Reply to iano
Re Hydraulic disc brakes
Probably too late for you.
They’re very different in their auto reverse function to the civilian disk brakes used in the US and Australia/NZ, although it looks as if they should work with their civilian hydraulic tow hitches, subject to them pumping enough fluid.
The calipers are free to slightly rotate following the wheel rotation and in reverse this prevents the pads being effective.
The exact mechanics are set out in
Army Support Publication 2330-E-202-302
Made available on the web under an FOI request.
The system has the benefit of being entirely mechanical and not relying, as the civilian ones do, on an electric lockout solenoid cutting hydraulic flow when the reversing lights operate. The solenoid supposed to release when power is cut. Mine hadn’t when I later removed it to check my suspicions. And I’d been descending the Pyrenees.
Having fitted a U.K. road legal version of US Deemaxx discs to a boat trailer, I wish I’d seen this, as a suitable mechanical handbrake lever was surprisingly difficult to source.
