Comment 737 Max 8 has deep aerodynamic flaws (Score 1) 413
This article with commenting from a pilot with 30 years of flying experience and 40 years of developer experience gives the clearest explanation I've found about the flaws of the 737 Max 8. From the article:
The solution was to extend the engine up and well in front of the wing. However, doing so also meant that the centerline of the engine’s thrust changed. Now, when the pilots applied power to the engine, the aircraft would have a significant propensity to “pitch up,” or raise its nose. This propensity to pitch up with power application thereby increased the risk that the airplane could stall when the pilots “punched it”
Worse still, because the engine nacelles were so far in front of the wing and so large, a power increase will cause them to actually produce lift, particularly at high angles of attack. So the nacelles make a bad problem worse.
I’ll say it again: In the 737 Max, the engine nacelles themselves can, at high angles of attack, work as a wing and produce lift. And the lift they produce is well ahead of the wing’s center of lift, meaning the nacelles will cause the 737 Max at a high angle of attack to go to a higher angle of attack. This is aerodynamic malpractice of the worst kind.
It violated that most ancient of aviation canons and probably violated the certification criteria of the U.S. Federal Aviation Administration. But instead of going back to the drawing board and getting the airframe hardware right, Boeing relied on something called the “Maneuvering Characteristics Augmentation System,” or MCAS.
