I'm not talking about white-knuckle trailer oscillations (I've been
there) but just some gentle swaying back and forth passing an 18
wheeler, etc. It was just something I elected to tinker with since the
trailer swaying subject seems to be a regular subject. But it might be
handy to know if something like this would work for the occasion where
things got a little hairy.

Eric Greenwell wrote:
Gary Emerson wrote:

This is different, but related to your subject. I found that if I was
looking in the rear view mirror at the tail of the glider trailer that
I could actively damp out trailer sway by gentle steering inputs that
were opposite the perceived tail direction in the rear view.

If, looking at the image in the rear view, the tail was going left to
right, then I applied a left steering input and vice versa. This
seemed to help quite a bit when the occasional gust would get things
moving. Experiment with care...it was very tempting initially to steer
"with" the tail and took some focus to time the inputs in the opposite
direction.


If an "occasional gust would get things moving", I think you are driving
too fast. Oscillations that last long enough to damp out the way you
describe indicate you are close, maybe very close, to diverging
oscillations. It might take only a larger gust (or a couple in row),
tires that are a few pounds low (trailer or tow vehicle), or a sharp
avoidance maneuver, and suddenly you are a passenger.