Originally Posted by
tdracer
Those numbers are for "Sea Level Static" thrust. Thrust in-flight is different. On large turbofan engines, the net thrust 'lapses' (decreases) with forward speed - the higher the bypass ratio, the greater the lapse with speed (very basically, the ram drag on the inlet goes up faster than the gross thrust generated by the fan exhaust).
I don't have any specific information for the MAX, but I suspect you'd find that, because of the much higher bypass ratio on the Leap, at ~250 knots, the net thrust of the NG -800 and MAX -8 are much closer than the SLS thrust.
The MCAS system was not designed for 250 kts, it was designed for low speed upsets near the stall. And those events normally (but not exclusively) take place near to sea level. So Boeing would certainly have had to take into account the pitching moments caused by those thrust levels. And the Max does indeed have much more thrust than the old -400. And the NG’s thrust can indeed overpower the elevator, as has already been demonstrated (with passengers aboeard).
Although it would be interesting to see if anyone tried out an inadvertant MCAS operation at 300 kts at 10,000 ft, to see what would happen.
Silver.