Tow vehicle -- electronic stability control

[Greg Arnold]

My understanding is that electronic stability control is a device that
selectively applies individual brakes in an attempt to prevent oversteer
and understeer. Does anyone know whether this reduces the swaying of a
tow vehicle, or maybe even increases swaying if the device reacts too
slowly?

[Gary Emerson]

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.

Greg Arnold wrote:
> My understanding is that electronic stability control is a device that
> selectively applies individual brakes in an attempt to prevent oversteer
> and understeer. Does anyone know whether this reduces the swaying of a
> tow vehicle, or maybe even increases swaying if the device reacts too
> slowly?

[Capt. Geoffrey Thorpe]

"Greg Arnold" > wrote in message
news:8Rhhg.11367$KB.7672@fed1read08...
> My understanding is that electronic stability control is a device that
> selectively applies individual brakes in an attempt to prevent oversteer
> and understeer. Does anyone know whether this reduces the swaying of a
> tow vehicle, or maybe even increases swaying if the device reacts too
> slowly?

I don't mean to sound like a smartass (for a change), but what does the
owners manual say?

If the stability control is going to cause problems when towing a trailer,
it makes sense that the manual would suggest turning it off, eh?

I did find a manual that suggested that you turn off the stability control
when you have chains on the tires, but nothing about trailer towing.

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Eric Greenwell]

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.

--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"

[Gary Emerson]

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.
>