Pete Schaefer wrote:

Rule #1 of Flight Controls Design: KNOW YOUR PHYSICS! At the end of the day,
F still equals ma, and you ain't getting past that doing any fuzzy stuff.


Pete, thank you for your concern, and I don't mind the flaming. Really 8*)

But it is obvious that you have spent years in the industry designing
flight systems for large aircraft. I applaud that and hope to learn a
thing or two. But let me throw a rule out:

Rule #1 of Homebuilt Flight Controls Design: DON'T EVER GIVE ANYTHING
ELECTRONIC CONTROL! At the end of the day, if you can't overpower the
the electronic gizmo with moderate effort then leave it on the ground.

I've had this discussion before. I'm building and airplane for
ENJOYMENT. Getting beat to death in the soup is not my idea of a good
time, so I would not bother with a system that has enough power to
control things in choppy weather. I'm currently designing a cooling
system for my rotary auto conversion, and I'm not designing it for
sustained operations at 100F, because sitting under a plexiglass
slowcooker of a canopy is also not my idea of a good time.

Smooth flight in a light plane is predicated on a lot of small inputs
made early. The earlier it's made, the smaller it has to be. A long
series of continuous nudges. Stepper motor would be fine. You tie it
into the system through a couple of springs, and if you're asking for
more force than what they deliver then you've already gone off the wrong
side of the page. If it goes belly up, then it is an irritation, but no
more so than the CFI who won't get his $&*$ feet off the rudder pedals.
You can't tell it to move it's feet, but you can shut it down and then
nullify it's input with trim. (That's right. Trusty mechanical trim
stays right where it's at. Maybe beefed up just a tad, since it may be
given new duties.) In any case, there is no point where the pilot is
free to let go of the yoke.

Do not even bring up the subject of 'fly-by-wire'. I'm a software
engineer, and there is no way I'd trust a computer with my butt unless
it was built and maintained by a properly trained team (which I am not)
and had multiple backups (which I couldn't fit in my little plane). I
don't even think that most GA aircraft should fly IFR, especially those
depending on electronics. Very few people have the budget to buy the
type of equipment that is really necessary for blind operations (the
sort of equipment that I suspect you helped design), fewer can afford a
plane big enough to carry it all, and even fewer can afford to maintain
it properly.