[mcv]

Yeah, the stories about how the new requirements didn't fit the limitations of the 737 design, and how they had to make it unbalanced and correct that inherent instability in software, throws up a bunch of red flags. At some point, you need to accept that the original design doesn't work anymore for the current requirements and redesign the whole thing from scratch. Or at least more thoroughly than the quick & dirty fix they used here.

[jaywalk]

The 737 MAX does not have "inherent instability."

The position of the engines causes the plane to pitch up more significantly when power is added. This is not necessarily bad, but it's different enough from the 737 NG that it would have required retraining pilots. MCAS was designed to remove the need for retraining, by using software to make the MAX act like the NG.

If everyone would have simply accepted that pilots needed to be retrained for the 737 MAX, MCAS wouldn't have been developed and those planes wouldn't have crashed.

[sokoloff]

You’re right in the first point, but wrong on the second and then maybe right again on the third. There’s a specific federal law concerning the pitch force curve stability (https://www.law.cornell.edu/cfr/text/14/25.173) that the Max violated, meaning it was not going to be able to be certified as a 737 or as a new, clean sheet airplane, with the demonstrated stick force curve.

Now, if you’re going to make a clean sheet design and allow a new type rating, you can change the landing gear and wing design to achieve enough room to set the engines farther back and change the airfoil around them to design a plane that meets 25.173. Boeing already has such a plane: the 757.