"Without corrective input, at a high angle of attack a 737 MAX will continue to pitch up further, leading to a stall. As a result, Boeing finds the 737 MAX design does not satisfy Federal Aviation Authority (FAA) airworthiness criteria for stability, particularly Federal Aviation Regulation (FAR) 25-173 [see appendix]. If the angle of attack of the aircraft exceeds 14 degrees, the nose will rise on its own until the aircraft stalls, unless a corrective action is taken."
Appendix: Federal Aviation Regulation Airworthiness Criteria Sec. 25.173 — Static longitudinal stability.
Under the conditions specified in §25.175, the characteristics of the elevator control forces (including friction) must be as follows:
(a) A pull must be required to obtain and maintain speeds below the specified trim speed, and a push must be required to obtain and maintain speeds above the specified trim speed. This must be shown at any speed that can be obtained except speeds higher than the landing gear or wing flap operating limit speeds or VFC/MFC, whichever is appropriate, or lower than the minimum speed for steady unstalled flight.
(b) The airspeed must return to within 10 percent of the original trim speed for the climb, approach, and landing conditions specified in §25.175 (a), (c), and (d), and must return to within 7.5 percent of the original trim speed for the cruising condition specified in §25.175(b), when the control force is slowly released from any speed within the range specified in paragraph (a) of this section.
(c) The average gradient of the stable slope of the stick force versus speed curve may not be less than 1 pound for each 6 knots.
(d) Within the free return speed range specified in paragraph (b) of this section, it is permissible for the airplane, without control forces, to stabilize on speeds above or below the desired trim speeds if exceptional attention on the part of the pilot is not required to return to and maintain the desired trim speed and altitude.
[Amendment 25–7, 30 FR 13117, Oct. 15, 1965]
I went to your link and there are a number of incorrect statements. I have never heard of Dennis Holeman, but he is not a pilot (nor am I) and is not in the aviation industry (again, nor am I). But he is wrong in quite a few of his statements.
The MCAS is not an anti-stall system. (Or at least that’s what Boeing claims.) It was designed to make flying the MAX “feel” like the NG so that training could be kept to a minimum.
You seem to believe the 737 MAX is an inherently unstable design. (Comparing it to an F-16 and F-117, and adding an article about the 767 running out of fuel and gliding to a runway, as if a 737 MAX is incapable of similarly gliding.) The 737 MAX has the same fuselage and wings of the 737 NG. Both planes are stable. Slightly larger engines mounted four inches forward on a plane that is 129 ft (or 143 ft) did not make it into an unstable fighter jet like an F-16. (Note that unstable aircraft have their center of gravity behind the center of lift, so moving engines forward a few inches did not likely move the CoG rearward.)
The MCAS was implemented to prevent the need for extra training, not to make an unstable aircraft stable. Where Boeing really screwed up was the fact that it relied on a single AoA sensor (despite having two installed on all 737s) and not having a way to disable the MCAS flight rules without disabling the entire electric trim system, and not accounting for the fact that the plane would be at such high speeds in a dive caused by a faulty MCAS that a human would be unable to move the manual trim wheel from the immense forces on the horizontal stabilizer. Very poor engineering to put it mildly.
The MCAS programming has subsequently been changed so that the maximum angle it can change the horizontal stabilizer is reduced, it will only initiate once instead of continuously, and will not activate if the two AoA sensors are in disagreement. Note that there was no change in the engine nacelles which create more lift than the ones on the NG during high AoA.