Mind Considering Aircrafts Safe? (MCAS)

By Ram Charan

Contrary to popular belief, planes are not falling out of the sky. However, the newest model of the Boeing 737, the 737 MAX 8, has recently headlined the news for problems with one of the aircraft’s incorporated automated systems: the Maneuvering Characteristics Augmentation system (MCAS).

A Short History of the MAX 8

After the aircraft was modified through the addition of more environmentally friendly CFM international Leap 1-B engines, the 50-year-old base model of the 737 was fundamentally changed. The new engines weighed 891 pounds more than previous engines, and the wings had to be moved along the fuselage. The clearance of the aircraft had to be raised eight inches to successfully integrate the newly acquired engines.

For this reason, Boeing pioneered the MCAS system, a system meant to combat the natural drag of the aircraft and its fundamental flaw. The program is a seemingly temporary fix, and it has come under the watchful eyes of the aviation community in a spate of recent crashes of the 737 MAX 8. Members of Boeing have been asked to present themselves in court and a full-scale investigation into the viability of the aircraft before it was approved by the FAA is taking place.

The plane was designed to compete with the Airbus A320neo family, a string of aircraft that are also equipped with more fuel-efficient engines. Airbus instead uses Leap 1-A engines and its key selling point is environmentally friendly and more fuel-efficient travel. The Airbus A320neo family was developed ahead of the 737 MAX 8 and was ready to sell well before Boeing’s new initiative for economical travel. To prevent Airbus from getting ahead in sales, Boeing rushed the 737 MAX 8 into production.

Two Crashes.  No Survivors.

Two 737 MAX 8’s, within a year, crashed under similar circumstances. Both black boxes of the aircraft recorded sudden altitude changes, and they both were destroyed within mere minutes of their takeoff.

The first crash was that of Lion Air Flight 610 from Jakarta to Panal Pinang. The aircraft suffered from 11 minutes of continuous altitude change through which the pilots tried to correct the course of the aircraft 12 times right after takeoff; the aircraft dove into the Jakarta Sea on October 29, 2018 and all 189 passengers and crew aboard the aircraft were killed. The second crash was Ethiopian Airlines Flight 302. Similarly, the aircraft suffered 6 minutes of altitude change before crashing and killing all eight members of the crew and the remaining 149 passengers on March 10, 2019.

The first crash of the 737 MAX 8 prompted families of victims to point accusing fingers at Boeing and the aircraft itself. Accusations were thrown by various people at Lion Air itself and the maintenance of the aircraft. There was a faulty angle of attack sensor which should have been repaired prior to takeoff; a flight only a few days before had recovered from an MCAS anomaly, and this led some to accuse the pilots of insufficient training.

The MCAS

Between both of the claims by families is the common thread of the MCAS system. This program is the main culprit in causing the crashes, and the overwhelming concern about training for the MCAS system has led the entire world to ground the nearly 300 737 MAX-8’s currently in circulation.

The MCAS system is automated to prevent the aircraft from stalling. It uses the angle of attack (AOA) sensors (the angle of attack being the position of the airfoil in relation to the surrounding air) to automatically adjust the rear elevators of the aircraft through trim; this would push the nose of the aircraft down to prevent it from stalling. The program was designed to activate itself when the AOA is high, the autopilot is turned off, the flaps are mounted upward, and the aircraft is steeply turning. The problem with this system is that it depends on the angle of attack sensor which provided false information in both crashes.

Following the crash of Flight 610, multiple sources have come forward, revealing that the specific model which flew from Jakarta and then crashed in the Java Sea was not airworthy. The very same aircraft which would later crash in the Jakarta Sea actually recovered from a similar problem on October 28, 2018, a day before the fateful crash. Pilots of the Lion Air flight on October 28, from Bali to Jakarta, followed protocol and managed to remove all software that controlled by the anti-stalling MCAS software in the aircraft. They moved to a completely manual mode and performed a routine landing at Bali international airport.

Another Culprit: AOA

Technical problems with the aircraft had emerged with the MCAS system and more specifically, the airspeed indicator and AOA sensors. These indicators had malfunctioned on four previous flights. The AOA sensor allows for the MCAS system to adjust the angle at which the aircraft either ascended or descended. Continuous measurements of the angle of attack by the aircraft were false.

The software of the aircraft believed the aircraft was moving upward at a greater angle when in reality, the aircraft was not moving as far up. For this reason, the aircraft pushed the nose downward. In a battle to maintain a level course against the attempts of the aircraft to move downward, the pilots lost control of the aircraft. Between the actual crash and the takeoff, the pilots attempted to adjust the angle of attack nearly 20 times.

With the malfunction of the airspeed indicator, crucial adjustments in speed to control the 737 MAX 8 could have significantly affected the pilot’s decision making. Faster speeds on the airspeed indicator would mislead pilots in trying to escape possible stalls at a higher speed. Speeds of the aircraft were between 320 to 375 miles per hour; however, the skewed airspeed indicator and AOA sensor disrupted information the pilots received in the cockpit, possibly changing the decisions they made during the final stages of flight.

Fatal Similarities

The crews who are investigating both crashes have now found similarities between the angle of attack data from both aircrafts. Before the crash of Ethiopian Airlines Flight 302, some had blamed Lion Air for Flight 610; the company has the worst flight record in all of South Asia, with 11 crashes since 2000. While this does not prove that they were responsible for the deaths of all those aboard Flight 610, the Boeing 737 MAX 8 aircraft that flew along the route of Flight 610 was not certified as airworthy.

Despite Lion Air’s spotty maintenance standards and practices, Boeing is more to blame in this situation. As per a report by the New York Times, Boeing skimped on providing either aircraft with any form of an MCAS activation alert. The AOA sensor is not a standard feature, and hence the pilots could not have realized MCAS was the culprit for the aircraft’s erratic behavior. In more recent simulations, reenactments of Ethiopian Airlines Flight 302 suggests that pilots had about 40 seconds to recognize the activation of the MCAS. Pilots of both flights had 40 seconds to turn off a hidden feature they did not know existed–a deadly concoction of circumstances.

Information about Ethiopian Airlines Flight 302 is still limited yet the maintenance of the aircraft was not poor. In fact, a previous routine check had shown nothing wrong with the aircraft prior to takeoff and regardless of the maintenance, the AOA sensor still malfunctioned. The uncanny similarities between both crashes and the evidence from an investigation into the cause of the crashes have suggested that Boeing and the MCAS system were to blame.

Blaming Boeing

Newer information reported by the Wall Street Journal concerning the plane’s black box, an orange device which records flight data, has strengthened the claim that Ethiopian Airlines Flight 302 was downed by the MCAS system. Since these revelations, the U.S. government has begun an investigation into Boeing and the approval of the Boeing 737 MAX 8 by the Federal Aviation Administration (FAA). It is now believed that previous members of the Boeing company quickly approved the aircraft without meticulously examining the safety features of the airplane.

Prosecutors from the Justice Department of the United States have requested multiple members of both Boeing and the FAA to appear in court. The criminal investigation looks to uncover the true nature of the marketing strategies used by Boeing and the certification of the aircraft to begin commercial distribution. The prosecutors are also looking into the training requirements for the aircraft.

From the limited investigation of members of the aviation community, pilots were not very aware of the MCAS system. The feature seems to have been swept under the rug by Boeing to hide the flaw that its new, more environmentally friendly engines produced. Both Boeing and the FAA are not collaborating to provide a software fix for the 737 MAX 8. More information has been released as to the previous training programs for the new aircraft with one reports suggesting that it was not sufficient with a total of 2.5-hours on a course taken online.

Boeing has now developed a 30-minute informative course which should allow pilots to be better equipped for handling MCAS. At first, one of the major selling points of the new 737 MAX 8 was that it required no training on simulators for pilots to adjust to the airliner. Boeing still stands by this decision to limit the use of simulators. The process to clear the aircraft is ongoing and the aircraft remains grounded worldwide as of this writing.

The 737 MAX 8 is not a safe aircraft. While some may point to how mind-boggling the crashes themselves were, the approval and certification of the aircraft itself were even more puzzling. New software additions to the airplane will guarantee better safety, but until then, the 737 MAX 8 will have been one of the most dangerous planes to ever take flight. The reason: MCAS.

[Sources: forbes.com, cnn.com, nytimes.com, thedailybeast.com, cnn.com, theguardian.com, boeing.com, aircurrent.com, wsj.com]