An old & retired 100-hr 'bus driver here. Was tipped off the type (with pleasure) from the 2nd intake of the second '320 new to the second airline to use them, and was horrified at the control interface & design assumptions. On the other hand the Porsche designed cockpit layout and side-stick made it a dream machine to ride around in, and the things are built like Swiss watches.
For my previous airline & other legs I always hand-flew aircraft to TOC, accelerated, trimmed and cruise inserted before plugging george in. This habit keeps you tightly in the loop re mach effects as you transition from asi to mach, while manually or electrically trimming so you are only ever controlling with your fingertips, locking in zeroing-out elevator loads out constantly. Nothing is then under stress.
Reverting to type on the 'bus I quickly found it a useless occupation. You are basically flying in permanent control wheel steering. You point it to up and it goes up. But doesn’t stay like that.
I found that if you took hand off in CWS, the pitch would very slowly increase, at approx 1° in 12-15 seconds. Autothrottle would mask speed loss. You are playing a computer game in 'buses. I established that it took a fwd pressure with one finger at the top of the side stick (which I lurved) of 8-10 grams, from a spring balance at home with skin deflection comparisons.
So if an autopilot dropped off-line unannouced (of *course it couldn'd happen, could it, coff) the aircraft would slowly begin a long upward arc.
I twice wrote to Airbus, attn. flight testing, at Toulouse, first time as a query, second time more tersely, but was never answered
AFAIK. The airline dispute of '89 interupted my hours on type, and I was very happy to revert to actually controlling other birds again, elsewhere.
So in (a long) answer to your Q, Gums. It uses springs, and to make it worse of course, there is zero interconnection between sticks. There is a dinky little dial down there somewhere that shows you who’s doing what with which side-stick. I’m told.
If they had just run some model aeroplane wire-in-tube across the top of the cockpit between the sticks, so that the p’lots could feel what’s going on, those hundreds of people flying across the Western Atlantic in a ‘bus would still be alive.
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One slightly off topic question: does anyone know why aeronautical engineers went off flying-tabs, a.k.a. servo-tabs. I flew them on the Vickers Viscounts 700, 800 & 900, and they are soo logical. (What’s that? What’s a Viscount 900 then? Well Vickers went bust, and a raft of their designers were grabbed by Douglas, then designing the DC-9. Servo tabs came with those blokes, & they knew their stuff.) Those type of tabs mean that airspeed-induced control-loads are dealt with by well designed servo-tabs sitting in that same airflow. Fabulous control feel & feedback. Light and progressive stick loads, light gauge & light-weight control runs, and all self powered to boot. Lose every service and you don’t have to *think of unpowered controls problems. (I’m looking at your flying hefferlumps, Mr Boeing.)
Any ideas why they’re no longer designed in?