not able to correct the adjustments, as the system would automatically reset itself every time a pilot tried to intervene.
There is also similar evidence that this system malfunctioned in the Ethiopian Air crash. In the debris from the crash, the jackscrew, which moves the stabilizers on the tail of the plane, was recovered. Experts say that the way the jackscrew was configured shows that the stabilizers were turned upward, which is what MCAS uses to tilt the nose of the plane downward.
There is overwhelming evidence that Boeing’s planes are to blame for the accidents. Both of the crashed flights had highly experienced crew members; the FAA requires commercial pilots to have at least 1,500 hours of flight experience. The pilot in the Ethiopian Airlines crash had clocked 8,100 hours and the pilot of the Lion Air flight had logged more than 5,000 hours. In spite of evidence of the MCAS’s faults, Boeing has maintained that even if the system had malfunctioned, emergency procedures should have been sufficient in stopping the crash.
After the Lion Air crash, Boeing finally informed pilots about the MCAS software and promised to update it by the end of the year. Those revisions have not manifested and the result is March’s Ethiopian Air plane crash – and 157 deaths. Boeing has since stated that they will release software revisions in the upcoming weeks and also implement a proper training program for pilots concerning how to react to the software in response to an emergency.
The changes that Boeing will implement are meant to target the aspects of the MCAS that caused the crashes. The software fix will include using a second sensor, in case the first one proves to be faulty. In addition, it will slow the rate at which the nose of the plane is adjusted downward and includes a fail safe in which the automated system will turn off if it faces resistance from the pilot. And, although Boeing claims that the changes to MCAS will “make an already safe aircraft even safer,” the fact that Boeing is releasing these changes at all is a tacit admission that MCAS was responsible for both plane crashes.
Since the Ethiopian Air crash, more than 30 countries all over the world have grounded their 737 Max 8 planes. The first country to ground the planes was China, followed by Indonesia, Singapore, Australia, and the European Union. Although late to the game, the United States eventually grounded the 737 Max 8, but the delay meant that, for the first time in aviation history, China set international aviation precedent, rather than the United States. The American decision to wait until March 13 to ground its 737 Max 8s and 9s damaged the FAA’s credibility within the international community – especially in light of the fact that Boeing has all but declared that they are responsible for the deaths of 346 people.