Case Study: Two plane crashes of Boeing 737 MAX passenger airliner on the Lion Air Flight 610
- EXECUTIVE SUMMARY
This case study was made to provide a comprehensive analysis involving two plane crashes of Boeing 737 MAX passenger airliner on the Lion Air Flight 610 on October 29, 2018, and Ethiopian Airlines Flight 302 on March 10, 2018.
To keep up with the competition in the airline industry, the world’s largest commercial aircraft manufacturer, Boeing, needs to make more economic flight operations than other competitors such as the Airbus company. Boeing made a move to modify and enhance the Boeing 737’s fuel efficiency. The new upgraded version of it was called Boeing 737 MAX.
The difference between the new and old versions is that the Boeing 737 MAX has a Maneuvering Characteristics Augmentation System (MCAS), split winglets, a CFM LEAP-1A engine, and a chevron to reduce the aircraft noise.
The first plane crash involving the Boeing 737 MAX occurred last October 29, 2018, involving the Lion Air Flight 610. The domestic flight only lasted for 12 minutes after takeoff. The airplane crashes to the sea, killing all 189 passengers and crews.
A day before the incident, the airplane experienced repeated nose-down maneuvers, putting the aircraft in an “un-airworthy” condition. Hence, the plane was accepted to continue its service. The digital flight data recorder detected an unusual difference in the angle of attack during takeoff on the day of the accident. Few flight officers tried to analyze the problem, but the pilot was unsure about the new system. As time passes, they noticed the difference output of the digital flight data recorder between the plane’s system and the control tower’s data.
After takeoff on the day of the accident, the flight officers reported to the air traffic controllers about certain flight control problems as the plane continue to descend in altitude. The control tower told the officers that their current altitude was very low and improper. The pilot then retracted the flaps, and the aircraft suddenly starts pointing its nose down. This automatic change in the control system does not allow pilots to maneuver it for 10 seconds. This scenario happened again but this time, the plane descends up to 3,200 feet per minute.
Since the pilot cannot control the system, they decided to extend the flaps by five degrees. The aircraft goes back to the control of the flight officers for a few seconds and then its nose points down again a couple of times. This automatic control is due to the Maneuvering Characteristics Augmentation System (MCAS) is equipped in the aircraft. This anti-stall system pitch automatically pitches the nose down without allowing the pilots to control it. Few minutes have past and the communication between the pilots and the control tower was disrupted. This automatic pitch-down condition of the system led to the aircraft crashing on the coast of the island of Java.
Search and rescue operations immediately deploy involving three ships and helicopters to cover the coast. Afterward, the rescue team confirmed that there were no survivors of this fatal crash.
Few months after the accident, the Boeing 737 MAX – Ethiopian Airlines Flight 302 was scheduled to have an international flight on March 10, 2019, with 157 people on board. The flight is from Addis Ababa Bole International Airport in Ethiopia all the way to Jomo Kenyatta International Airport in Nairobi, Kenya.
Few minutes after the departure, the same issues in the Lion Air Flight 610 plane crash occurred in the Ethiopian Airlines Flight 302, the system shows different values of the angle of attack, airspeed, and altitude. As a counterattack, the pilot retracted the flaps to stop the automatic pitch-down of the plane. The flight control problems were reported to the air traffic controllers (ATCs) for further assistant. The ATCs instructed the crew to turn at 260 degrees but the MCAS system does not allow the pilot to control the aircraft. Thus, the automatic pitch-down of the plane continues to happen, causing the aircraft to crash on the land of the Addis Ababa southeast terrain area killing all people on board.
The Lion Air Flight 610 fatalities are listed below:
- Total Occupants: 189 people
- Passengers: 181
- Crew: 8
- Fatalities: 189
- Survivor 0
The Ethiopian Airlines Flight 302 fatalities are listed below:
- Total Occupants: 157 people
- Passengers: 149
- Crew: 8
- Fatalities: 157
- Survivor 0
Both flights are concerned with the same design of Boeing 737 MAX. The following problems that happened on both flights are:
- The digital flight data recorders show different output on the pilot, flight officers, and air traffic controllers’ screens.
- The nose of the aircraft automatically points down and the pilots could not control it.
- The MCAS is equipped as an anti-stall system to the new Boeing 737 MAX design, but the pilots are not aware of it. The system’s malfunction causes the aircraft to automatically points down.
- The flight crews mismanaged engine thrust and airspeed.
After the accidents, the following reports were made as the cause of the fatal plane crashes:
- The new design of the Boeing 737 MAX is not efficient.
- The FAA managers pushed the agency’s engineers to refuse safety assessments to Boeing to speedily approve the resulting analysis.
- Boeing did not manage proper training for the flight crews about the MCAS integration.
- The manuals did not include anything about the MCAS.
- The maintenance logbook showed that the flight data recorder malfunctioned many times before the accident and the company allowed it to operate.
- The angle of attack sensors and flight data recorder was defective.
The problems found on Lion Air Flight 610 and Ethiopian Airlines Flight 302 are due to the design of the Boeing 737 MAX. The larger CFM LEAP-1A engine on the new model of the Boeing 737 cannot fit under the wings and the company decided to move forward the engines causing it to increase the angle of attack and will lead the aircraft to stall and crash.
Boeing installed the Maneuvering Characteristics Augmentation System to counteract the stalling problem. It forces the nose of the aircraft to point down to eradicate the stalling moments. MCAS monitors the maneuver of the aircraft, and it activates to automatically levels the pitch of the aircraft when an aircraft reaches its AOA limits.
After Boeing releases the Boeing 737 MAX, they rejected the provision made by the pilot testers, saying that the MCAS is not efficient and may result in further flight disturbance. Also, the company hid the information about equipping the MCAS on the aircraft. They did not mention it in their manuals and to the pilots. The engineers who designed the MCAS program the system to rely on a single sensor instead of multiple types of equipment to avoid extra pilot training. The faulty operation of the FAA managers is one of the reasons why the design was rushed engineered to save time and money.
There are possible solutions to avoid certain flight problems like this:
- Do not rush the process of designing the aircraft and undergo proper safety procedures.
- Make thorough training for the flight crews to deeply understand the aircraft systems.
- Include all necessary details about the aircraft in the manual.
- Make multiple sensors in case one of them broke.
- Do not rush the FAA’s certification.
- Position the engines properly.
- Consider all aerodynamic factors in designing the aircraft.
- Do thorough pre-flight screening on the aircraft’s system and engines.
- Do not instantly approve new systems without asking recommendations from other aviation authorities.
Boeing redesigned the Boeing 737 with bigger engines, but it can’t fit under the wings, so it was moved forward. Because of this, the aircraft will stall too high that will lead to a plane crash. To counteract this stalling, the MCAS was integrated into the system to automatically pitch down the stalling aircraft.
The incident involving the Boeing 737 MAX on the two-plane crash (Lion Air Flight 610 and Ethiopian Airlines Flight 302) was due to the MCAS control. The pilot was not able to control the continuous pitch down of the plane that causes the planes to crash.
These accidents are due to Boeing’s not proper pilot training and not informing them about the MCAS. This system is also not included in the manual. Some sensors and data recorders are also found to be deflected before the flight departure of both accidents, but it was allowed by the authority to fly.
Designing an aircraft must have adequate time and budget for it to be economic and safe. It should undergo proper tests and procedures to access the capabilities and limitations of the aircraft.
It is important to consider all aerodynamic forces in designing the aircraft. The placing and size of the engines is a big concern in designing the aircraft. This counteracts flutter caused by aerodynamic forces. Bigger engines have more fuel efficiency but placing it too far forward will cause the aircraft to stall.
If anti-stall systems are integrated into the system, they should be accessed thoroughly by different aviation experts. The MCAS as an anti-stall system should be introduced to the flight crews and indicate to the manual for better understanding. Proper training of the flight crews is a must to avoid accidents like the plane crash of Lion Air Flight 610 and Ethiopian Airlines Flight 302.
All findings during the pre-flight inspections should be considered and problems should be addressed before allowing the aircraft to operate. Flight equipment like the angle of attack sensor and flight data recorder should be check if it is properly working before the flight. It is recommended to have backup systems and extra sensors in case of emergency.
During the designing of the aircraft, engineers are tasked to create an aircraft that all the rules and safety regulations. They are the one who will create the primary and backup systems and make sure that it is safe and efficient.
The Boeing company must allocate sufficient budget and certifications for the aircraft after it was designed and engineered. They need to reach out to other aviation experts to further analyze the design of the aircraft. Proper FAA certification and standards must be met before allowing it to operate.
The company’s management should conduct thorough training for the flight crews especially the pilots for them to analyze and get familiar with the system. The management must provide a backup plan and systems in case of an emergency.
Before the flight, an inspection must be done by the pilot and other officers to make sure that all systems are properly working. The management should also conduct periodic inspections and modifications of the system, equipment, and engines.
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