wrote on 2/19/2019 12:59 PM:
On Tuesday, February 19, 2019 at 7:02:43 PM UTC, Eric Greenwell wrote:
wrote on 2/18/2019 9:58 PM:
I don't think disabling trailer brakes is a good idea. There is stability under heavy braking to consider not just retardation. I have twice, separated by about 25 years, had the situation of having to emergency brake on a motorway, the trailer start to swing out (not just sway) and then snap straight as the trailer brake bit fully. My impression was that if the trailer had been unbraked one or both times it would have jackknifed and possibly caused a multiple vehicle incident. Thankfully I will never know for sure but I would never tow a glider trailer any distance without good brakes..

With a 11,500 tow vehicle and 2500lb trailers, brakes are almost irrelevant for
stopping the combination - I did the experiment on an out and return to Alaska.
And now, the tow vehicle is 13,500lbs - it's even steadier.

Stability is not an issue with the huge difference in weight and the long wheel
base (with four tires on the rear) of the motorhome. Also, I tow 60 mph, pass at
70, and "flutter speed" is well over 100 mph. The trailer has so little affect on
the motorhome, I can't feel what it's doing, not even if a tire blows (done that
experiment).

The best argument for brakes in my situation is dampening the swaying if the
trailer came off the ball, but I believe the chains are strong enough to withstand
the whipping that would ensue, and the motorhome is heavy enough to be easily
controlled during the stop.


Eric I was quite specifically not referring to ordinary trailer swaying instability. I was referring to the driver having to make an emergency stop while towing and the trailer starting to try to overtake the vehicle. The weight of the towing vehicle would be no help there.

I misunderstood the situation you were describing. That's never happened to me,
even though I've had unbraked trailers from 4 different mfg over 17 years and 75+
thousands of miles around the North America, so I'm not concerned about it.

Also, I don't understand how the trailer could get very much out of line in my
situation: the more it yaws, the trailer tires will be directing back into line,
and the retarding force will be diminishing. The jackknifing I'm familiar with
involves very slippery pavement (ice or lots water - not the situation for 99% of
my towing), or the tow vehicle being pushed out of control (with 9,000 lbs on the
rear axle, it's not likely the 2500lb trailer can do that).

I still think your experience applies to people with lighter tow vehicles, and
they should cautious about disabling the brakes.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf