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The last time a new model aircraft suffered successive fatal incidents like the 737MAX8 series has recently was back in the 1970s with McDonnell Douglas' DC 10s. Following the grounding of the aircraft by the European Union and other states,here's what they're not telling you; 
Boeing wanted to update their 737 to a more fuel efficient aircraft (the 737max8)but they also didn't want to modify the plane's flight systems to the point of requiring retraining the 737 pilots to take over the new 737max8, a process that would be expensive...
So in reinventing the aircraft, bigger and heavier engines were required to be fitted for better fuel consumption. Being heavier, the engines couldn't be fitted in the exact same place they were in on the 737 if the aerodynamic centre of gravity was to be maintained
So the engines had to be moved up higher and more forward on the wings to achieve this. But this change and the fact that they were heavy also caused in-flight hazards such as stalls that the plane would suffer beyond a particular angle of lift and at low speeds
So, to avoid this issue of stalling, Boeing, contrary to their original plans of maintaining the 737max as exactly the same aircraft as the 737 in terms of flight control, had to introduce software to counteract situations when the plane would be in a condition of stalling
(A stall is a situation in flight when a plane loses lift over it's wings after exceeding a certain nose up angle and begins to drop to the ground like a hot potato)This software is termed as MCAS (Manuevering Characteristics Augmentation System)The way this works is as follows
The plane was fitted with Angle of Attack (AOA) sensors on both sides of the fuselage close to the cockpit, sensors who's job is to keep track of the angle of the nose of the aircraft. If the nose of the aircraft moved higher than an angle the engineers of Boeing determined...
...would cause the aircraft to stall due to its heavy engines, these sensors would then send signals to the plane's system to trigger the MCAS to prevent the stall. What the MCAS would do is; it would automatically access the plane's horizontal stabilisers on the plane's tail...
...through the flight control computer and angle them to bring the nose back down from those dangerous angles. This was the only system update according to Boeing that they made to the max8 (apparently)
On commissioning of the aircraft, Boeing argued that this was a change so small that it was not necessary for the pilots from the 737 taking over the max to know about as it was an automatic system meant to improve handling of the plane in abnormal conditions
So, the FAA agreed and the pilots were kept in the dark about this system update at first and continued flying the max8 the same way they did the 737. Then the Lion Air crash occurred. From the plane's flight data recorder, the plane demonstrated a nose down movement...
...triggered by the MCAS during normal flight just after take off from Jakarta, Indonesia. They said that erroneous data was fed to the system from a faulty AOA (the AOAs feed data to the system independently).
Now in the 737 before the max, pilots could regain control of the aircraft from automatic flight by pulling back on the yoke (the flying stick in front of the pilots) but this was a feature that was removed from the system in the updated max8, and so...
...the only way of regaining manual control over the MCAS would be to turn it off over the flight control panel, switching off the MCAS and manually setting the stabilisers. But the pilots wouldn't know of this if they weren't told about the MCAS in the 1st place
Pilots of the Ethiopian Airline allegedly had difficulty of the same nose down pattern before the crash. It was after the Lion Air crash that pilots were now made aware of the new software in the max8. But even before, pilots from around the globe had made complaints of...
...a nose down behavior in the max8 during normal flight. Given the similarity in characteristics of both incidents of the max8 crashes so far, one would argue that both planes faced the same problem! But the FAA and Boeing continue to argue that the plane is safe to fly.
Despite the grounding of the plane by the European Union, China, Australia, and other major parts of the world except the US, the FAA hasn't officially moved to ground the aircraft, saying it has no grounds to do so as of now during on going investigatons into Ethiopia's crash
Worthy to note is that the CEO of Boeing, a company that donated 1million dollars to Trump's inauguration, gave Trump a call in which it is said he requested Trump not to ground the plane in the United States. Also, the max8 series alone...
...provides Boeing with a third of its commercial profits as of today, but the grounding of the plane is giving Boeing's stock a beating. Question is, is the new software in the max8 that is meant to keep the plane safe actually doing the opposite?
