Here is the first in a series of topics that I’ll try to do regularly and sometimes in French or sometimes in English. This subject is in fact the first topic that I’ve done this year in my Aerospace Engineering school during the English lessons. A topic is a little presentation of a subject, and often it is necessary to present a product and its controversial effects. It’s what I’m going to do.

So first some important dates : 

– 2011 : Conception 

– 2016 : First test flight

– 2017 : First commercial flight

– 2018 : First accident (Lyon air)

– 2019 : Second accident due to some problems (Ethiopian Airlines)

There are 4 versions of the B737 MAX : MAX 7/8/9/10

Why a new airplane ?

The competition was present and the time for an advanced aircraft had come: an aircraft that consumes less (15% less) but also safer with new structures such as winglets with more efficient and therefore larger engines.

But being bigger, the engines are therefore higher and the weight and balance calculations change. As a result, the stall speed increases, leading the design team to create a new system. This new system is MCAS.

MCAS works using a probe calculating the aircraft’s angle of attack. If the angle is too large, the system acts directly on the elevator in order to stabilize the aircraft by making it nose down to prevent stalling. The plane is therefore named as 

‘ The safest plane in the world ’

For its part, Airbus is developing the A320 neo, affiliating the same engine but under its first version. 

The safest plane in the world, two accidents

There are two accidents of the B737 Max, two tragedies. The first for Lion Air in October 2018 and the second for Ethiopian airlines in March 2019. The two crashes resulted in 146 deaths.

How to explain these crashes?

MCAS links the information sent by the sensors. But in this case, it is actually only a single sensor of the two calculating the aircraft’s angle of attack ans send informations to the MCAS. When this sensor is faulty, the MCAS no longer receives acceptable data. This is a problem because the software reacts according to the data sent. When the software detects an angle of attack that is too large, it will nose down the aircraft to stabilize it. So that’s how the accidents happened, with wrong angle data and a constantly with a nose-down angle.

The pilots were trying to regain control of me could not long. A button cutting the elevator trim could be used.

However, the pilots applied the checklists perfectly, and this button was not there. They did not have the reflex or the time to cut it.This is why there is a problem with training and design as well as the transmission of procedures, ie a lack of clarity.

Airplanes situation 

Similarities between both crashes have forced aviation regulations to ground every 737 MAX allowing a loss of over $18 billion. It was also decided that the FAA have to approved each plane before a come back to the compagnies. Moreover, aviation regulations from Europe, China or Brazil have their own requirements to allow planes to fly again.

Boeing’s difficulties

For this reason, Boeing has released a new version of the MCAS system which asks new pilot formations. And these trainings concern more than 10.000 pilots and there are only 2 B737 MAX simulators. That’s why international requirements are expansive and very heavy for Boeing.

The nefarious reputation

The reputation of Boeing has been roughly tarnished. A bank of America survey among travelers revealed that 60% of them would wait at least 6 months before flight again with a B737 MAX and only 20% will feel safe. Moreover, some compagnies like Quantas, Air France or United Airlines have recently chosen Airbus. For instance, the B777 is already losing orders.

Fly again soon ? 

A recent press release tells us that the 737 Max are on the last certification path and could fly by early 2021. Important tests are underway granted the conditions.

Boeing’s economy may recover, but the risk of a major crisis, particularly with COVID, makes the task complicated. In my opinion, it is possible that Boeing is having difficulty getting up. With fewer passengers, the 737 MAX crisis and the coronavirus, the company may not recover. However, powerful companies often come out of these situations.

This raises several questions:

Confidence in advanced technologies and in autonomous devices. But also to the power of companies and the unfortunate fact that accidents allow progress. It is therefore also an ethical problem.

Between economy, dramas, crises and technology, will Boeing be able to recover?

The Boeing 737 MAX

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