This article doesn't get the point right. From this article it sounds like some optional "helper" system for pilots to avoid stall. Another article got it right, the plane itself is unstable because of big engines if the MCAS is not there to stabilize it. So its not some optional system, that the pilots would switch off when manually controlling the plane, its there for the plane to fly at all.
> So its not some optional system, that the pilots would switch off when manually controlling the plane, its there for the plane to fly at all.
And that fact makes it utterly damning that there is absolutely no redundancy. A single sensor?
It's a critical component. No redundancy on a system that can control flight.
There's no instability whatsoever in level flight, at least relative to other planes. The issue is that the large surface area of the engine nacelles is far forward of the plane's CoM. The effect of this is that the control stick becomes 'lighter' as you approach high AoA. This is considered acceptable - though not ideal - in many aircraft, but would have changed the pilot rating requirements from the old 737s.
Some people seem to be suggesting that this is some sort of advanced stability system; the reality is that this is just an automated trim adjustment. Clearly it's very important, but the idea that the plane couldn't fly at all without it is absurd.
No redundancy on a system that can control flight. A system that is supposed to help avoid a stall scenario.
That alone is a crazy oversight, let alone differences between safety analysis and actual capabilities.
This stinks of truly awful management - the rules of the sky were written in boood. Ignoring them has shown serious consequences, because we already knew not to do this.