WSJ claims that angle of attack sensors do not work on these airliners. It must be clarified that the angle of attack is the angle between the direction of movement of the aircraft and the direction of its nose. At the same time, as noted in the publication, Boeing became more “frank” with the operators of its aircraft only after the second crash, when, in March 2019, the airliner of Ethiopian Airlines crashed.
Only the numerous casualties and the massive abandonment of the operation of Boeing 737 MAX airliners around the world, prompted the corporation to worry about the existing problem.
By the way, the problem is that on the previous Boeing products, the same warning system works great, but in the new 737 MAX airliners it refuses to do this, for some unknown reason. But worst of all, it is generally unknown whether this system would have helped prevent disasters from occurring or not. Although the experts interviewed by the WSJ unanimously claim that the reasons for these two disasters are sensor malfunctions, signals from which did not reach the pilots or showed incorrect information.
It is necessary to remind that earlier WSJ already reported that the cause of two disasters could be a malfunction of the MCAS system (Maneuvering Characteristics Augmentation System). MCAS controls the rudders on the tail of the aircraft and is responsible for pitch (angular movement relative to the horizontal axis). This system is definitely needed by an airliner, because due to the peculiarities of the design, his nose bulges during the flight. At the same time, WSJ sources claimed that the pilots did not receive information from the MCAS.