Originally Posted by
gums
Salute!
...That being said, there is one big thing I like about getting as much hand-flying time whenever you can. It is the "feeling" when the plane does something that you do not expect considering either the Otto mode or your own control inputs or trim settings. You know........., you did this hundreds of times but this time is "different". When letting Otto do the climbout/letdown and such, you should be mentally flying the same profile and be able to see where your manual inputs would be in effect or where Otto did something completely off the wall...
Now back to your regular programming...
Gums...
interesting.
Dear defanged viper, IIRC, your ride, Boyd's mafia LWF, had an FBW FLCS (analog in 79..., digital later). Stevens and Lewis provide the control derivatives in Appendix A of their book on the wonders of control and simulation. In pitch, y'all had RSS, so essentially response there is from one of the 4 PFM boxes so long as the smoke remains inside the boxes. The original YF prototype IIRC had an immovable SSC, just being a handle for force sensors to be attached to. By the time it hit production, you had slight motion of the stick, but no feedback. Your Viper had a trim switch on the SSC which trimmed out lateral asymmetry and in pitch varied the force free manoeuvre g, IIRC, not having had the pleasure of much beyond a rear seat fly of an early block electrojet... Was the feeling you got actually derived from the FLCS or the need to apply say a constant force for at least the lateral input for a stores asymmetry or similar? In later blocks, with the digital computers things were broadly the same but the relaxation of stability could be taken further, and fun effects could be played with. On commercial aircraft, (le Concorde was an analog FBW aircraft too) such as the 777 787 and the 320-330-340-350-380, there are differences between brands. The Boeing is slightly weird by design choice, it does force feedback, and the driver is given trim input which indexes the trim speed. To an extent it gives a nearly conventional feedback, but with stability in roll mainly, and oddly a phugoid just to bedevil the curious. The 'buses have no feedback, they really are nintendo devices, but they do have a nice manoeuvre demand logic. The natural control feel of a FBW system is about the same as the control panel of a microwave oven for the SSC systems. If the designer wants to give feedback, that is an artificial feel, fed back by servos to a moveable control, like a 787, or F18 etc, and that feel can be whatever they decided was a good thing at the time, from the microwave oven control panel through to the Wright Flyer. Feeding back oddities and funnies into the controls is a function on what derivatives the designer wants the driver to deal with. They can wash out all anomalies, so the plane doesn't tell that the left wing was taken off, a flap failed to run, etc... whatever floats their boat.
The copy I have of 16DFCS003 is a lousy report version from DTIC, but it doesn't show much going back to the driver in feedback other than the aircraft performance outcome. As is usually the case, looking at the gains tells a great story of the planes character though.
just curious.