Feel System force levels
Note: On realization of a significant oversight in my thoughts, I have revised my post below.
One of the stabilator equipped jets I used to fly started life with a rather steep stick force gradient in pitch. Pilots were objecting to the force gradient and the Navy requested that the gradient be decreased.
I had opportunity to fly both versions in extreme maneuvering flight. The version with the steep gradient left me with strained muscles in my stick handling arm. The version with the lighter gradient could be flown with fingertips in extreme maneuvering flight.
The transition between the two types was negligible. In event of complete failure of the aircraft feel system (blockage of the feel system pitot) you could overpower the system with comfortable force levels, but you could control the aircraft.
Perhaps the 737 would benefit from lower force gradients in pitch control as well, although if you run out of elevator authority due to THS position, you will still begin to lose control.
If the feel force levels never reached astronomical levels, it would then be easier to reach the limits of the elevator input command travel. Should you reach perhaps 95% of travel, that could be used as a signal to override the THS position commanded by MCAS and reduce any MCAS commanded trim.
Remember, you are not feeling aerodynamic forces through the stick. You are merely wrestling with a hydraulic powered device in the back of the aircraft. The force levels can be adjusted by changing the hydraulic pressure applied.
Arguments against reducing the force gradient probably center on preventing inadvertent over-G events and on maintaining feel commonality with earlier Boeing transports. I suspect that these arguments will be found to be overstated if actual flight testing of a reduced stick force gradient is performed.
Last edited by Machinbird; 17th Mar 2019 at 06:47.