Center of gravity and control effectiveness
Salute!
Well, Harry, I joined the forums soon as I could when the plane was lost. Long time FBW pilot, and I was "interested".
The planes with the relaxed static stability can easily tread where no other planes and pilots have dared to tread.
I have a problem with "certification" of such a beast unless I am assured that there are mechanisms to keep the c.g. within the capabilities of the basic aerodynamics that may be encountered and the available pilot/crew inputs when things turn to worms.
The jet I flew only had one such fall back mechanism, and we couldn't even use the switch unless our AoA was far beyond the normal limits of the flight control computers.
Flying about with an aft c.g. that previous designs could not handle without a FBW system is inherently risky. I fully realize that mission determined my jet's control laws, as it did for the Airbus. OTOH, there comes a point where the pilot/crew must use the system in a way that is not allowed for when things go beyond the design spec. As I said, I am against manual override except for one or two conditions where the computers get bad data or the plane is in a condition not envisioned for "normal" flight control laws.
I would not rule out an out of limit aft c.g. as a contributing factor. Hell, the "normal" aft c.g. scares me.
I would like to see the pitch moment graph that I put out for the Viper compared to that of the Airbus. Anybody here has such a graph?
respectfully,
Gums sends...